67 results on '"Jackson G. Egen"'
Search Results
2. Therapeutically targeting type I interferon directly to XCR1+ dendritic cells reveals the role of cDC1s in anti-drug antibodies
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Paul Noe, Joy H. Wang, Kyu Chung, Zhiyong Cheng, Jessica J. Field, Xiaomeng Shen, Stephanie C. Casey, Christa L. Cortesio, Cinthia V. Pastuskovas, Hyewon Phee, Kristin V. Tarbell, Jackson G. Egen, and Amy-Jo Casbon
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immunogenicity ,interferon ,immunotherapy ,dendritic cells ,conventional type I DCs ,antibody IFN fusion ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Conventional type 1 dendritic cells (cDC1s) are superior in antigen cross-presentation and priming CD8+ T cell anti-tumor immunity and thus, are a target of high interest for cancer immunotherapy. Type I interferon (IFN) is a potent inducer of antigen cross-presentation, but, unfortunately, shows only modest results in the clinic given the short half-life and high toxicity of current type I IFN therapies, which limit IFN exposure in the tumor. CD8+ T cell immunity is dependent on IFN signaling in cDC1s and preclinical studies suggest targeting IFN directly to cDC1s may be sufficient to drive anti-tumor immunity. Here, we engineered an anti-XCR1 antibody (Ab) and IFN mutein (IFNmut) fusion protein (XCR1Ab-IFNmut) to determine whether systemic delivery could drive selective and sustained type I IFN signaling in cDC1s leading to anti-tumor activity and, in parallel, reduced systemic toxicity. We found that the XCR1Ab-IFNmut fusion specifically enhanced cDC1 activation in the tumor and spleen compared to an untargeted control IFN. However, multiple treatments with the XCR1Ab-IFNmut fusion resulted in robust anti-drug antibodies (ADA) and loss of drug exposure. Using other cDC1-targeting Ab-IFNmut fusions, we found that localizing IFN directly to cDC1s activates their ability to promote ADA responses, regardless of the cDC1 targeting antigen. The development of ADA remains a major hurdle in immunotherapy drug development and the cellular and molecular mechanisms governing the development of ADA responses in humans is not well understood. Our results reveal a role of cDC1s in ADA generation and highlight the potential ADA challenges with targeting immunostimulatory agents to this cellular compartment.
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- 2023
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3. Brief report: STING expressed in tumor and non-tumor compartments has distinct roles in regulating anti-tumor immunity
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Jennie C. Kim, Xian Liu, Karen Fitzgerald, Jason S. Eng, Jessica Orf, Sarah A. O’Brien, Brian Belmontes, Amy-Jo Casbon, Sergey V. Novitskiy, Kristin V. Tarbell, Jason DeVoss, and Jackson G. Egen
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Cancer Research ,Oncology ,Immunology ,Immunology and Allergy - Abstract
Type I interferon-mediated activation of immune cells can facilitate the generation of productive tumor antigen-specific T cell responses in solid tumors. The cGAS/STING DNA sensing pathway is a critical upstream mediator of type I interferon production and is an important regulator of anti-tumor immunity. Numerous STING pathway agonists are now being tested in clinical trials, but the effectiveness of this approach is not yet clear and a better understanding of the relative importance of this pathway in various tumor settings is needed. We have evaluated syngeneic tumor models with different baseline inflammatory states to determine the contributions of STING activity in both tumor and non-tumor cellular compartments to anti-tumor immune responses. We find that productive anti-tumor immune responses in the poorly immunogenic B16F10 model show a strong dependence on STING expression in non-tumor cells. In the immunogenic MC38 model, constitutive STING activation in tumor cells can partially bypass the requirement for STING-dependent activity from immune cells. Our findings reveal multiple, context-dependent roles for STING activity in the regulation of anti-tumor immunity and the response to immunotherapy. In preclinical models where STING is basally active, checkpoint inhibition is more likely to have a therapeutic effect and removal of STING signaling from either the tumor or the non-tumor compartment has a minimal effect. Removal of STING signaling in both, however, diminishes the efficacy derived from checkpoint therapy. Further work is needed to understand the heterogeneity of STING signaling in patients, both in tumor cells and the tumor microenvironment, and the best means of harnessing this pathway to generate anti-tumor immunity and improve therapeutic outcomes.
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- 2022
4. Targeting Solid Tumors with Bispecific T Cell Engager Immune Therapy
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Tara Arvedson, Julie M. Bailis, Carolyn D. Britten, Matthias Klinger, Dirk Nagorsen, Angela Coxon, Jackson G. Egen, and Flavius Martin
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Cancer Research ,Oncology ,Cell Biology - Abstract
T cell engagers (TCEs) are targeted immunotherapies that have emerged as a promising treatment to redirect effector T cells for tumor cell killing. The strong therapeutic value of TCEs, established by the approval of blinatumomab for the treatment of B cell precursor acute lymphoblastic leukemia, has expanded to include other hematologic malignancies, as well as some solid tumors. Successful clinical development of TCEs in solid tumors has proven challenging, as it requires additional considerations such as the selectivity of target expression, tumor accessibility, and the impact of the immunosuppressive tumor microenvironment. In this review, we provide a brief history of blinatumomab, summarize learnings from TCEs in hematologic malignancies, and highlight results from recent TCE trials in solid tumors. Additionally, we examine approaches to improve the efficacy and safety of TCEs in solid tumors, including therapeutic combinations to increase the depth and durability of response.
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- 2022
5. Human Anti-tumor Immunity: Insights from Immunotherapy Clinical Trials
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Lawren C. Wu, Jackson G. Egen, and Wenjun Ouyang
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0301 basic medicine ,Cell type ,T-Lymphocytes ,medicine.medical_treatment ,Programmed Cell Death 1 Receptor ,Immunology ,Lymphocyte Activation ,B7-H1 Antigen ,03 medical and health sciences ,0302 clinical medicine ,Immunity ,Neoplasms ,Tumor Microenvironment ,medicine ,Humans ,Immunology and Allergy ,CTLA-4 Antigen ,Tumor microenvironment ,biology ,Antitumor immunity ,Antibodies, Monoclonal ,Cancer ,Immunotherapy ,medicine.disease ,Clinical trial ,030104 developmental biology ,Infectious Diseases ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,Antibody - Abstract
Therapeutics that target the T cell inhibitory checkpoint proteins CTLA-4 and PD(L)1 are efficacious across a broad range of cancers, resulting in reductions in tumor burden and increased long-term survival in subsets of patients. The significant and wide-ranging effects of these immunotherapies have prompted the clinical investigation of additional therapies that modulate anti-tumor immunity through effects on T cells, myeloid cells, and other cell types within the tumor microenvironment. The clinical activity of these newer investigational therapies has been mixed, with some therapeutics showing promise but others not exhibiting appreciable efficacy. In this review, we summarize the results of select recent clinical studies of cancer immunotherapies beyond anti-CTLA-4 and anti-PD(L)1 and discuss how these results are providing new insights into the regulation of human anti-tumor immunity.
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- 2020
6. Immunotherapy combinations overcome resistance to bispecific T cell engager treatment in T cell–cold solid tumors
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Brian Belmontes, Rajkumar Noubade, Sarah A. O’Brien, Hayley Ma, Jason DeVoss, Benjamin M. Alba, Hong Tan, Jason Eng, Melissa Thomas, Kevin Cook, Deepali V. Sawant, Peng Li, Matthew Chun, Jackson G. Egen, Wendy Zhong, Anupurna Kaul, Famke Aeffner, Olivier Nolan-Stevaux, Xiaoting Wang, and Markus Muenz
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CD3 Complex ,T cell ,medicine.medical_treatment ,Antigens, CD19 ,CD8-Positive T-Lymphocytes ,CD19 ,Mice ,Antigen ,Neoplasms ,Antibodies, Bispecific ,parasitic diseases ,medicine ,Animals ,Humans ,biology ,business.industry ,General Medicine ,Immunotherapy ,Immune checkpoint ,Blockade ,medicine.anatomical_structure ,Claudins ,Cancer cell ,Cancer research ,biology.protein ,business ,CD8 - Abstract
Therapeutic approaches are needed to promote T cell-mediated destruction of poorly immunogenic, "cold" tumors typically associated with minimal response to immune checkpoint blockade (ICB) therapy. Bispecific T cell engager (BiTE) molecules induce redirected lysis of cancer cells by polyclonal T cells and have demonstrated promising clinical activity against solid tumors in some patients. However, little is understood about the key factors that govern clinical responses to these therapies. Using an immunocompetent mouse model expressing a humanized CD3e chain (huCD3e mice) and BiTE molecules directed against mouse CD19, mouse CLDN18.2, or human EPCAM antigens, we investigated the pharmacokinetic and pharmacodynamic parameters and immune correlates associated with BiTE efficacy across multiple syngeneic solid-tumor models. These studies demonstrated that pretreatment tumor-associated T cell density is a critical determinant of response to BiTE therapy, identified CD8+ T cells as important targets and mediators of BiTE activity, and revealed an antagonistic role for CD4+ T cells in BiTE efficacy. We also identified therapeutic combinations, including ICB and 4-1BB agonism, that synergized with BiTE treatment in poorly T cell-infiltrated, immunotherapy-refractory tumors. In these models, BiTE efficacy was dependent on local expansion of tumor-associated CD8+ T cells, rather than their recruitment from circulation. Our findings highlight the relative contributions of baseline T cell infiltration, local T cell proliferation, and peripheral T cell trafficking for BiTE molecule-mediated efficacy, identify combination strategies capable of overcoming resistance to BiTE therapy, and have clinical relevance for the development of BiTE and other T cell engager therapies.
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- 2021
7. LILRB1 Blockade Enhances Bispecific T Cell Engager Antibody–Induced Tumor Cell Killing by Effector CD8+ T Cells
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Wenjun Ouyang, Andrew K. Sewell, Aeryon Kim, Xin Yu, Ian Driver, Jackson G. Egen, Zemin Zhang, Chia-Jung Han, and Aleksandra Olow
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Tumor Immunology ,Chemistry ,Effector ,T cell ,medicine.medical_treatment ,Immunology ,Immunotherapy ,Immune checkpoint ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Antigen ,medicine ,Cancer research ,Immunology and Allergy ,Cytotoxic T cell ,Receptor ,CD8 ,030215 immunology - Abstract
Elicitation of tumor cell killing by CD8+ T cells is an effective therapeutic approach for cancer. In addition to using immune checkpoint blockade to reinvigorate existing but unresponsive tumor-specific T cells, alternative therapeutic approaches have been developed, including stimulation of polyclonal T cell cytolytic activity against tumors using bispecific T cell engager (BiTE) molecules that simultaneously engage the TCR complex and a tumor-associated Ag. BiTE molecules are efficacious against hematologic tumors and are currently being explored as an immunotherapy for solid tumors. To understand mechanisms regulating BiTE molecule–mediated CD8+ T cell activity against solid tumors, we sought to define human CD8+ T cell populations that efficiently respond to BiTE molecule stimulation and identify factors regulating their cytolytic activity. We find that human CD45RA+CCR7− CD8+ T cells are highly responsive to BiTE molecule stimulation, are enriched in genes associated with cytolytic effector function, and express multiple unique inhibitory receptors, including leukocyte Ig-like receptor B1 (LILRB1). LILRB1 and programmed cell death protein 1 (PD1) were found to be expressed by distinct CD8+ T cell populations, suggesting different roles in regulating the antitumor response. Engaging LILRB1 with its ligand HLA-G on tumor cells significantly inhibited BiTE molecule–induced CD8+ T cell activation. Blockades of LILRB1 and PD1 induced greater CD8+ T cell activation than either treatment alone. Together, our data suggest that LILRB1 functions as a negative regulator of human CD8+ effector T cells and that blocking LILRB1 represents a unique strategy to enhance BiTE molecule therapeutic activity against solid tumors.
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- 2019
8. Functional consequences of the macrophage stimulating protein 689C inflammatory bowel disease risk allele.
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Steven E Kauder, Lydia Santell, Elaine Mai, Lilyan Y Wright, Elizabeth Luis, Elsa N N'Diaye, Jeff Lutman, Navneet Ratti, Susan M Sa, Henry R Maun, Eric Stefanich, Lino C Gonzalez, Robert R Graham, Lauri Diehl, William A Faubion, Mary E Keir, Judy Young, Amitabha Chaudhuri, Robert A Lazarus, and Jackson G Egen
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Medicine ,Science - Abstract
Macrophage stimulating protein (MSP) is a serum growth factor that binds to and activates the receptor tyrosine kinase, Recepteur d'Origine Nantais (RON). A non-synonymous coding variant in MSP (689C) has been associated with genetic susceptibility to both Crohn's disease and ulcerative colitis, two major types of inflammatory bowel disease (IBD) characterized by chronic inflammation of the digestive tract. We investigated the consequences of this polymorphism for MSP-RON pathway activity and IBD pathogenesis.RON expression patterns were examined on mouse and human cells and tissues under normal and disease conditions to identify cell types regulated by MSP-RON. Recombinant MSP variants were tested for their ability to bind and stimulate RON and undergo proteolytic activation. MSP concentrations were quantified in the serum of individuals carrying the MSP 689R and 689C alleles.In intestinal tissue, RON was primarily expressed by epithelial cells under normal and disease conditions. The 689C polymorphism had no impact on the ability of MSP to bind to or signal through RON. In a cohort of normal individuals and IBD patients, carriers of the 689C polymorphism had lower concentrations of MSP in their serum.By reducing the quantities of circulating MSP, the 689C polymorphism, or a variant in linkage disequilibrium with this polymorphism, may impact RON ligand availability and thus receptor activity. Given the known functions of RON in regulating wound healing and our analysis of RON expression patterns in human intestinal tissue, these data suggest that decreased RON activity may impact the efficiency of epithelial repair and thus underlie the increased IBD susceptibility associated with the MSP 689C allele.
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- 2013
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9. Breaking self-tolerance during autoimmunity and cancer immunity: Myeloid cells and type I IFN response regulation
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Kristin V. Tarbell and Jackson G. Egen
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0301 basic medicine ,Innate immune system ,Immunology ,Inflammation ,Cell Biology ,Biology ,medicine.disease_cause ,Autoimmunity ,03 medical and health sciences ,Crosstalk (biology) ,030104 developmental biology ,Immune system ,Immunity ,Self Tolerance ,medicine ,Immunology and Allergy ,medicine.symptom ,Cell activation - Abstract
The generation and regulation of innate immune signals are key determinants of autoimmune pathogenesis. Emerging evidence suggests that parallel processes operating in the setting of solid tumors can similarly determine the balance between tolerance and immunity and ultimately the effectiveness of the antitumor immune response. In both contexts, self-specific responses start with innate immune cell activation that leads to the initial break in self-tolerance, which can be followed by immune response amplification and maturation through innate-adaptive crosstalk, and finally immune-mediated tissue/tumor destruction that can further potentiate inflammation. Of particular importance for these processes is type I IFN, which is induced in response to endogenous ligands, such as self-nucleic acids, and acts on myeloid cells to promote the expansion of autoreactive or tumor-specific T cells and their influx into the target tissue. Evidence from the study of human disease pathophysiology and genetics and mouse models of disease has revealed an extensive and complex network of negative regulatory pathways that has evolved to restrain type I IFN production and activity. Here, we review the overlapping features of self- and tumor-specific immune responses, including the central role that regulators of the type I IFN response and innate immune cell activation play in maintaining tolerance, and discuss how a better understanding of the pathophysiology of autoimmunity can help to identify new approaches to promote immune-mediated tumor destruction.
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- 2018
10. Use of two-photon microscopy to study Leishmania major infection of the skin
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Nathan C. Peters, Leah S. Hohman, Jackson G. Egen, and Matheus B. H. Carneiro
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0301 basic medicine ,Cell type ,Transgene ,Leishmaniasis, Cutaneous ,Mice, Transgenic ,Context (language use) ,General Biochemistry, Genetics and Molecular Biology ,Microbiology ,Mice ,03 medical and health sciences ,Immune system ,Cutaneous leishmaniasis ,medicine ,Animals ,Leishmania major ,Molecular Biology ,Skin ,Microscopy ,biology ,Intracellular parasite ,Leishmania ,biology.organism_classification ,medicine.disease ,Disease Models, Animal ,030104 developmental biology ,Host-Pathogen Interactions ,Immunology ,Microorganisms, Genetically-Modified ,Psychodidae - Abstract
Intra-vital two-photon microscopy (2P-IVM) allows for in-situ investigation of tissue organization, cell behavior and the dynamic interactions between different cell types in their natural environment. This methodology has also expanded our understanding of the immune response against pathogens. Leishmania are protozoan intracellular parasites that have adapted to successfully establish infection within the context of an inflammatory response in the skin following transmission by the bite of an infected sand fly. The generation of fluorescent transgenic parasites coupled with the increased availability of different types of fluorescent transgenic reporter mice has facilitated the study of the host-parasite interaction in the skin, significantly impacting our understanding of cutaneous leishmaniasis. In this review we will discuss 2P-IVM in the context of Leishmania infection of the mouse ear skin and describe a simple and minimally invasive procedure that allows long-term imaging of this host-pathogen interaction.
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- 2017
11. TAZ is required for lung alveolar epithelial cell differentiation after injury
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Guiquan Jia, Clara Posner, Jackson G. Egen, Thirumalai R. Ramalingam, Joseph R. Arron, Hans Brightbill, Tianhe Sun, Hua Zhang, Zhiyu Huang, Min Xu, and Anwesha Dey
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0301 basic medicine ,Organogenesis ,Lung injury ,Bleomycin ,03 medical and health sciences ,Idiopathic pulmonary fibrosis ,0302 clinical medicine ,Fibrosis ,medicine ,Animals ,Humans ,Regeneration ,Progenitor cell ,Lung ,beta Catenin ,Adaptor Proteins, Signal Transducing ,Mice, Knockout ,business.industry ,Stem Cells ,Regeneration (biology) ,Wnt signaling pathway ,Cell Differentiation ,Lung Injury ,General Medicine ,respiratory system ,medicine.disease ,Idiopathic Pulmonary Fibrosis ,Mice, Inbred C57BL ,Organoids ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Alveolar Epithelial Cells ,030220 oncology & carcinogenesis ,Trans-Activators ,Cancer research ,Stem cell ,Transcriptome ,business ,Research Article - Abstract
The lung is a relatively quiescent organ during homeostasis but has a remarkable capacity for repair after injury. Alveolar epithelial type I cells (AEC1s) line airspaces and mediate gas exchange. After injury, they are regenerated by differentiation from their progenitors — alveolar epithelial type II cells (AEC2s) — which also secrete surfactant to maintain surface tension and alveolar patency. While recent studies showed that the maintenance of AEC2 stemness is Wnt dependent, the molecular mechanisms underlying AEC2-AEC1 differentiation in adult lung repair are still incompletely understood. Here, we show that WWTR1 (TAZ) plays a crucial role in AEC differentiation. Using an in vitro organoid culture system, we found that tankyrase inhibition can efficiently block AEC2-AEC1 differentiation, and this effect was due to the inhibition of TAZ. In a bleomycin-induced lung injury model, conditional deletion of TAZ in AEC2s dramatically reduced AEC1 regeneration during recovery, leading to exacerbated alveolar lesions and fibrosis. In patients with idiopathic pulmonary fibrosis (IPF), decreased blood levels of the receptor for advanced glycation end products (RAGE), a biomarker of AEC1 health, were associated with more rapid disease progression. Our findings implicate TAZ as a critical factor involved in AEC2-to-AEC1 differentiation, and hence the maintenance of alveolar integrity after injury.
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- 2019
12. Single-Cell Analyses Inform Mechanisms of Myeloid-Targeted Therapies in Colon Cancer
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Shan Wang, Aaron S. Rapaport, Yao He, Daniel Lu, Xin Yu, Lynn Wang, Yingjiang Ye, Jackson G. Egen, Xueda Hu, Qiao Fang, Ranran Gao, Lei Zhang, Xianwen Ren, Jessica Orf, Aeryon Kim, Wenjun Ouyang, Qiming Zhang, Deepali V. Sawant, Wei Zhang, Chi-Ming Li, Katarzyna M. Skrzypczynska, Kristy Perez, Zhanlong Shen, Jiajinlong Kang, Ziyi Li, Dev Bhatt, Sarah A. O’Brien, Zemin Zhang, and Tao Wang
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Adult ,Male ,China ,Stromal cell ,Myeloid ,medicine.medical_treatment ,Population ,Biology ,CD8-Positive T-Lymphocytes ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Immune system ,medicine ,Tumor Microenvironment ,Animals ,Humans ,Myeloid Cells ,education ,030304 developmental biology ,Aged ,Aged, 80 and over ,0303 health sciences ,education.field_of_study ,Tumor microenvironment ,CD40 ,Base Sequence ,Sequence Analysis, RNA ,Macrophages ,Immunotherapy ,Dendritic Cells ,Middle Aged ,medicine.anatomical_structure ,Colonic Neoplasms ,Cancer research ,biology.protein ,Female ,Single-Cell Analysis ,Colorectal Neoplasms ,030217 neurology & neurosurgery ,Conventional Dendritic Cell - Abstract
Summary Single-cell RNA sequencing (scRNA-seq) is a powerful tool for defining cellular diversity in tumors, but its application toward dissecting mechanisms underlying immune-modulating therapies is scarce. We performed scRNA-seq analyses on immune and stromal populations from colorectal cancer patients, identifying specific macrophage and conventional dendritic cell (cDC) subsets as key mediators of cellular cross-talk in the tumor microenvironment. Defining comparable myeloid populations in mouse tumors enabled characterization of their response to myeloid-targeted immunotherapy. Treatment with anti-CSF1R preferentially depleted macrophages with an inflammatory signature but spared macrophage populations that in mouse and human expresses pro-angiogenic/tumorigenic genes. Treatment with a CD40 agonist antibody preferentially activated a cDC population and increased Bhlhe40+ Th1-like cells and CD8+ memory T cells. Our comprehensive analysis of key myeloid subsets in human and mouse identifies critical cellular interactions regulating tumor immunity and defines mechanisms underlying myeloid-targeted immunotherapies currently undergoing clinical testing.
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- 2019
13. Therapeutic antibodies reveal Notch control of transdifferentiation in the adult lung
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Yan Wu, Yvonne Chinn, Julie Q. Hang, Gladys de Leon Boenig, Søren Warming, Cary D. Austin, Yongmei Chen, Scott Stawicki, Cecilia Chiu, Mike Reichelt, Jeffrey Eastham-Anderson, Heather M. Moore, Daniel Lafkas, John B. Lowe, Christian W. Siebel, Jian Payandeh, Meron Roose-Girma, Meijuan Zhou, Wyne P. Lee, Xiumin Wu, Jackson G. Egen, Christian Siltanen, and Amy L. Shelton
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Male ,JAG1 ,Cell signaling ,Notch signaling pathway ,Biology ,Cell fate determination ,Ligands ,Antibodies ,Mice ,Animals ,Homeostasis ,Humans ,Cell Lineage ,Serrate-Jagged Proteins ,Cilia ,Progenitor cell ,Lung ,Mice, Inbred BALB C ,Multidisciplinary ,Cell Death ,Receptors, Notch ,Calcium-Binding Proteins ,Transdifferentiation ,Membrane Proteins ,Asthma ,Cell biology ,Mice, Inbred C57BL ,Disease Models, Animal ,Cell Tracking ,Cell Transdifferentiation ,Immunology ,Intercellular Signaling Peptides and Proteins ,Respiratory epithelium ,Female ,Goblet Cells ,Jagged-2 Protein ,Cell Division ,Jagged-1 Protein ,Signal Transduction - Abstract
Prevailing dogma holds that cell-cell communication through Notch ligands and receptors determines binary cell fate decisions during progenitor cell divisions, with differentiated lineages remaining fixed. Mucociliary clearance in mammalian respiratory airways depends on secretory cells (club and goblet) and ciliated cells to produce and transport mucus. During development or repair, the closely related Jagged ligands (JAG1 and JAG2) induce Notch signalling to determine the fate of these lineages as they descend from a common proliferating progenitor. In contrast to such situations in which cell fate decisions are made in rapidly dividing populations, cells of the homeostatic adult airway epithelium are long-lived, and little is known about the role of active Notch signalling under such conditions. To disrupt Jagged signalling acutely in adult mammals, here we generate antibody antagonists that selectively target each Jagged paralogue, and determine a crystal structure that explains selectivity. We show that acute Jagged blockade induces a rapid and near-complete loss of club cells, with a concomitant gain in ciliated cells, under homeostatic conditions without increased cell death or division. Fate analyses demonstrate a direct conversion of club cells to ciliated cells without proliferation, meeting a conservative definition of direct transdifferentiation. Jagged inhibition also reversed goblet cell metaplasia in a preclinical asthma model, providing a therapeutic foundation. Our discovery that Jagged antagonism relieves a blockade of cell-to-cell conversion unveils unexpected plasticity, and establishes a model for Notch regulation of transdifferentiation.
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- 2015
14. Abstract A71: Resistance mechanisms limiting the immunostimulatory and antitumor activity of anti-CSF-1 receptor-mediated macrophage depletion
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Daniel Lu, Jackson G. Egen, Katarzyna M. Skrzypczynska, Ian Driver, Jessica Orf, Sarah A. O’Brien, Hong Tan, and Brian Belmontes
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Antitumor activity ,Cancer Research ,Chemistry ,Immunology ,Cancer research ,Macrophage depletion ,Receptor-mediated endocytosis ,Limiting - Abstract
Tumor-associated macrophages (TAMs) are present within the stroma of most solid tumors where they contribute to disease progression through production of tumor and angiogenic growth factors, extracellular matrix remodeling, and suppression of immune responses. As such, depletion of tumor-associated macrophages, for instance through the use of blocking antibodies against the CSF-1 receptor (CSF1R), has been widely explored as a therapeutic approach to both inhibit tumor growth/metastasis and stimulate antitumor immune responses. In the context of immunotherapy, multiple preclinical murine studies have demonstrated that anti-CSF1R meditated macrophage depletion can promote antitumor T-cell responses, synergizing with immune checkpoint inhibitor therapy, such as PD1 blockade, and leading to tumor regression. However, some tumor models appear resistant to these beneficial effects of CSF1R blockade. In order to define potential mechanisms of resistance to CSF1R inhibitors, we evaluated the effects of anti-CSF1R treatment in mice bearing subcutaneous Renca renal cell adenocarcinoma tumors. Despite robust macrophage depletion, this model shows only a modest decrease in tumor volume and minimal effector T-cell recruitment or activation in response to anti-CSF1R therapy. Comprehensive flow cytometry-based immunophenotyping and single-cell RNA sequencing on immune cells isolated from anti-CSF1R- and isotype control-treated Renca tumors revealed shifts in gene expression patterns related to vascular remodeling, hypoxic responses, and enhanced regulatory T-cell activity. These studies indicate macrophage depletion may, under some conditions, have negative effects on antitumor immune responses that could limit the clinical benefit of this therapeutic approach. Citation Format: Katarzyna M. Skrzypczynska, Sarah A. O'Brien, Brian Belmontes, Hong Tan, Jessica Orf, Daniel Lu, Ian Driver, Jackson G. Egen. Resistance mechanisms limiting the immunostimulatory and antitumor activity of anti-CSF-1 receptor-mediated macrophage depletion [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr A71.
- Published
- 2020
15. Abstract PR12: Assessing in vivo mechanisms regulating the therapeutic activity of bi-specific T-cell engager (BiTE®) molecules in immunocompetent mice expressing a chimeric human/mouse CD3ϵ receptor
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Famke Aeffner, Jason Eng, Brian Belmontes, John M. Harrold, Mercedesz Balazs, Melissa M. Martin, Jackson G. Egen, Matthew Chun, Sarah A. O’Brien, Brandy Alexander, Jude Canon, Alice Bakker, Angela Coxon, Jason DeVoss, Olivier Nolan-Stevaux, Wendy Zhong, Kevin Cook, Hong Tan, and Danny Chui
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Cancer Research ,biology ,T cell ,medicine.medical_treatment ,CD3 ,Immunology ,Immunotherapy ,CD19 ,medicine.anatomical_structure ,Immune system ,Antigen ,In vivo ,biology.protein ,medicine ,Cancer research ,Cytotoxic T cell - Abstract
The development and success of Blincyto®, a Bi-Specific T cell Engager (BiTE®), to treat acute lymphoblastic leukemia has expanded the class of anticancer immunotherapy agents. BiTE® molecules consist of a single-chain Fc antibody containing tandem single-chain variable fragments (scFv) recognizing the CD3 receptor on T lymphocytes and a tumor-associated antigen and induce redirected T-cell cytotoxicity and tumor cell lysis. Despite the clinically validated efficacy of BiTE® molecules, there has been little elucidation of the parameters governing their in vivo activity. This is due, in part, to a lack of immunocompetent murine tumor models that allow for engagement of endogenous T cells in the context of an intact immune system, which more accurately mimic the human therapeutic setting. We have developed a genetically engineered mouse model (huCD3 mouse) in which a human/mouse chimeric CD3ϵ receptor recognized by BiTE® molecules was engineered into the mouse CD3ϵ genomic locus. Here, we characterize the immune cell distribution of the huCD3 mouse and utilize BiTE® molecules and syngeneic tumor models to elucidate pharmacokinetic, pharmacodynamic, and efficacy relationships in vivo. The peripheral B and T cell distribution profile of huCD3 mice and WT littermates are comparable, but T cells isolated from huCD3 mice express lower levels of. In T cell-dependent cytotoxic (TDCC) assays, an anti-huEpCAM BiTE® molecule exhibited similar potency against MC38 mouse cells expressing human EpCAM co-cultured with T cells from the huCD3 mice or a human donor, if mouse T-cells were preactivated in vitro. In vivo, MC38-huEpCAM tumors grew robustly and anti-huEpCAM BiTEÂ treatment resulted in dose-dependent tumor growth inhibition, with several tumor-free animals at higher doses. Flow cytometry analysis of disaggregated tumors and serum cytokine analysis indicated that BiTE® treatment resulted in T-cell activation and a cytokine response at doses that correlate with tumor regression. In vivo studies were also performed using B16F10-huEPCAM cells, which generate tumors with reduced T-cell infiltration compared to MC38-huEpCAM. Additionally, we used WT mice reconstituted with different ratios of huCD3e and WT bone marrow to investigate the T-cell number requirement for optimal BiTE®-mediated efficacy. We also evaluated the efficacy of an anti-mouse CD19 BiTE® molecule against MC38-CD19 tumor cells to compare the requirements for antitumor efficacy versus normal B-cell depletion in the blood and in lymphoid organs. Finally, we performed a rational combination study using BiTE® molecules and a PD1 inhibitor, demonstrating that this combination can lead to the eradication of poorly T cell-infiltrated solid tumors. These data begin to elucidate the in vivo mechanisms regulating the efficacy of BiTE® molecules under physiologically relevant conditions. This abstract is also being presented as Poster A29. Citation Format: Brian Belmontes, Hong Tan, Wendy Zhong, Danny Chui, Kevin Cook, Sarah O'Brien, Melissa Martin, Brandy Alexander, Jason Eng, John Harrold, Famke Aeffner, Matthew Chun, Alice Bakker, Mercedesz Balazs, Jason DeVoss, Angela Coxon, Jude Canon, Jackson Egen, Olivier Nolan-Stevaux. Assessing in vivo mechanisms regulating the therapeutic activity of bi-specific T-cell engager (BiTE®) molecules in immunocompetent mice expressing a chimeric human/mouse CD3ϵ receptor [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr PR12.
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- 2020
16. Correction: LILRB1 Blockade Enhances Bispecific T Cell Engager Antibody–Induced Tumor Cell Killing by Effector CD8+ T Cells
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Aeryon Kim, Chia-Jung Han, Ian Driver, Aleksandra Olow, Andrew K. Sewell, Zemin Zhang, Wenjun Ouyang, Jackson G. Egen, and Xin Yu
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Leukocyte Immunoglobulin-like Receptor B1 ,Antigens, CD ,T-Lymphocyte Subsets ,Neoplasms ,Antibodies, Bispecific ,Immunology ,Tumor Cells, Cultured ,Humans ,Immunology and Allergy ,Immunotherapy ,Lymphocyte Activation ,Corrections ,T-Lymphocytes, Cytotoxic - Abstract
Elicitation of tumor cell killing by CD8
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- 2019
17. Pathogen-Related Differences in the Abundance of Presented Antigen Are Reflected in CD4+ T Cell Dynamic Behavior and Effector Function in the Lung
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Michael Y. Gerner, Jackson G. Egen, Wolfgang Kastenmüller, Nienke Vrisekoop, Parizad Torabi-Parizi, and Ronald N. Germain
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CD4-Positive T-Lymphocytes ,Adoptive cell transfer ,T cell ,Immunology ,Antigen presentation ,Receptors, Antigen, T-Cell ,Lymphocyte Activation ,Major histocompatibility complex ,Article ,Interferon-gamma ,Mice ,Orthomyxoviridae Infections ,Antigen ,Cell Movement ,medicine ,Animals ,Immunology and Allergy ,IL-2 receptor ,Lung ,Tuberculosis, Pulmonary ,Inflammation ,Antigen Presentation ,biology ,Tumor Necrosis Factor-alpha ,Effector ,T-cell receptor ,Cell Differentiation ,Mycobacterium tuberculosis ,Orthomyxoviridae ,Adoptive Transfer ,Mycobacterium bovis ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Liver ,biology.protein ,Cytokines ,Lymph Nodes - Abstract
Exposure to pathogens in the periphery elicits effector T cell differentiation in local lymph nodes followed by migration of activated T cells to and within the infected site. However, the relationships among pathogen abundance, Ag display on MHC molecules, effector T cell dynamics, and functional responses at the infected sites are incompletely characterized. In this study, we compared CD4+ T cell effector dynamics and responses during pulmonary mycobacterial infection versus acute influenza infection. Two-photon imaging together with in situ as well as ex vivo analysis of cytokine production revealed that the proportion of migration-arrested, cytokine-producing effector T cells was dramatically higher in the influenza-infected lungs due to substantial differences in Ag abundance in the two infectious states. Despite the marked inflammatory conditions associated with influenza infection, histocytometric analysis showed that cytokine production was focal, with a restriction to areas of significant Ag burden. Optimal effector function is thus constrained by the availability of TCR ligands, pointing to the value of increasing Ag stimulation rather than effector numbers in harnessing CD4+ T cells for therapeutic purposes in such conditions.
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- 2014
18. Tuning of Antigen Sensitivity by T Cell Receptor-Dependent Negative Feedback Controls T Cell Effector Function in Inflamed Tissues
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Tetsuya Honda, Jackson G. Egen, Parizad Torabi-Parizi, Ronald N. Germain, Wolfgang Kastenmüller, and Tim Lämmermann
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Effector ,medicine.medical_treatment ,T cell ,T-cell receptor ,Antigen presentation ,Immunology ,Biology ,Cell biology ,Immune system ,Cytokine ,medicine.anatomical_structure ,Infectious Diseases ,Antigen ,medicine ,Immunology and Allergy ,Receptor - Abstract
Activated T cells must mediate effector responses sufficient to clear pathogens while avoiding excessive tissue damage. Here we have combined dynamic intravital microscopy with ex vivo assessments of T cell cytokine responses to generate a detailed spatiotemporal picture of CD4+ T cell effector regulation in the skin. In response to antigen, effector T cells arrested transiently on antigen presenting cells, briefly producing cytokine and then resuming migration. Antigen recognition led to PD-1 upregulation of the programmed death-1 (PD-1) glycoprotein by T cells and blocking its canonical ligand, programmed death-ligand 1 (PD-L1), lengthened the duration of migration arrest and cytokine production, showing that PD-1 interaction with PD-L1 is a major negative feedback regulator of antigen responsiveness. We speculate that the immune system employs a mechanism involving T cell recruitment, transient activation, and rapid desensitization, allowing the T cell response to rapidly adjust to changes in antigen presentation and minimize collateral injury to the host.
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- 2014
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19. Abstract 2803: CSF-1 receptor-mediated macrophage depletion can induce immunomodulatory resistance mechanisms in murine tumor models
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Ian Driver, Brian Belmontes, Jackson G. Egen, Katarzyna M. Skrzypczynska, Daniel R. Lu, Hong Tan, Jessica Orf, and Sarah A. O’Brien
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Cancer Research ,Regulatory T cell ,T cell ,medicine.medical_treatment ,Cell ,Cancer ,Immunotherapy ,Biology ,medicine.disease ,Metastasis ,medicine.anatomical_structure ,Immune system ,Immunophenotyping ,Oncology ,Cancer research ,medicine - Abstract
Tumor associated macrophages (TAMs) are present within the stroma of most solid tumors where they can act to inhibit immune responses and promote disease progression through expression of immunosuppressive factors and modulation of tumor stroma. Tumor immunotherapies aimed at depletion of TAMs, for instance through the use of blocking antibodies against the CSF1 receptor (CSF1R), have been widely explored, with multiple studies demonstrating that blocking TAM function can inhibit tumor growth/metastasis and stimulate anti-tumor immunity. In order to further dissect the functions of TAM populations and define conditions under which antiCSF1R immunotherapy may have benefit, we evaluated the effect of antiCSF1R treatment on multiple subcutaneous murine tumor models with varying dosing parameters. Despite robust macrophage depletion, some tumor models, such as Renca renal cell adenocarcinoma, showed only a modest change in tumor volume and minimal effector T cell recruitment or activation in response to anti-CSF1R therapy. Comprehensive flow cytometry-based immunophenotyping and single-cell RNA sequencing on immune cells isolated from antiCSF1R and isotype control-treated Renca tumors revealed shifts in gene expression patterns related to vascular remodeling, hypoxic responses, and enhanced regulatory T cell activity. These studies indicate macrophage depletion may, under some conditions, result in compensatory anti-tumor immune responses that could limit the clinical benefit of this therapeutic approach. Citation Format: Sarah A. O'Brien, Katarzyna Skrzypczynska, Jessica Orf, Brian Belmontes, Hong Tan, Daniel Lu, Ian Driver, Jackson Egen. CSF-1 receptor-mediated macrophage depletion can induce immunomodulatory resistance mechanisms in murine tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2803.
- Published
- 2019
20. Peripheral Prepositioning and Local CXCL9 Chemokine-Mediated Guidance Orchestrate Rapid Memory CD8+ T Cell Responses in the Lymph Node
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Ze Wang, Marlene Brandes, Ronald N. Germain, Jasmin Herz, Wolfgang Kastenmüller, and Jackson G. Egen
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Chemokine ,Receptors, CXCR3 ,medicine.medical_treatment ,Green Fluorescent Proteins ,Immunology ,Vaccinia virus ,CD8-Positive T-Lymphocytes ,Biology ,Chemokine CXCL9 ,Article ,Interferon-gamma ,Mice ,Receptors, CCR ,Immune system ,Cell Movement ,Memory cell ,Vaccinia ,medicine ,Animals ,Immunology and Allergy ,Cytotoxic T cell ,Lymph node ,Mice, Knockout ,Effector ,Macrophages ,Flow Cytometry ,Microscopy, Fluorescence, Multiphoton ,Infectious Diseases ,Cytokine ,medicine.anatomical_structure ,biology.protein ,Lymph Nodes ,Immunologic Memory ,CD8 - Abstract
SummaryAfter an infection, the immune system generates long-lived memory lymphocytes whose increased frequency and altered state of differentiation enhance host defense against reinfection. Recently, the spatial distribution of memory cells was found to contribute to their protective function. Effector memory CD8+ T cells reside in peripheral tissue sites of initial pathogen encounter, in apparent anticipation of reinfection. Here we show that within lymph nodes (LNs), memory CD8+ T cells were concentrated near peripheral entry portals of lymph-borne pathogens, promoting rapid engagement of infected sentinel macrophages. A feed-forward CXCL9-dependent circuit provided additional chemotactic cues that further increase local memory cell density. Memory CD8+ T cells also produced effector responses to local cytokine triggers, but their dynamic behavior differed from that seen after antigen recognition. These data reveal the distinct localization and dynamic behavior of naive versus memory T cells within LNs and how these differences contribute to host defense.
- Published
- 2013
21. CRIg mediates early Kupffer cell responses to adenovirus
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Jeffrey Eastham-Anderson, Menno van Lookeren Campagne, Peter Gribling, Lauri Diehl, Anusha Ponakala, Jeannie Q. He, Kenneth J. Katschke, Eric Suto, Jackson G. Egen, Wyne P. Lee, and László G. Kömüves
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Programmed cell death ,Kupffer Cells ,Adenoviridae Infections ,viruses ,Phagocytosis ,Immunology ,Complement receptor ,Biology ,medicine.disease_cause ,Adenoviridae ,Mice ,medicine ,Animals ,Immunology and Allergy ,Receptor ,Complement Activation ,Mice, Knockout ,Microscopy, Confocal ,Innate immune system ,Cell Death ,Kupffer cell ,Cell Biology ,Flow Cytometry ,Immunohistochemistry ,Receptors, Complement ,Complement system ,Cell biology ,medicine.anatomical_structure - Abstract
CRIg plays a critical role in regulating Kupffer cell function and survival in response to adenovirus infection. Whereas adenoviral vectors are known to activate the complement cascade, leading to fixation of C3 proteins to the viral capsid, the consequences of this activation for viral clearance from the circulation are not known. Liver KCs, the macrophage population responsible for early uptake and elimination of many blood-borne pathogens, express CRIg, a complement receptor for C3 proteins. Here, we find that CRIg is important for the early elimination of C3-coated adenoviral vectors from the sinusoidal bloodstream by KCs. We further demonstrate that by acting as a critical receptor for adenovirus phagocytosis, CRIg plays an important role in regulating virus-induced KC death and depletion of these cells from the liver sinusoidal lumen. Our study thus identifies a critical pathway regulating KC function and survival in response to systemic viral infection.
- Published
- 2013
22. αEβ7 Integrin Identifies Subsets of Pro-Inflammatory Colonic CD4+ T Lymphocytes in Ulcerative Colitis
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Christopher A, Lamb, John C, Mansfield, Gaik W, Tew, Deena, Gibbons, Anna K, Long, Peter, Irving, Lauri, Diehl, Jeff, Eastham-Anderson, Maria B, Price, Graeme, O'Boyle, David E J, Jones, Sharon, O'Byrne, Adrian, Hayday, Mary E, Keir, Jackson G, Egen, and John A, Kirby
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Adult ,CD4-Positive T-Lymphocytes ,Male ,Integrins ,regulatory T cell ,Colon ,Real-Time Polymerase Chain Reaction ,etrolizumab ,Th1 ,Young Adult ,CD4+ T cell ,inflammatory bowel disease ,mucosal immunology ,intraepithelial lymphocytes ,effector T cell ,cytokine ,Humans ,Th17/1 ,Aged ,ulcerative colitis ,Middle Aged ,Flow Cytometry ,Treg ,αEβ7 integrin ,Case-Control Studies ,helper T cell ,CD103 ,Cytokines ,Colitis, Ulcerative ,Female ,Original Article ,Th17 - Abstract
Background and Aims: The αEβ7 integrin is crucial for retention of T lymphocytes at mucosal surfaces through its interaction with E-cadherin. Pathogenic or protective functions of these cells during human intestinal inflammation, such as ulcerative colitis [UC], have not previously been defined, with understanding largely derived from animal model data. Defining this phenotype in human samples is important for understanding UC pathogenesis and is of translational importance for therapeutic targeting of αEβ7–E-cadherin interactions. Methods: αEβ7+ and αEβ7− colonic T cell localization, inflammatory cytokine production and expression of regulatory T cell-associated markers were evaluated in cohorts of control subjects and patients with active UC by immunohistochemistry, flow cytometry and real-time PCR of FACS-purified cell populations. Results: CD4+αEβ7+ T lymphocytes from both healthy controls and UC patients had lower expression of regulatory T cell-associated genes, including FOXP3, IL-10, CTLA-4 and ICOS in comparison with CD4+αEβ7− T lymphocytes. In UC, CD4+αEβ7+ lymphocytes expressed higher levels of IFNγ and TNFα in comparison with CD4+αEβ7− lymphocytes. Additionally the CD4+αEβ7+ subset was enriched for Th17 cells and the recently described Th17/Th1 subset co-expressing both IL-17A and IFNγ, both of which were found at higher frequencies in UC compared to control. Conclusion: αEβ7 integrin expression on human colonic CD4+ T cells was associated with increased production of pro-inflammatory Th1, Th17 and Th17/Th1 cytokines, with reduced expression of regulatory T cell-associated markers. These data suggest colonic CD4+αEβ7+ T cells are pro-inflammatory and may play a role in UC pathobiology.
- Published
- 2016
23. IgE+ memory B cells and plasma cells generated through a germinal-center pathway
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Meijuan Zhou, Wyne P. Lee, Oezcan Talay, Ena Ladi, Jackson G. Egen, Min Xu, Cary D. Austin, Donghong Yan, Elizabeth E M Straney, Lawren C. Wu, and Hans Brightbill
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Adoptive cell transfer ,CD40 ,biology ,medicine.diagnostic_test ,Chemistry ,Immunology ,B-cell receptor ,Naive B cell ,Germinal center ,Immunoglobulin E ,Molecular biology ,Flow cytometry ,biology.protein ,medicine ,Immunology and Allergy ,Antibody - Abstract
Immunoglobulin E (IgE) antibodies are pathogenic in asthma and allergic diseases, but the in vivo biology of IgE-producing (IgE(+)) cells is poorly understood. A model of the differentiation of IgE(+) B cells proposes that IgE(+) cells develop through a germinal-center IgG1(+) intermediate and that IgE memory resides in the compartment of IgG1(+) memory B cells. Here we have used a reporter mouse expressing green fluorescent protein associated with membrane IgE transcripts (IgE-GFP) to assess in vivo IgE responses. In contrast to the IgG1-centered model of IgE switching and memory, we found that IgE(+) cells developed through a germinal-center IgE(+) intermediate to form IgE(+) memory B cells and plasma cells. Our studies delineate a new model for the in vivo biology of IgE switching and memory.
- Published
- 2012
24. Transient neutropenia after granulocyte-colony stimulating factor administration is associated with neutrophil accumulation in pulmonary vasculature
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Catherine E. Dejesus, Xin Tian, Christian A. Combs, Xavier Alvarez, Zu Xi Yu, Daniela Malide, Robert E. Donahue, Mark E. Metzger, and Jackson G. Egen
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Male ,Pulmonary Circulation ,Cancer Research ,medicine.medical_specialty ,Pathology ,Neutropenia ,Neutrophils ,Mice, Transgenic ,Spleen ,CD18 ,Article ,Green fluorescent protein ,Mice ,Internal medicine ,Granulocyte Colony-Stimulating Factor ,Genetics ,medicine ,Animals ,Lung ,Molecular Biology ,Kidney ,business.industry ,Cell Biology ,Hematology ,medicine.disease ,Macaca mulatta ,Blood Cell Count ,Granulocyte colony-stimulating factor ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Endocrinology ,Pulmonary vasculature ,business - Abstract
Objective To better define the nature of the transient neutropenia shortly following granulocyte-colony stimulating factor (G-CSF) administration. Materials and Methods To evaluate the disappearance of neutrophils, we investigated neutrophil trafficking. Ratios of neutrophil number to background cellularity for C57BL/6 LysM-EGFP knock-in mice and rhesus macaques were determined in the lung, liver, spleen, and kidney after G-CSF administration. Results For the C57BL/6 LysM-EGFP knock-in mice, the enhanced green fluorescent protein expression (EGFP + ) cells increased in the lung and spleen within 15 minutes of administering 50 μg/kg G-CSF subcutaneously, and continued to increase in the lung and spleen from 15 minutes to 30 minutes. At 240 minutes, the pulmonary infiltrate declined to a level comparable to the level at 15 minutes, while in the spleen EGFP + cells continued to increase. For rhesus macaques, CD18 + cells also significantly increased in the lung 30 minutes after administration of 10 μg/kg G-CSF subcutaneously compared to the control level. Conclusions These results suggest that the transient neutropenia following G-CSF administration in the mouse and nonhuman primate is associated with an accumulation of neutrophils within pulmonary and splenic vasculature.
- Published
- 2011
25. Trafficking of a Dual-Modality Magnetic Resonance and Fluorescence Imaging Superparamagnetic Iron Oxide-Based Nanoprobe to Lymph Nodes
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Peter L. Choyke, Ronald N. Germain, Jackson G. Egen, Celeste A. S. Regino, Marcelino Bernardo, Peter J. Dobson, Martin W. Brechbiel, and Ambika Bumb
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Cancer Research ,Pathology ,medicine.medical_specialty ,Fluorescence-lifetime imaging microscopy ,Sentinel lymph node ,Mice, Nude ,Fluorescence ,Article ,law.invention ,Mice ,In vivo ,Confocal microscopy ,law ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Magnetite Nanoparticles ,Lymph node ,Microscopy, Confocal ,Staining and Labeling ,integumentary system ,Chemistry ,Dextrans ,Sentinel node ,Silicon Dioxide ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Oncology ,Nanoparticles ,Lymph Nodes ,Molecular imaging ,Ex vivo - Abstract
This study aims to develop and characterize the trafficking of a dual-modal agent that identifies primary draining or sentinel lymph node (LN). Herein, a dual-reporting silica-coated iron oxide nanoparticle (SCION) is developed. Nude mice were imaged by magnetic resonance (MR) and optical imaging and axillary LNs were harvested for histological analysis. Trafficking through lymphatics was observed with intravital and ex vivo confocal microscopy of popliteal LNs in B6-albino, CD11c-EYFP, and lys-EGFP transgenic mice. In vivo, SCION allows visualization of LNs. The particle’s size and surface functionality play a role in its passive migration from the intradermal injection site and its minimal uptake by CD11c+ dendritic cells and CD169+ and lys+ macrophages. After injection, SCION passively migrates to LNs without macrophage uptake and then can be used to image LN(s) by MRI and fluorescence. Thus, SCION can potentially be developed for use in sentinel node resections or for intralymphatic drug delivery.
- Published
- 2010
26. Sphingosine-1-phosphate mobilizes osteoclast precursors and regulates bone homeostasis
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Yukihiko Saeki, Jackson G. Egen, Jean Vacher, Martin Meier-Schellersheim, Ronald N. Germain, Richard L. Proia, Masaru Ishii, and Frederick Klauschen
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musculoskeletal diseases ,Bone density ,Ovariectomy ,Osteoclasts ,Biology ,Bone and Bones ,Monocytes ,Article ,Bone resorption ,Cell Line ,Bone remodeling ,Mice ,Bone Density ,Sphingosine ,Osteoclast ,medicine ,Animals ,Homeostasis ,Cell Lineage ,Bone Resorption ,Bone mineral ,Multidisciplinary ,Fingolimod Hydrochloride ,Chemotaxis ,Cell biology ,Mice, Inbred C57BL ,Receptors, Lysosphingolipid ,medicine.anatomical_structure ,Positive chemotaxis ,Propylene Glycols ,RANKL ,Immunology ,biology.protein ,Osteoporosis ,Female ,Lysophospholipids - Abstract
Osteoclasts are the only somatic cells with bone-resorbing capacity and, as such, they have a critical role not only in normal bone homeostasis (called 'bone remodelling') but also in the pathogenesis of bone destructive disorders such as rheumatoid arthritis and osteoporosis. A major focus of research in the field has been on gene regulation by osteoclastogenic cytokines such as receptor activator of NF-kappaB-ligand (RANKL, also known as TNFSF11) and TNF-alpha, both of which have been well documented to contribute to osteoclast terminal differentiation. A crucial process that has been less well studied is the trafficking of osteoclast precursors to and from the bone surface, where they undergo cell fusion to form the fully differentiated multinucleated cells that mediate bone resorption. Here we report that sphingosine-1-phosphate (S1P), a lipid mediator enriched in blood, induces chemotaxis and regulates the migration of osteoclast precursors not only in culture but also in vivo, contributing to the dynamic control of bone mineral homeostasis. Cells with the properties of osteoclast precursors express functional S1P(1) receptors and exhibit positive chemotaxis along an S1P gradient in vitro. Intravital two-photon imaging of bone tissues showed that a potent S1P(1) agonist, SEW2871, stimulated motility of osteoclast precursor-containing monocytoid populations in vivo. Osteoclast/monocyte (CD11b, also known as ITGAM) lineage-specific conditional S1P(1) knockout mice showed osteoporotic changes due to increased osteoclast attachment to the bone surface. Furthermore, treatment with the S1P(1) agonist FTY720 relieved ovariectomy-induced osteoporosis in mice by reducing the number of mature osteoclasts attached to the bone surface. Together, these data provide evidence that S1P controls the migratory behaviour of osteoclast precursors, dynamically regulating bone mineral homeostasis, and identifies a critical control point in osteoclastogenesis that may have potential as a therapeutic target.
- Published
- 2009
27. Quantification of the infectious dose ofLeishmania majortransmitted to the skin by single sand flies
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Alain Debrabant, Nágila Francinete Costa Secundino, David L. Sacks, Nathan C. Peters, Jackson G. Egen, Shaden Kamhawi, Nicola Kimblin, Phillip G. Lawyer, and Michael P. Fay
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Leishmaniasis, Cutaneous ,Transfection ,Polymerase Chain Reaction ,Parasite load ,Mice ,parasitic diseases ,medicine ,Animals ,Parasite hosting ,Leishmania major ,Psychodidae ,DNA Primers ,Skin ,Mice, Inbred BALB C ,Multidisciplinary ,Base Sequence ,biology ,Infectious dose ,fungi ,Leishmaniasis ,DNA, Protozoan ,Biological Sciences ,medicine.disease ,biology.organism_classification ,Leishmania ,Virology ,Recombinant Proteins ,Insect Vectors ,Mice, Inbred C57BL ,Luminescent Proteins ,Vector (epidemiology) ,Female - Abstract
Leishmaniasis is transmitted between mammalian hosts by the bites of bloodsucking vector sand flies. The dose of parasites transmitted to the mammalian host has never been directly determined. We developed a real-time PCR-based method to determine the number ofLeishmania majorparasites inoculated into the ears of living mice during feeding by individual infected flies (Phlebotomus duboscqi). The number of parasites transmitted varied over a wide range in the 58 ears in whichLeishmaniawere detected and demonstrated a clear bimodal distribution. Most of the infected mice were inoculated with a low dose of 1,000 and up to 100,000 cells. High-dose transmission was associated with a heavy midgut infection of >30,000 parasites, incomplete blood feeding, and transmission of a high percentage of the parasite load in the fly. To test the impact of inoculum size on infection outcome, we compared representative high- (5,000) and low- (100) dose intradermal needle infections in the ears of C57BL/6 mice. To mimic natural transmission, we used sand fly-derived metacyclic forms ofL. majorand preexposed the injection site to the bites of uninfected flies. Large lesions developed rapidly in the ears of mice receiving the high-dose inoculum. The low dose resulted in only minor pathology but a higher parasite titer in the chronic phase, and it established the host as an efficient long-term reservoir of infection back to vector sand flies.
- Published
- 2008
28. Macrophage and T Cell Dynamics during the Development and Disintegration of Mycobacterial Granulomas
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Alan Sher, Jackson G. Egen, Antonio Gigliotti Rothfuchs, Ronald N. Germain, Carl G. Feng, Nathalie Winter, Sher, Alan, Germain, Ronald N, National Institutes of Health, Génétique mycobactérienne - Mycobacterial genetics, Institut Pasteur [Paris], and Intramural Research Program of NIAID, NIH, DHHS
- Subjects
Kupffer Cells ,T cell ,Immunology ,Population ,Cell ,HUMDISEASE ,Biology ,Lymphocyte Activation ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,T-Lymphocyte Subsets ,hemic and lymphatic diseases ,medicine ,Animals ,Tuberculosis ,Immunology and Allergy ,Macrophage ,education ,030304 developmental biology ,0303 health sciences ,education.field_of_study ,Granuloma ,Tumor Necrosis Factor-alpha ,Effector ,Macrophages ,Microbiology and Parasitology ,medicine.disease ,Mycobacterium bovis ,Microbiologie et Parasitologie ,3. Good health ,Cell biology ,Mice, Inbred C57BL ,[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,Infectious Diseases ,medicine.anatomical_structure ,Liver ,CELLIMMUNO ,Tumor necrosis factor alpha ,030215 immunology - Abstract
International audience; Granulomas play a key role in host protection against mycobacterial pathogens, with their breakdown contributing to exacerbated disease. To better understand the initiation and maintenance of these structures, we employed both high-resolution multiplex static imaging and intravital multiphoton microscopy of Mycobacterium bovis BCG-induced liver granulomas. We found that Kupffer cells directly capture blood-borne bacteria and subsequently nucleate formation of a nascent granuloma by recruiting both uninfected liver-resident macrophages and blood-derived monocytes. Within the mature granuloma, these myeloid cell populations formed a relatively immobile cellular matrix that interacted with a highly dynamic effector T cell population. The efficient recruitment of these T cells was highly dependent on TNF-alpha-derived signals, which also maintained the granuloma structure through preferential effects on uninfected macrophage populations. By characterizing the migration of both innate and adaptive immune cells throughout the process of granuloma development, these studies provide a new perspective on the cellular events involved in mycobacterial containment and escape.
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- 2008
29. T H 2 and T H 17 inflammatory pathways are reciprocally regulated in asthma
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Janet Jackman, Emma Doran, Jackson G. Egen, Peter Bradding, Chandra M. Ohri, Kevin M. Hart, Joshua Sciurba, Lawren C. Wu, Thirumalai R. Ramalingam, Robert W. Thompson, Kevin M. Vannella, Joseph R. Arron, Thomas A. Wynn, Lee A. Borthwick, Claire A. Butler, Deepti R. Nagarkar, Aarti Shikotra, Beverley Hargadon, Liam G Heaney, Salman Siddiqui, Guiquan Jia, Sandra White, Alexander R. Abbas, David F. Choy, and Richard L. Gieseck
- Subjects
Cytokine Suppression ,business.industry ,General Medicine ,Hyperplasia ,medicine.disease ,Mucus ,Interleukin 13 ,Immunology ,Medicine ,Eosinophilia ,Interleukin 17 ,medicine.symptom ,Signal transduction ,business ,Asthma - Abstract
Increasing evidence suggests that asthma is a heterogeneous disorder regulated by distinct molecular mechanisms. In a cross-sectional study of asthmatics of varying severity (n = 51), endobronchial tissue gene expression analysis revealed three major patient clusters: TH2-high, TH17-high, and TH2/17-low. TH2-high and TH17-high patterns were mutually exclusive in individual patient samples, and their gene signatures were inversely correlated and differentially regulated by interleukin-13 (IL-13) and IL-17A. To understand this dichotomous pattern of T helper 2 (TH2) and TH17 signatures, we investigated the potential of type 2 cytokine suppression in promoting TH17 responses in a preclinical model of allergen-induced asthma. Neutralization of IL-4 and/or IL-13 resulted in increased TH17 cells and neutrophilic inflammation in the lung. However, neutralization of IL-13 and IL-17 protected mice from eosinophilia, mucus hyperplasia, and airway hyperreactivity and abolished the neutrophilic inflammation, suggesting that combination therapies targeting both pathways may maximize therapeutic efficacy across a patient population comprising both TH2 and TH17 endotypes.
- Published
- 2015
30. CXCL14 is a candidate biomarker for Hedgehog signalling in idiopathic pulmonary fibrosis
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Joseph R. Arron, Ivan Peng, Jason DeVoss, Harold R. Collard, Alexander R. Abbas, Elsa N N'Diaye, Paul J. Wolters, Guiquan Jia, Murat Yaylaoglu, Jackson G. Egen, Daryle Depianto, Sanjay Chandriani, and Heather M. Moore
- Subjects
0301 basic medicine ,Pulmonary and Respiratory Medicine ,Male ,Pathology ,medicine.medical_specialty ,Pyridines ,Vismodegib ,Antineoplastic Agents ,03 medical and health sciences ,Idiopathic pulmonary fibrosis ,Neoplasms ,medicine ,Animals ,Humans ,Anilides ,Hedgehog Proteins ,Sonic hedgehog ,CXCL14 ,Hedgehog ,Lung ,Cells, Cultured ,Aged ,biology ,business.industry ,Cancer ,respiratory system ,Middle Aged ,medicine.disease ,Idiopathic Pulmonary Fibrosis ,respiratory tract diseases ,Up-Regulation ,Mice, Inbred C57BL ,030104 developmental biology ,medicine.anatomical_structure ,Gene Expression Regulation ,biology.protein ,Biomarker (medicine) ,Female ,business ,Chemokines, CXC ,Biomarkers ,medicine.drug ,Signal Transduction - Abstract
Background Idiopathic pulmonary fibrosis (IPF) is associated with aberrant expression of developmental pathways, including Hedgehog (Hh). As Hh signalling contributes to multiple pro-fibrotic processes, Hh inhibition may represent a therapeutic option for IPF. However, no non-invasive biomarkers are available to monitor lung Hh activity. Methods We assessed gene and protein expression in IPF and control lung biopsies, mouse lung, fibroblasts stimulated in vitro with sonic hedgehog (SHh), and plasma in IPF patients versus controls, and cancer patients before and after treatment with vismodegib, a Hh inhibitor. Results Lung tissue from IPF patients exhibited significantly greater expression of Hh-related genes versus controls. The gene most significantly upregulated in both IPF lung biopsies and fibroblasts stimulated in vitro with SHh was CXCL14 , which encodes a soluble secreted chemokine whose expression is inhibited in vitro by the addition of vismodegib. CXCL14 expression was induced by SHh overexpression in mouse lung. Circulating CXCL14 protein levels were significantly higher in plasma from IPF patients than controls. In cancer patients, circulating CXCL14 levels were significantly reduced upon vismodegib treatment. Conclusions CXCL14 is a systemic biomarker that could be used to identify IPF patients with increased Hh pathway activity and monitor the pharmacodynamic effects of Hh antagonist therapy in IPF. Trial registration number Post-results, NCT00968981.
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- 2015
31. Heterogeneous gene expression signatures correspond to distinct lung pathologies and biomarkers of disease severity in idiopathic pulmonary fibrosis
- Author
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Paul J. Wolters, Jasleen Kukreja, Satyajit K Karnik, Daryle Depianto, Alexander R. Abbas, Harold R. Collard, Sabyasachi Biswas, Steven E. Kauder, Connie Ha, Elsa N N'Diaye, Guiquan Jia, Zora Modrusan, Patrick Caplazi, Michael A. Matthay, Sanjay Chandriani, Jackson G. Egen, and Joseph R. Arron
- Subjects
Male ,Pathology ,Respiratory System ,Disease ,Severity of Illness Index ,Idiopathic pulmonary fibrosis ,80 and over ,2.1 Biological and endogenous factors ,Aetiology ,Lung ,Cancer ,Aged, 80 and over ,screening and diagnosis ,B-Lymphocytes ,Middle Aged ,respiratory system ,Prognosis ,Immunohistochemistry ,Detection ,medicine.anatomical_structure ,Respiratory ,Disease Progression ,Biomarker (medicine) ,Female ,Matrix Metalloproteinase 3 ,4.2 Evaluation of markers and technologies ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Clinical Sciences ,and over ,Autoimmune Disease ,Rare Diseases ,medicine ,Humans ,CXCL13 ,Pathological ,Aged ,business.industry ,Proportional hazards model ,Gene Expression Profiling ,medicine.disease ,Chemokine CXCL13 ,Fold change ,Idiopathic Pulmonary Fibrosis ,4.1 Discovery and preclinical testing of markers and technologies ,respiratory tract diseases ,Gene Expression Regulation ,business - Abstract
© 2014, BMJ Publishing Group. All rights reserved. Background: There is microscopic spatial and temporal heterogeneity of pathological changes in idiopathic pulmonary fibrosis (IPF) lung tissue, which may relate to heterogeneity in pathophysiological mediators of disease and clinical progression. We assessed relationships between gene expression patterns, pathological features, and systemic biomarkers to identify biomarkers that reflect the aggregate disease burden in patients with IPF. Methods: Gene expression microarrays (N=40 IPF; 8 controls) and immunohistochemical analyses (N=22 IPF; 8 controls) of lung biopsies. Clinical characterisation and blood biomarker levels of MMP3 and CXCL13 in a separate cohort of patients with IPF (N=80). Results: 2940 genes were significantly differentially expressed between IPF and control samples (|fold change| >1.5, p
- Published
- 2015
32. Extrafollicular Activation of Lymph Node B Cells by Antigen-Bearing Dendritic Cells
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Hai Qi, Jackson G. Egen, Alex Yee-Chen Huang, and Ronald N. Germain
- Subjects
T-Lymphocytes ,B-cell receptor ,Antigen presentation ,Naive B cell ,Receptors, Antigen, B-Cell ,Mice, Transgenic ,Biology ,Lymphocyte Activation ,Mice ,Cell Movement ,Lymph node stromal cell ,Animals ,Calcium Signaling ,Antigens ,Antigen-presenting cell ,Cell Shape ,B-Lymphocytes ,Multidisciplinary ,Follicular dendritic cells ,Dendritic Cells ,Dendritic cell ,Coculture Techniques ,Endocytosis ,Cell biology ,Mice, Inbred C57BL ,B-1 cell ,Immunology ,Calcium ,Muramidase ,Lymph Nodes - Abstract
In contrast to naïve T cells that recognize short antigen-derived peptides displayed by specialized antigen-presenting cells, immunoglobulin receptors of B lymphocytes primarily recognize intact proteins. How and where within a lymph node such unprocessed antigens become available for naïve B cell recognition is not clear. We used two-photon intravital imaging to show that, after exiting high-endothelial venules and before entry into lymph node follicles, B cells survey locally concentrated dendritic cells. Engagement of the B cell receptor by the dendritic cell (DC)–associated antigen leads to lymphocyte calcium signaling, migration arrest, antigen acquisition, and extrafollicular accumulation. These findings suggest a possible role for antigen-specific B-DC interactions in promoting T cell–dependent antibody responses in vivo.
- Published
- 2006
33. Cytotoxic T Lymphocyte Antigen-4 Accumulation in the Immunological Synapse Is Regulated by TCR Signal Strength
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James P. Allison and Jackson G. Egen
- Subjects
Cell signaling ,Immunoconjugates ,T-Lymphocytes ,T cell ,Molecular Sequence Data ,Immunology ,Receptors, Antigen, T-Cell ,Antigen-Presenting Cells ,Mice, Transgenic ,chemical and pharmacologic phenomena ,Cell Communication ,Biology ,Lymphocyte Activation ,Immunological synapse ,Abatacept ,Mice ,CD28 Antigens ,Antigens, CD ,medicine ,Animals ,Immunology and Allergy ,Cytotoxic T cell ,CTLA-4 Antigen ,Amino Acid Sequence ,Antigen-presenting cell ,Cells, Cultured ,T-cell receptor ,CD28 ,Biological Transport ,hemic and immune systems ,Antigens, Differentiation ,Cell biology ,Infectious Diseases ,medicine.anatomical_structure ,Synapses ,Interleukin-2 ,Intracellular - Abstract
CD28 and CTLA-4 engagement with B7 expressed by APCs generates critical regulatory signals for T cell activation. CD28 is expressed on the T cell surface and enhances T cell expansion, while CTLA-4 localizes primarily to an intracellular compartment and inhibits T cell proliferation. We demonstrate that CTLA-4 has several unique trafficking properties that may regulate its ability to attenuate a T cell response. Importantly, accumulation of CTLA-4 at the immunological synapse is proportional to the strength of the TCR signal, suggesting that cells receiving stronger stimuli are more susceptible to CTLA-4-mediated inhibition. This may represent a novel feedback control mechanism in which a stimulatory signal regulates the recruitment of an inhibitory receptor to a functionally relevant site on the cell surface.
- Published
- 2002
34. Functional consequences of the macrophage stimulating protein 689C inflammatory bowel disease risk allele
- Author
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Jeff Lutman, Henry R. Maun, Elaine Mai, Susan M. Sa, Navneet Ratti, Mary E. Keir, Elsa N N'Diaye, Jackson G. Egen, Eric Stefanich, Steven E. Kauder, Amitabha Chaudhuri, Elizabeth Luis, Lydia Santell, William A. Faubion, Judy Young, Robert A. Lazarus, Lino C. Gonzalez, Robert R. Graham, Lilyan Wright, and Lauri Diehl
- Subjects
Models, Molecular ,Protein Conformation ,lcsh:Medicine ,Inflammation ,Inflammatory bowel disease ,Receptor tyrosine kinase ,Pathogenesis ,Mice ,Polymorphism (computer science) ,Proto-Oncogene Proteins ,parasitic diseases ,medicine ,Genetic predisposition ,Animals ,Humans ,Genetic Predisposition to Disease ,lcsh:Science ,Alleles ,Multidisciplinary ,Polymorphism, Genetic ,biology ,Hepatocyte Growth Factor ,lcsh:R ,Receptor Protein-Tyrosine Kinases ,Epithelial Cells ,3T3 Cells ,medicine.disease ,Inflammatory Bowel Diseases ,Intestines ,Gene Expression Regulation ,Immunology ,Proteolysis ,biology.protein ,Hepatocyte growth factor ,lcsh:Q ,Signal transduction ,medicine.symptom ,medicine.drug ,Signal Transduction ,Research Article - Abstract
Background Macrophage stimulating protein (MSP) is a serum growth factor that binds to and activates the receptor tyrosine kinase, Recepteur d'Origine Nantais (RON). A non-synonymous coding variant in MSP (689C) has been associated with genetic susceptibility to both Crohn's disease and ulcerative colitis, two major types of inflammatory bowel disease (IBD) characterized by chronic inflammation of the digestive tract. We investigated the consequences of this polymorphism for MSP-RON pathway activity and IBD pathogenesis. Methods RON expression patterns were examined on mouse and human cells and tissues under normal and disease conditions to identify cell types regulated by MSP-RON. Recombinant MSP variants were tested for their ability to bind and stimulate RON and undergo proteolytic activation. MSP concentrations were quantified in the serum of individuals carrying the MSP 689R and 689C alleles. Results In intestinal tissue, RON was primarily expressed by epithelial cells under normal and disease conditions. The 689C polymorphism had no impact on the ability of MSP to bind to or signal through RON. In a cohort of normal individuals and IBD patients, carriers of the 689C polymorphism had lower concentrations of MSP in their serum. Conclusions By reducing the quantities of circulating MSP, the 689C polymorphism, or a variant in linkage disequilibrium with this polymorphism, may impact RON ligand availability and thus receptor activity. Given the known functions of RON in regulating wound healing and our analysis of RON expression patterns in human intestinal tissue, these data suggest that decreased RON activity may impact the efficiency of epithelial repair and thus underlie the increased IBD susceptibility associated with the MSP 689C allele.
- Published
- 2013
35. Abstract 4038: Developmentof a murine tumor immunophenotyping platform to support drug discovery anddevelopment in immuno-oncology
- Author
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Pedro J. Beltran, Jackson G. Egen, Kenneth Ganley, Hong Tan, Stephanie Matyas, Brian Belmontes, James B. Rottman, Sarah A. O’Brien, Kimberly L. Merriam, and Gordon Moody
- Subjects
Cancer Research ,Tumor microenvironment ,Angiogenesis ,T cell ,Cancer ,Gene signature ,Biology ,Acquired immune system ,medicine.disease ,Immune system ,Immunophenotyping ,medicine.anatomical_structure ,Oncology ,Immunology ,medicine - Abstract
Recent clinical data highlights the importance of immune cell localization, phenotype, and gene signature as it correlates to a productive anti-tumor response. Preclinically, multiple syngeneic mouse models have been used to study the effects of immunomodulation and define anti-tumor responses to transplanted “self” tumors. However, while the literature describes distinct aspects of many of these models, there is no comprehensive dataset comparing and contrasting their tumor-immune microenvironments across models. These data are critical for better understanding the role that various immune populations play in the anti-tumor response and interpreting observed changes in tumor clearance following treatment with immunomodulatory agents. We have therefore established a platform that 1) quantitates the types of immune cells within murine tumor models, and 2) describes the location of these cells within the tumor. In parallel to the immunophenotyping efforts we have benchmarked tumor models based on their response to antibodies against T cell checkpoint pathways. We sought to use this immunophenotyping platform to identify specific immune modulation that occurs in syngeneic tumors post depletion of macrophages via CSF1R blockade. Tumor-associated macrophages (TAMs) are believed to help promote tumor survival through suppression of the adaptive immune response and the secretion of growth factors that promote tumor growth and angiogenesis. Therefore depletion of TAMs should lead to T-cell recruitment and bolster the antitumor T-cell response. Here we show that treatment of CT-26 and RENCA syngeneic tumors with a CSF1R antagonist leads to depletion of MHCII+ and F4/80+ expressing cells. Future experiments will seek to understand if CSF1R blockade improves the response to T-cell checkpoint immunotherapies. In summary, the development of a murine tumor immunophenotyping platform has allowed insight and evaluation of immune cells in the tumor microenvironment that can ultimately be leveraged to understand the synergistic effects of immunotherapeutics. Citation Format: Brian Belmontes, Stephanie Matyas, Sarah O’Brien, Hong Tan, Kenneth Ganley, Kimberly Merriam, Jim Rottman, Jackson Egen, Pedro Beltran, Gordon Moody. Developmentof a murine tumor immunophenotyping platform to support drug discovery anddevelopment in immuno-oncology. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4038.
- Published
- 2016
36. Three-dimensional imaging of solvent-cleared organs using 3DISCO
- Author
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Christoph P. Mauch, Hans-Ulrich Dodt, Frank Bradke, Klaus Becker, Caroline Hojer, Jackson G. Egen, Nina Jährling, Ali Ertürk, Morgan Sheng, and Farida Hellal
- Subjects
anatomy & histology [Spinal Cord] ,Green Fluorescent Proteins ,Tissue reconstruction ,Mice, Transgenic ,methods [Microscopy, Fluorescence] ,Biology ,chemistry [Furans] ,tetrahydrofuran ,General Biochemistry, Genetics and Molecular Biology ,analysis [Green Fluorescent Proteins] ,chemistry [Green Fluorescent Proteins] ,blood supply [Brain] ,Mice ,Imaging, Three-Dimensional ,Optical clearing ,Microscopy ,Animals ,ddc:610 ,Furans ,dibenzyl ether ,Tissue clearing ,Microscopy, Confocal ,blood supply [Spinal Cord] ,Phenyl Ethers ,chemistry [Phenyl Ethers] ,Brain ,Histology ,Anatomy ,Structure and function ,Three dimensional imaging ,Microscopy, Fluorescence ,Spinal Cord ,Solvents ,chemistry [Solvents] ,anatomy & histology [Brain] ,methods [Imaging, Three-Dimensional] ,Biomedical engineering ,Clearance ,Half-Life - Abstract
The examination of tissue histology by light microscopy is a fundamental tool for investigating the structure and function of organs under normal and disease states. Many current techniques for tissue sectioning, imaging and analysis are time-consuming, and they present major limitations for 3D tissue reconstruction. The introduction of methods to achieve the optical clearing and subsequent light-sheet laser scanning of entire transparent organs without sectioning represents a major advance in the field. We recently developed a highly reproducible and versatile clearing procedure called 3D imaging of solvent-cleared organs, or 3DISCO, which is applicable to diverse tissues including brain, spinal cord, immune organs and tumors. Here we describe a detailed protocol for performing 3DISCO and present its application to various microscopy techniques, including example results from various mouse tissues. The tissue clearing takes as little as 3 h, and imaging can be completed in ∼45 min. 3DISCO is a powerful technique that offers 3D histological views of tissues in a fraction of the time and labor required to complete standard histology studies.
- Published
- 2012
37. A randomised phase I study of etrolizumab (rhuMAb β7) in moderate to severe ulcerative colitis
- Author
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Stefan Schreiber, Richard N. Fedorak, Mary E. Keir, Daan W. Hommes, Sharon O'Byrne, Meina Tang, Daniel C. Baumgart, Diana Luca, Paul Rutgeerts, John C. Mansfield, Brian Bressler, Andreas Sturm, Dimitri Danilenko, Marna Williams, Xiaohui Wei, Jackson G. Egen, and Jennifer Visich
- Subjects
Male ,Ulcerative ,Gastroenterology ,rhuMAb 7 ,Severity of Illness Index ,immunology ,Monoclonal ,Medicine ,Etrolizumab ,genetics ,Stage (cooking) ,IBD models ,Infusions, Intravenous ,Humanized ,Subcutaneous ,apoptosis ,Antibodies, Monoclonal ,Crohns disease ,Middle Aged ,Colitis ,Ulcerative colitis ,inflammatory bowel disorders ,Phase i study ,Crohn's disease ,Treatment Outcome ,arthritis ,6.1 Pharmaceuticals ,Cohort ,cell cycle ,Female ,Drug ,IBD–genetics ,Intravenous ,pharmacokinetics ,signal transduction ,Biotechnology ,safety ,Adult ,medicine.medical_specialty ,Infusions ,Adolescent ,Injections, Subcutaneous ,Clinical Trials and Supportive Activities ,IBD ,Clinical Sciences ,autoimmune disease ,Placebo ,Antibodies, Monoclonal, Humanized ,Antibodies ,Injections ,Dose-Response Relationship ,Paediatrics and Reproductive Medicine ,Young Adult ,Pharmacokinetics ,Double-Blind Method ,Gastrointestinal Agents ,Clinical Research ,Internal medicine ,Humans ,dendritic cells ,Adverse effect ,ulcerative colitis ,Aged ,Gastroenterology & Hepatology ,Dose-Response Relationship, Drug ,business.industry ,Inflammatory Bowel Disease ,IBD-genetics ,Evaluation of treatments and therapeutic interventions ,rhuMAb β7 ,medicine.disease ,drug development ,cytokines ,Surgery ,antibody targeted therapy ,IBD clinical ,IBD basic research ,integrins ,Colitis, Ulcerative ,Digestive Diseases ,business - Abstract
Objective Etrolizumab (rhuMAb β7, anti-β7, PRO145223) is a humanised monoclonal antibody targeting the β7 subunit of the heterodimeric integrins α4β7 and αEβ7, which are implicated in leucocyte migration and retention in ulcerative colitis (UC). This randomised phase I study evaluated the safety and pharmacology of etrolizumab in patients with moderate to severe UC. Design In the single ascending dose (SAD) stage, etrolizumab (0.3, 1.0, 3.0, 10 mg/kg intravenous, 3.0 mg/kg subcutaneous (SC) or placebo) was administered 4:1 (n=25) in each cohort. In the multiple dose (MD) stage, new patients received monthly etrolizumab (0.5 mg/kg SC (n=4), 1.5 mg/kg SC (n=5), 3.0 mg/kg SC (n=4), 4.0 mg/kg intravenous (n=5)) or placebo (n=5). The pharmacokinetics was studied and Mayo Clinic Score evaluated at baseline, day 29 (SAD), and days 43 and 71 (MD). Results In the SAD stage, there were no dose limiting toxicities, infusion or injection site reactions. Two impaired wound healing serious adverse events occurred in two patients receiving etrolizumab. In the MD stage, there were no dose limiting toxicities, and no infusion or injection site reactions. Headache was the most common adverse event, occurring more often in etrolizumab patients. Antietrolizumab antibodies were detected in two subjects. The duration of β7 receptor full occupancy was dose related. A clinical response was observed in 12/18 patients, and clinical remission in 3/18 patients treated with etrolizumab in the MD stage, compared with 4/5 and 1/5 placebo patients, respectively. Conclusion Etrolizumab is well tolerated in moderate to severe UC. Further investigation is warranted.
- Published
- 2012
38. DOP009 Ulcerative colitis: The αEβ7 integrin is associated with a high frequency of Th17, Th1 and Th17/Th1 CD4 lymphocytes
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Mary E. Keir, G. O'Boyle, John A. Kirby, Lauri Diehl, Deena L. Gibbons, Peter M. Irving, Adrian Hayday, Jackson G. Egen, Jeffrey Eastham-Anderson, John C. Mansfield, Gaik W. Tew, Christopher A. Lamb, D.E.J. Jones, and A.K. Long
- Subjects
biology ,business.industry ,Immunology ,Integrin ,Gastroenterology ,biology.protein ,Medicine ,General Medicine ,business ,medicine.disease ,Ulcerative colitis - Published
- 2014
39. Even neurons are excited by Th17 cells
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Jackson G. Egen and Wenjun Ouyang
- Subjects
Infectious Diseases ,Exacerbation ,Immunity ,business.industry ,Immunology ,Medicine ,Immunology and Allergy ,chemical and pharmacologic phenomena ,Disease ,business ,Autoimmune encephalomyelitis - Abstract
The mechanisms by which T helper 17 (Th17) cells contribute to autoimmune encephalomyelitis are likely diverse and not fully elucidated. In this issue of Immunity, Siffrin et al. (2010) propose that Th17 cells engage in direct interactions with neurons, leading to neuronal dysfunction and exacerbation of disease.
- Published
- 2010
40. Making Friends in Out-of-the- Way Places: How Cells of the Immune System Get Together and How They Conduct Their Business as Revealed by Intravital Imaging
- Author
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Ronald N. Germain, Marc Bajénoff, Flora Castellino, Marcello Chieppa, Jackson G. Egen, Alex Y. C. Huang, Masaru Ishii, Lily Y. Koo, and Hai Qi
- Published
- 2010
41. Computational reconstruction of cell and tissue surfaces for modeling and data analysis
- Author
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Martin Meier-Schellersheim, Jackson G. Egen, Ronald N. Germain, Hai Qi, and Frederick Klauschen
- Subjects
Models, Anatomic ,Computational model ,Basis (linear algebra) ,Chemistry ,Confocal ,Systems biology ,Cells ,Resolution (electron density) ,Computational Biology ,Transduction (psychology) ,Computational biology ,General Biochemistry, Genetics and Molecular Biology ,Article ,Structural biology ,Microscopy, Fluorescence ,Image Processing, Computer-Assisted ,Voronoi diagram ,Biological system - Abstract
We present a method for the computational reconstruction of the 3-D morphology of biological objects, such as cells, cell conjugates or 3-D arrangements of tissue structures, using data from high-resolution microscopy modalities. The method is based on the iterative optimization of Voronoi representations of the spatial structures. The reconstructions of biological surfaces automatically adapt to morphological features of varying complexity with flexible degrees of resolution. We show how 3-D confocal images of single cells can be used to generate numerical representations of cellular membranes that may serve as the basis for realistic, spatially resolved computational models of membrane processes or intracellular signaling. Another example shows how the protocol can be used to reconstruct tissue boundaries from segmented two-photon image data that facilitate the quantitative analysis of lymphocyte migration behavior in relation to microanatomical structures. Processing time is of the order of minutes depending on data features and reconstruction parameters.
- Published
- 2009
42. Quantifying cellular interaction dynamics in 3D fluorescence microscopy data
- Author
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Masaru Ishii, Martin Meier-Schellersheim, Marc Bajénoff, Jackson G. Egen, Frederick Klauschen, Hai Qi, Ronald N. Germain, National Institute of Allergy and Infectious Diseases [Bethesda], National Institutes of Health ( NIH ), Institute of Pathology, Universitätsmedizin Berlin, Lymphocyte Biology Section, Laboratory of Immunology ( NIAID - NIH ), National Institutes of Health, Centre d'Immunologie de Marseille - Luminy ( CIML ), Aix Marseille Université ( AMU ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), National Institute of Allergy and Infectious Diseases [Bethesda] (NIAID-NIH), National Institutes of Health [Bethesda] (NIH), Lymphocyte Biology Section, Laboratory of Immunology (NIAID - NIH), Centre d'Immunologie de Marseille - Luminy (CIML), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Fluorescence-lifetime imaging microscopy ,MESH : Microscopy, Fluorescence ,Systems biology ,Osteoclasts ,MESH: Microscopy, Fluorescence ,Transduction (psychology) ,MESH: Imaging, Three-Dimensional ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Bone and Bones ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Imaging, Three-Dimensional ,MESH: Osteoclasts ,Microscopy ,MESH : Bone and Bones ,MESH : Mice ,Fluorescence microscope ,Animals ,[ SDV.IMM ] Life Sciences [q-bio]/Immunology ,Segmentation ,MESH: Animals ,MESH: Mice ,030304 developmental biology ,0303 health sciences ,MESH: Dendritic Cells ,Dendritic Cells ,MESH: Bone and Bones ,Object detection ,Microscopy, Fluorescence ,MESH : Osteoclasts ,030220 oncology & carcinogenesis ,Temporal resolution ,MESH : Dendritic Cells ,Biophysics ,[SDV.IMM]Life Sciences [q-bio]/Immunology ,MESH : Imaging, Three-Dimensional ,MESH : Animals ,Biological system - Abstract
International audience; The wealth of information available from advanced fluorescence imaging techniques used to analyze biological processes with high spatial and temporal resolution calls for high-throughput image analysis methods. Here, we describe a fully automated approach to analyzing cellular interaction behavior in 3D fluorescence microscopy images. As example application, we present the analysis of drug-induced and S1P(1)-knockout-related changes in bone-osteoclast interactions. Moreover, we apply our approach to images showing the spatial association of dendritic cells with the fibroblastic reticular cell network within lymph nodes and to microscopy data regarding T-B lymphocyte synapse formation. Such analyses that yield important information about the molecular mechanisms determining cellular interaction behavior would be very difficult to perform with approaches that rely on manual/semi-automated analyses. This protocol integrates adaptive threshold segmentation, object detection, adaptive color channel merging, and neighborhood analysis and permits rapid, standardized, quantitative analysis and comparison of the relevant features in large data sets.
- Published
- 2009
43. In vivo imaging reveals an essential role for neutrophils in leishmaniasis transmitted by sand flies
- Author
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Nicola Kimblin, Michael P. Fay, Nágila Francinete Costa Secundino, Shaden Kamhawi, Nathan C. Peters, Jackson G. Egen, David B. Sacks, Alain Debrabant, Ronald N. Germain, and Phillip G. Lawyer
- Subjects
Neutrophils ,Phagocytosis ,Leishmaniasis, Cutaneous ,Apoptosis ,Mice, Transgenic ,Biology ,Host-Parasite Interactions ,Mice ,Cell Movement ,parasitic diseases ,medicine ,Animals ,Leishmania major ,Phlebotomus ,Skin ,Microscopy ,Multidisciplinary ,Obligate ,Macrophages ,Insect Bites and Stings ,Leishmaniasis ,Leishmania ,biology.organism_classification ,medicine.disease ,Flow Cytometry ,Virology ,Insect Vectors ,Mice, Inbred C57BL ,Neutrophil Infiltration ,Vector (epidemiology) ,Intravital microscopy - Abstract
Infection with the obligate intracellular protozoan Leishmania is thought to be initiated by direct parasitization of macrophages, but the early events following transmission to the skin by vector sand flies have been difficult to examine directly. Using dynamic intravital microscopy and flow cytometry, we observed a rapid and sustained neutrophilic infiltrate at localized sand fly bite sites. Invading neutrophils efficiently captured Leishmania major ( L.m. ) parasites early after sand fly transmission or needle inoculation, but phagocytosed L.m. remained viable and infected neutrophils efficiently initiated infection. Furthermore, neutrophil depletion reduced, rather than enhanced, the ability of parasites to establish productive infections. Thus, L.m. appears to have evolved to both evade and exploit the innate host response to sand fly bite in order to establish and promote disease.
- Published
- 2008
44. Making friends in out-of-the-way places: how cells of the immune system get together and how they conduct their business as revealed by intravital imaging
- Author
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Hai Qi, Jackson G. Egen, Flora Castellino, Masaru Ishii, Alex Yee-Chen Huang, Ronald N. Germain, Marcello Chieppa, Lily Koo, Marc Bajénoff, Germain, R. N., Bajenoff, M., Castellino, F., Chieppa, M., Egen, J. G., Huang, A. Y. C., Ishii, M., Koo, L. Y., and Qi, H.
- Subjects
Diagnostic Imaging ,Stromal cell ,Immunology ,Inflammation ,Biology ,Immune system ,Cell trafficking ,medicine ,Immunology and Allergy ,Animals ,Humans ,Antigens ,B cell ,Microscopy ,Animal ,T cell ,Cell migration ,Dendritic cell ,T lymphocyte ,Cell biology ,Haematopoiesis ,Antigen ,Immune System ,In vivo imaging ,medicine.symptom ,Intravital microscopy ,Human - Abstract
A central characteristic of the immune system is the constantly changing location of most of its constituent cells. Lymphoid and myeloid cells circulate in the blood, and subsets of these cells enter, move, and interact within, then leave organized lymphoid tissues. When inflammation is present, various hematopoietic cells also exit the vasculature and migrate within non-lymphoid tissues, where they carry out effector functions that support host defense or result in autoimmune pathology. Effective innate and adaptive immune responses involve not only the action of these individual cells but also productive communication among them, often requiring direct membrane contact between rare antigen-specific or antigen-bearing cells. Here, we describe our ongoing studies using two-photon intravital microscopy to probe the in situ behavior of the cells of the immune system and their interactions with non-hematopoietic stromal elements. We emphasize the importance of non-random cell migration within lymphoid tissues and detail newly established mechanisms of traffic control that operate at multiple organizational scales to facilitate critical cell contacts. We also describe how the methods we have developed for imaging within lymphoid sites are being applied to other tissues and organs, revealing dynamic details of host-pathogen interactions previously inaccessible to direct observation. © 2008 The Authors.
- Published
- 2008
45. Highways, byways and breadcrumbs: directing lymphocyte traffic in the lymph node
- Author
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Jackson G. Egen, Marc Bajénoff, Alex Yee-Chen Huang, Ronald N. Germain, Flora Castellino, and Hai Qi
- Subjects
Cell signaling ,Lymphocyte ,Immunology ,Cell movement ,Cell Communication ,Dendritic Cells ,Biology ,Random migration ,medicine.anatomical_structure ,Immune system ,Lymphatic system ,Antigen ,Cell Movement ,medicine ,Immunology and Allergy ,Animals ,Humans ,Lymph Nodes ,Lymphocytes ,Lymph node - Abstract
The lymph node (LN) is charged with a crucial function in the mammalian immune system: to facilitate physical interactions between extremely rare cells arriving from different tissue compartments. Paramount to carrying out this function is its unique placement at the interface between the blood and lymphatic systems, thus enabling tissue-derived antigen and antigen-presenting cells, especially dendritic cells (DCs) to gather in close proximity to blood-derived antigen-specific motile lymphocytes. A generally held view is that this accumulation of cells, coupled with stochastic migration, is itself sufficient to facilitate a physiologically adequate frequency of cell-cell contacts due to random migration within the confined space of the LN. Based on recent data, we propose an expanded model of LN function in which unique architectural features and chemical signals together provide a means of enhancing otherwise unlikely encounters between sparse DCs and rare antigen-specific lymphocytes.
- Published
- 2007
46. Sa1145 AlphaE (αE) Integrin Protein and Gene Expression Are Augmented in the Ileum Relative to the Colon in Crohn's Disease
- Author
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Jeffrey Eastham-Anderson, Alexis Scherl, John A. Kirby, Jackson G. Egen, William A. Faubion, Christopher A. Lamb, John C. Mansfield, Ryan Ichikawa, Sharon O'Byrne, Wei Tew, and Mary E. Keir
- Subjects
Crohn's disease ,Hepatology ,biology ,business.industry ,Integrin ,Gastroenterology ,Ileum ,medicine.disease ,medicine.anatomical_structure ,Immunology ,Gene expression ,biology.protein ,Medicine ,business - Published
- 2015
47. Stromal cell networks regulate lymphocyte entry, migration, and territoriality in lymph nodes
- Author
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Ronald N. Germain, Frédéric Brau, Nicolas Glaichenhaus, Jackson G. Egen, Lily Koo, Marc Bajénoff, Jean Pierre Laugier, Lymphocyte Biology Section ( NIAID ), National Institutes of Health, Immunologie des Maladies Infectieuses Allergiques et Autoimmunes, Université Nice Sophia Antipolis ( UNS ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ), Centre Commun de Microscopie Appliquée ( CCMA ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ), Institut de pharmacologie moléculaire et cellulaire ( IPMC ), Université Côte d'Azur ( UCA ) -Université Côte d'Azur ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Intramural Research Program of NIAID, NIH, DHHS, Institut de la Santé et de la Recherche Médicale (INSERM), Lymphocyte Biology Section (NIAID), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Commun de Microscopie Appliquée (CCMA), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Institut de pharmacologie moléculaire et cellulaire (IPMC), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Pathology ,Adoptive cell transfer ,Lymphocyte ,MESH : Immunohistochemistry ,MESH : Diagnostic Imaging ,MESH : Lymphocytes ,MESH: Chemotaxis, Leukocyte ,MESH: Lymph Nodes ,Cell Communication ,Mice ,0302 clinical medicine ,Reticular cell ,MESH: Microscopy, Confocal ,Immunology and Allergy ,[ SDV.IMM ] Life Sciences [q-bio]/Immunology ,MESH: Animals ,Lymphocytes ,MESH : Lymph Nodes ,0303 health sciences ,Microscopy, Confocal ,MESH : Adoptive Transfer ,Cell migration ,MESH : Chemotaxis, Leukocyte ,Adoptive Transfer ,Immunohistochemistry ,Cell biology ,Chemotaxis, Leukocyte ,medicine.anatomical_structure ,Infectious Diseases ,MESH : Microscopy, Electron, Transmission ,MESH: Microscopy, Electron, Transmission ,[SDV.IMM]Life Sciences [q-bio]/Immunology ,Diagnostic Imaging ,MESH : Microscopy, Electron, Scanning ,medicine.medical_specialty ,Stromal cell ,Naive T cell ,MESH: Microscopy, Electron, Scanning ,MESH : Cell Communication ,T cell ,Immunology ,MESH : Mice, Inbred C57BL ,Biology ,03 medical and health sciences ,Microscopy, Electron, Transmission ,MESH: Mice, Inbred C57BL ,MESH: Cell Communication ,MESH : Mice ,medicine ,Animals ,MESH : Microscopy, Confocal ,MESH: Mice ,030304 developmental biology ,Follicular dendritic cells ,MESH: Diagnostic Imaging ,MESH: Immunohistochemistry ,Mice, Inbred C57BL ,MESH: Adoptive Transfer ,CELLIMMUNO ,MESH : Stromal Cells ,Microscopy, Electron, Scanning ,CELLBIO ,MESH: Lymphocytes ,Lymph Nodes ,MESH : Animals ,Stromal Cells ,MESH: Stromal Cells ,030215 immunology - Abstract
SummaryAfter entry into lymph nodes (LNs), B cells migrate to follicles, whereas T cells remain in the paracortex, with each lymphocyte type showing apparently random migration within these distinct areas. Other than chemokines, the factors contributing to this spatial segregation and to the observed patterns of lymphocyte movement are poorly characterized. By combining confocal, electron, and intravital microscopy, we showed that the fibroblastic reticular cell network regulated naive T cell access to the paracortex and also supported and defined the limits of T cell movement within this domain, whereas a distinct follicular dendritic cell network similarly served as the substratum for movement of follicular B cells. These results highlight the central role of stromal microanatomy in orchestrating cell migration within the LN.
- Published
- 2006
48. P23 Target And Biomarker Discovery For Hedgehog Pathway Activity In Idiopathic Pulmonary Fibrosis In Support Of A Phase 2 Randomised, Double-blind, Placebo-controlled Study To Assess Efficacy And Safety Of Vismodegib In Ipf (island)
- Author
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Murat Yaylaoglu, Elsa N N'Diaye, Guiquan Jia, Toby M. Maher, J Kaminski, Jackson G. Egen, AlexanderR Abbas, Joseph R. Arron, A Scalori, Daryle Depianto, J Hou, Harold R. Collard, Paul J. Wolters, Sanjay Chandriani, and A Ackrill
- Subjects
Pulmonary and Respiratory Medicine ,Oncology ,medicine.medical_specialty ,biology ,business.industry ,Interstitial lung disease ,Vismodegib ,respiratory system ,medicine.disease ,Hedgehog signaling pathway ,respiratory tract diseases ,Idiopathic pulmonary fibrosis ,GLI1 ,Internal medicine ,GLI2 ,Immunology ,medicine ,biology.protein ,Biomarker (medicine) ,Basal cell carcinoma ,business ,medicine.drug - Abstract
Objectives Idiopathic pulmonary fibrosis (IPF) is associated with aberrant expression of signalling pathways involved in embryonic development, including the Hedgehog (Hh) pathway. Hh can promote multiple profibrotic processes including myofibroblast differentiation, expression of extracellular matrix genes, migration, and survival. Vismodegib is a small-molecule inhibitor of the Hedgehog (Hh) signalling pathway approved for the treatment of basal cell carcinoma. We sought to evaluate the activity of Hh signalling in IPF lung tissue and identify blood biomarkers of Hh pathway activity in IPF patients. Methods Gene expression in biopsies from IPF and control unused donor lungs, and in fibroblasts stimulated with Shh in vitro . CXCL14 protein was measured in plasma from IPF patients and from solid tumour patients treated with vismodegib in a phase 1b clinical trial (NCT00968981). Results We observed significantly increased expression levels of Hh pathway genes including SMO, PTCH2, GLI1, and GLI2 in IPF vs control lungs. To identify candidate systemic biomarkers of Hh pathway activity, we compared transcriptional data from IPF lung biopsies and fibroblasts stimulated in vitro with Shh. The gene most significantly upregulated in both datasets was CXCL14, which encodes a soluble secreted chemokine whose expression is inhibited in vitro by the addition of vismodegib. Circulating CXCL14 protein levels were significantly higher in plasma from IPF patients than controls. In solid tumour patients, circulating CXCL14 levels were significantly reduced upon treatment with vismodegib. Conclusions We observed strong evidence for Hedgehog pathway activity in IPF lungs. CXCL14 is a systemic biomarker that could be used to identify IPF patients with increased Hh pathway activity and monitor the pharmacodynamic effects of vismodegib in IPF. The ISLAND trial is a phase 2 randomised, double-blind, placebo-controlled study designed to evaluate the safety and efficacy of vismodegib in IPF patients. ISLAND will enrol 129 patients with IPF, randomised 2:1 to vismodegib or placebo for 60 weeks. The primary efficacy objective is to evaluate the effect of vismodegib on mean change in forced vital capacity (FVC). Secondary outcome measures include IPF and/or Hh-associated biomarkers, progression-free survival, and change in quantitative lung fibrosis on HRCT. Enrollment is expected to start in October 2014.
- Published
- 2014
49. An extended vision for dynamic high-resolution intravital immune imaging
- Author
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Hai Qi, Flora Castellino, Lily Koo, Jackson G. Egen, Marcello Chieppa, Alex Yee-Chen Huang, Ronald N. Germain, Germain, R. N., Castellino, F., Chieppa, M., Egen, J. G., Huang, A. Y. C., Koo, L. Y., and Qi, H.
- Subjects
Cell type ,Stromal cell ,T cell ,Immunology ,Biology ,Article ,Immune system ,medicine ,Immunology and Allergy ,Animals ,Humans ,Antigen-presenting cell ,Lymph node ,Microscopy ,Antigen presenting cell ,Microscopy, Confocal ,Microscopy, Video ,Animal ,Dendritic cell ,Natural killer T cell ,Cell biology ,medicine.anatomical_structure ,Microscopy, Fluorescence, Multiphoton ,Chemokine ,Immune System ,Human ,Forecasting - Abstract
The past few years have seen the application of confocal and especially two-photon microscopy to the dynamic high-resolution imaging of lymphocytes and antigen presenting cells within organs such as lymph nodes and thymus. After summarizing some of the published results obtained to date using these methods, we describe our view of how this technology will develop and be applied in the near future. This includes its extension to a wide variety of non-lymphoid tissues, to the tracking of functional responses in addition to migratory behavior, to the analysis of molecular events previously studied only in vitro, to dissection of the interplay between hematopoietic and stromal elements, to visualization of a wider array of cell types including neutrophils, macrophages, NK cells, NKT cells and others, and to the interaction of the host with infectious agents. Reaching these goals will depend on a combination of new tools for genetic manipulations, novel fluorescent reporters, enhanced instrumentation, and better surgical techniques for the extended imaging of live animals. The end result will be a new level of understanding of how orchestrated cell movement and interaction contribute to the physiological and pathological activities of the immune system.
- Published
- 2005
50. Protein Localization in Negative Signaling
- Author
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James P. Allison and Jackson G. Egen
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Downregulation and upregulation ,Kinase ,food and beverages ,Stimulation ,Biology ,Signal transduction ,Ligand (biochemistry) ,Inhibitory postsynaptic potential ,Receptor ,Transforming growth factor ,Cell biology - Abstract
Cellular activation is regulated by the integration of both positive and negative signals. While positive signaling can be simplistically thought of as the initiation of a biochemical pathway leading to activation of a cellular process, negative signaling can have multiple meanings. From the standpoint of a cellular process such as proliferation or protein secretion, the initiation of any pathway that functions to downregulate these events can be defined as negative signaling. For instance, transforming growth factor β (TGFβ) receptor can transduce a negative signal by upregulating cyclin-dependent kinase inhibitory proteins (CKIs) leading to cell cycle arrest. Negative signaling can also refer to the activation of specific pathways that inhibit cellular stimulation, such as the inhibitory function of the glycine and γ-aminobutyric acid (GABA) receptors in neurons. Upon binding to their respective ligand, these receptors undergo a conformational change that allows the entry of chloride ions into the cell, thereby generating a hyperpolarizing inhibitory signal. The signals generated in the above examples have inhibitory consequences for cellular activation; however, the intricacies of these processes can be thought of as being similar to those of positive signaling. In both cases, specific signaling pathways are activated but with differing downstream effects. This chapter focuses on a distinct form of negative signaling in which extrinsic cell signals serve to directly antagonize positive signals.
- Published
- 2003
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