58 results on '"Corcoran LM"'
Search Results
2. Two of a kind: transmissible Schwann cell cancers in the endangered Tasmanian devil (Sarcophilus harrisii).
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Patchett AL, Coorens THH, Darby J, Wilson R, McKay MJ, Kamath KS, Rubin A, Wakefield M, Mcintosh L, Mangiola S, Pye RJ, Flies AS, Corcoran LM, Lyons AB, Woods GM, Murchison EP, Papenfuss AT, and Tovar C
- Subjects
- Animals, Biomarkers, Tumor genetics, Facial Neoplasms genetics, Facial Neoplasms metabolism, Facial Neoplasms pathology, Humans, Schwann Cells metabolism, Biomarkers, Tumor metabolism, Facial Neoplasms veterinary, Marsupialia physiology, Proteome analysis, Schwann Cells pathology, Transcriptome
- Abstract
Devil facial tumour disease (DFTD) comprises two genetically distinct transmissible cancers (DFT1 and DFT2) endangering the survival of the Tasmanian devil (Sarcophilus harrisii) in the wild. DFT1 first arose from a cell of the Schwann cell lineage; however, the tissue-of-origin of the recently discovered DFT2 cancer is unknown. In this study, we compared the transcriptome and proteome of DFT2 tumours to DFT1 and normal Tasmanian devil tissues to determine the tissue-of-origin of the DFT2 cancer. Our findings demonstrate that DFT2 expresses a range of Schwann cell markers and exhibits expression patterns consistent with a similar origin to the DFT1 cancer. Furthermore, DFT2 cells express genes associated with the repair response to peripheral nerve damage. These findings suggest that devils may be predisposed to transmissible cancers of Schwann cell origin. The combined effect of factors such as frequent nerve damage from biting, Schwann cell plasticity and low genetic diversity may allow these cancers to develop on rare occasions. The emergence of two independent transmissible cancers from the same tissue in the Tasmanian devil presents an unprecedented opportunity to gain insight into cancer development, evolution and immune evasion in mammalian species.
- Published
- 2020
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3. Pou2f2 Regulates the Distribution of Dorsal Interneurons in the Mouse Developing Spinal Cord.
- Author
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Masgutova G, Harris A, Jacob B, Corcoran LM, and Clotman F
- Abstract
Spinal dorsal interneurons, which are generated during embryonic development, relay and process sensory inputs from the periphery to the central nervous system. Proper integration of these cells into neuronal circuitry depends on their correct positioning within the spinal parenchyma. Molecular cues that control neuronal migration have been extensively characterized but the genetic programs that regulate their production remain poorly investigated. Onecut (OC) transcription factors have been shown to control the migration of the dorsal interneurons (dINs) during spinal cord development. Here, we report that the OC factors moderate the expression of Pou2f2 , a transcription factor essential for B-cell differentiation, in spinal dINs. Overexpression or inactivation of Pou2f2 leads to alterations in the differentiation of dI2, dI3 and Phox2a-positive dI5 populations and to defects in the distribution of dI2-dI6 interneurons. Thus, an OC-Pou2f2 genetic cascade regulates adequate diversification and distribution of dINs during embryonic development., (Copyright © 2019 Masgutova, Harris, Jacob, Corcoran and Clotman.)
- Published
- 2019
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4. Class-Switch Recombination Occurs Infrequently in Germinal Centers.
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Roco JA, Mesin L, Binder SC, Nefzger C, Gonzalez-Figueroa P, Canete PF, Ellyard J, Shen Q, Robert PA, Cappello J, Vohra H, Zhang Y, Nowosad CR, Schiepers A, Corcoran LM, Toellner KM, Polo JM, Meyer-Hermann M, Victora GD, and Vinuesa CG
- Subjects
- Animals, Cell Differentiation, Cells, Cultured, Humans, Mice, Mice, Inbred C57BL, Phylogeny, Receptors, Antigen, B-Cell metabolism, B-Lymphocytes immunology, Germinal Center immunology, Immunoglobulin Class Switching, Plasma Cells immunology, Plasmablastic Lymphoma immunology, T-Lymphocytes, Helper-Inducer immunology
- Abstract
Class-switch recombination (CSR) is a DNA recombination process that replaces the immunoglobulin (Ig) constant region for the isotype that can best protect against the pathogen. Dysregulation of CSR can cause self-reactive BCRs and B cell lymphomas; understanding the timing and location of CSR is therefore important. Although CSR commences upon T cell priming, it is generally considered a hallmark of germinal centers (GCs). Here, we have used multiple approaches to show that CSR is triggered prior to differentiation into GC B cells or plasmablasts and is greatly diminished in GCs. Despite finding a small percentage of GC B cells expressing germline transcripts, phylogenetic trees of GC BCRs from secondary lymphoid organs revealed that the vast majority of CSR events occurred prior to the onset of somatic hypermutation. As such, we have demonstrated the existence of IgM-dominated GCs, which are unlikely to occur under the assumption of ongoing switching., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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5. Onecut Factors and Pou2f2 Regulate the Distribution of V2 Interneurons in the Mouse Developing Spinal Cord.
- Author
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Harris A, Masgutova G, Collin A, Toch M, Hidalgo-Figueroa M, Jacob B, Corcoran LM, Francius C, and Clotman F
- Abstract
Acquisition of proper neuronal identity and position is critical for the formation of neural circuits. In the embryonic spinal cord, cardinal populations of interneurons diversify into specialized subsets and migrate to defined locations within the spinal parenchyma. However, the factors that control interneuron diversification and migration remain poorly characterized. Here, we show that the Onecut transcription factors are necessary for proper diversification and distribution of the V2 interneurons in the developing spinal cord. Furthermore, we uncover that these proteins restrict and moderate the expression of spinal isoforms of Pou2f2 , a transcription factor known to regulate B-cell differentiation. By gain- or loss-of-function experiments, we show that Pou2f2 contribute to regulate the position of V2 populations in the developing spinal cord. Thus, we uncovered a genetic pathway that regulates the diversification and the distribution of V2 interneurons during embryonic development.
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- 2019
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6. Transcription Factor PU.1 Promotes Conventional Dendritic Cell Identity and Function via Induction of Transcriptional Regulator DC-SCRIPT.
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Chopin M, Lun AT, Zhan Y, Schreuder J, Coughlan H, D'Amico A, Mielke LA, Almeida FF, Kueh AJ, Dickins RA, Belz GT, Naik SH, Lew AM, Bouillet P, Herold MJ, Smyth GK, Corcoran LM, and Nutt SL
- Subjects
- Animals, Antigen Presentation, Cell Differentiation, Cell Lineage, DNA-Binding Proteins genetics, Gene Expression Regulation, HEK293 Cells, Humans, Interferon Type I metabolism, Mice, Mice, Transgenic, Nuclear Proteins genetics, Proto-Oncogene Proteins genetics, Signal Transduction, Trans-Activators genetics, Transcription Factors genetics, Transcriptome, DNA-Binding Proteins metabolism, Dendritic Cells physiology, Nuclear Proteins metabolism, Proto-Oncogene Proteins metabolism, Trans-Activators metabolism, Transcription Factors metabolism
- Abstract
Dendritic cells (DCs) are can be broadly divided into conventional (cDC) and plasmacytoid (pDC) subsets. Despite the importance of this lineage diversity, its genetic basis is not fully understood. We found that conditional ablation of the Ets-family transcription factor PU.1 in DC-restricted progenitors led to increased pDC production at the expense of cDCs. PU.1 controlled many of the cardinal functions of DCs, such as antigen presentation by cDCs and type I interferon production by pDCs. Conditional ablation of PU.1 de-repressed the pDC transcriptional signature in cDCs. The combination of genome-wide mapping of PU.1 binding and gene expression analysis revealed a key role for PU.1 in maintaining cDC identity through the induction of the transcriptional regulator DC-SCRIPT. PU.1 activated DC-SCRIPT expression, which in turn promoted cDC formation, particularly of cDC1s, and repressed pDC development. Thus, cDC identity is regulated by a transcriptional node requiring PU.1 and DC-SCRIPT., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2019
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7. Haemopedia RNA-seq: a database of gene expression during haematopoiesis in mice and humans.
- Author
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Choi J, Baldwin TM, Wong M, Bolden JE, Fairfax KA, Lucas EC, Cole R, Biben C, Morgan C, Ramsay KA, Ng AP, Kauppi M, Corcoran LM, Shi W, Wilson N, Wilson MJ, Alexander WS, Hilton DJ, and de Graaf CA
- Subjects
- Animals, Computational Biology, Hematopoietic Stem Cells metabolism, High-Throughput Nucleotide Sequencing trends, Humans, Mice, RNA-Seq, Software, Databases, Genetic, Gene Expression genetics, Hematopoiesis genetics, Transcriptome genetics
- Abstract
During haematopoiesis, haematopoietic stem cells differentiate into restricted potential progenitors before maturing into the many lineages required for oxygen transport, wound healing and immune response. We have updated Haemopedia, a database of gene-expression profiles from a broad spectrum of haematopoietic cells, to include RNA-seq gene-expression data from both mice and humans. The Haemopedia RNA-seq data set covers a wide range of lineages and progenitors, with 57 mouse blood cell types (flow sorted populations from healthy mice) and 12 human blood cell types. This data set has been made accessible for exploration and analysis, to researchers and clinicians with limited bioinformatics experience, on our online portal Haemosphere: https://www.haemosphere.org. Haemosphere also includes nine other publicly available high-quality data sets relevant to haematopoiesis. We have added the ability to compare gene expression across data sets and species by curating data sets with shared lineage designations or to view expression gene vs gene, with all plots available for download by the user.
- Published
- 2019
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8. Germline-activating mutations in PIK3CD compromise B cell development and function.
- Author
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Avery DT, Kane A, Nguyen T, Lau A, Nguyen A, Lenthall H, Payne K, Shi W, Brigden H, French E, Bier J, Hermes JR, Zahra D, Sewell WA, Butt D, Elliott M, Boztug K, Meyts I, Choo S, Hsu P, Wong M, Berglund LJ, Gray P, O'Sullivan M, Cole T, Holland SM, Ma CS, Burkhart C, Corcoran LM, Phan TG, Brink R, Uzel G, Deenick EK, and Tangye SG
- Subjects
- Animals, Antibody Affinity immunology, Bone Marrow Cells cytology, Cell Differentiation, Cell Proliferation, Child, Gain of Function Mutation genetics, Humans, Immunoglobulin Class Switching, Immunoglobulins metabolism, Interleukins pharmacology, Mice, Models, Animal, Phenotype, Phosphatidylinositol 3-Kinases metabolism, Plasma Cells metabolism, Signal Transduction, B-Lymphocytes cytology, B-Lymphocytes immunology, Class I Phosphatidylinositol 3-Kinases genetics, Germ-Line Mutation genetics, Phosphatidylinositol 3-Kinases genetics
- Abstract
Gain-of-function (GOF) mutations in PIK3CD , encoding the p110δ subunit of phosphatidylinositide 3-kinase (PI3K), cause a primary immunodeficiency. Affected individuals display impaired humoral immune responses following infection or immunization. To establish mechanisms underlying these immune defects, we studied a large cohort of patients with PIK3CD GOF mutations and established a novel mouse model using CRISPR/Cas9-mediated gene editing to introduce a common pathogenic mutation in Pik3cd In both species, hyperactive PI3K severely affected B cell development and differentiation in the bone marrow and the periphery. Furthermore, PI3K GOF B cells exhibited intrinsic defects in class-switch recombination (CSR) due to impaired induction of activation-induced cytidine deaminase (AID) and failure to acquire a plasmablast gene signature and phenotype. Importantly, defects in CSR, AID expression, and Ig secretion were restored by leniolisib, a specific p110δ inhibitor. Our findings reveal key roles for balanced PI3K signaling in B cell development and long-lived humoral immunity and memory and establish the validity of treating affected individuals with p110δ inhibitors., (© 2018 Avery et al.)
- Published
- 2018
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9. Mining the Plasma Cell Transcriptome for Novel Cell Surface Proteins.
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Trezise S, Karnowski A, Fedele PL, Mithraprabhu S, Liao Y, D'Costa K, Kueh AJ, Hardy MP, Owczarek CM, Herold MJ, Spencer A, Shi W, Willis SN, Nutt SL, and Corcoran LM
- Subjects
- Animals, B-Lymphocytes immunology, Bone Marrow Cells cytology, Bone Marrow Cells immunology, Cell Line, Tumor, Humans, Immunity, Humoral, Membrane Proteins physiology, Mice, Mice, Inbred C57BL, Mice, Knockout, Multiple Myeloma genetics, Mutation, Neoplasm Proteins physiology, Phosphatidate Phosphatase physiology, Plasma Cells cytology, Primary Cell Culture, Antibody-Producing Cells immunology, Membrane Proteins genetics, Multiple Myeloma immunology, Neoplasm Proteins genetics, Phosphatidate Phosphatase genetics, Plasma Cells immunology, Transcriptome
- Abstract
Antibody Secreting Cells (ASCs) are a fundamental component of humoral immunity, however, deregulated or excessive antibody production contributes to the pathology of autoimmune diseases, while transformation of ASCs results in the malignancy Multiple Myeloma (MM). Despite substantial recent improvements in treating these conditions, there is as yet no widely used ASC-specific therapeutic approach, highlighting a critical need to identify novel methods of targeting normal and malignant ASCs. Surface molecules specifically expressed by the target cell population represent ideal candidates for a monoclonal antibody-based therapy. By interrogating the ASC gene signature that we previously defined we identified three surface proteins, Plpp5, Clptm1l and Itm2c, which represent potential targets for novel MM treatments. Plpp5 , Clptm1l and Itm2c are highly and selectively expressed by mouse and human ASCs as well as MM cells. To investigate the function of these proteins within the humoral immune system we have generated three novel mouse strains, each carrying a loss-of-function mutation in either Plpp5 , Clptm1l or Itm2c . Through analysis of these novel strains, we have shown that Plpp5, Clptm1l and Itm2c are dispensable for the development, maturation and differentiation of B-lymphocytes, and for the production of antibodies by ASCs. As adult mice lacking either protein showed no apparent disease phenotypes, it is likely that targeting these molecules on ASCs will have minimal on-target adverse effects.
- Published
- 2018
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10. Transcriptome and proteome profiling reveals stress-induced expression signatures of imiquimod-treated Tasmanian devil facial tumor disease (DFTD) cells.
- Author
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Patchett AL, Wilson R, Charlesworth JC, Corcoran LM, Papenfuss AT, Lyons BA, Woods GM, and Tovar C
- Abstract
As a topical cancer immunotherapy, the toll-like receptor 7 ligand imiquimod activates tumor regression via stimulation of immune cell infiltration and cytotoxic responses. Imiquimod also exerts direct pro-apoptotic effects on tumor cells in vitro , but a role for these effects in imiquimod-induced tumor regression remains undefined. We previously demonstrated that cell lines derived from devil facial tumor disease (DFTD), a transmissible cancer threatening the survival of the Tasmanian devil ( Sarcophilus harrisii ), are sensitive to imiquimod-induced apoptosis. In this study, the pro-apoptotic effects of imiquimod in DFTD have been investigated using RNA-sequencing and label-free quantitative proteomics. This analysis revealed that changes to gene and protein expression in imiquimod treated DFTD cells are consistent with the onset of oxidative and endoplasmic reticulum stress responses, and subsequent activation of the unfolded protein response, autophagy, cell cycle arrest and apoptosis. Imiquimod also regulates the expression of oncogenic pathways, providing a direct mechanism by which this drug may increase tumor susceptibility to immune cytotoxicity in vivo . Our study has provided the first global analysis of imiquimod-induced effects in any tumor cell line. These findings have highlighted the potential of cell stress pathways as therapeutic targets in DFTD, and will allow for improved mechanistic use of imiquimod as a therapy in both the Tasmanian devil and human cancers., Competing Interests: CONFLICTS OF INTEREST The authors declare no potential conflicts of interest.
- Published
- 2018
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11. Immunization Strategies Producing a Humoral IgG Immune Response against Devil Facial Tumor Disease in the Majority of Tasmanian Devils Destined for Wild Release.
- Author
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Pye R, Patchett A, McLennan E, Thomson R, Carver S, Fox S, Pemberton D, Kreiss A, Baz Morelli A, Silva A, Pearse MJ, Corcoran LM, Belov K, Hogg CJ, Woods GM, and Lyons AB
- Subjects
- Animals, Carboxymethylcellulose Sodium analogs & derivatives, Female, Histocompatibility Antigens Class I genetics, Histocompatibility Antigens Class I metabolism, Imiquimod immunology, Immunity, Humoral, Immunization, Secondary, Immunoglobulin G blood, Male, Poly I-C immunology, Polylysine analogs & derivatives, Polylysine immunology, Tumor Escape, Adjuvants, Immunologic, Cancer Vaccines immunology, Facial Neoplasms immunology, Immunotherapy methods, Marsupialia immunology
- Abstract
Devil facial tumor disease (DFTD) is renowned for its successful evasion of the host immune system. Down regulation of the major histocompatabilty complex class I molecule (MHC-I) on the DFTD cells is a primary mechanism of immune escape. Immunization trials on captive Tasmanian devils have previously demonstrated that an immune response against DFTD can be induced, and that immune-mediated tumor regression can occur. However, these trials were limited by their small sample sizes. Here, we describe the results of two DFTD immunization trials on cohorts of devils prior to their wild release as part of the Tasmanian Government's Wild Devil Recovery project. 95% of the devils developed anti-DFTD antibody responses. Given the relatively large sample sizes of the trials ( N = 19 and N = 33), these responses are likely to reflect those of the general devil population. DFTD cells manipulated to express MHC-I were used as the antigenic basis of the immunizations in both trials. Although the adjuvant composition and number of immunizations differed between trials, similar anti-DFTD antibody levels were obtained. The first trial comprised DFTD cells and the adjuvant combination of ISCOMATRIX™, polyIC, and CpG with up to four immunizations given at monthly intervals. This compared to the second trial whereby two immunizations comprising DFTD cells and the adjuvant combination ISCOMATRIX™, polyICLC (Hiltonol
® ) and imiquimod were given a month apart, providing a shorter and, therefore, more practical protocol. Both trials incorporated a booster immunization given up to 5 months after the primary course. A key finding was that devils in the second trial responded more quickly and maintained their antibody levels for longer compared to devils in the first trial. The different adjuvant combination incorporating the RNAase resistant polyICLC and imiquimod used in the second trial is likely to be responsible. The seroconversion in the majority of devils in these anti-DFTD immunization trials was remarkable, especially as DFTD is hallmarked by its immune evasion mechanisms. Microsatellite analyzes of MHC revealed that some MHC-I microsatellites correlated to stronger immune responses. These trials signify the first step in the long-term objective of releasing devils with immunity to DFTD into the wild.- Published
- 2018
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12. The toll-like receptor ligands Hiltonol ® (polyICLC) and imiquimod effectively activate antigen-specific immune responses in Tasmanian devils (Sarcophilus harrisii).
- Author
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Patchett AL, Tovar C, Corcoran LM, Lyons AB, and Woods GM
- Subjects
- Adjuvants, Immunologic, Animals, Cells, Cultured, Facial Neoplasms prevention & control, Hemocyanins immunology, Humans, Imiquimod, Immunity, Immunity, Innate, Immunization, Immunoglobulin G metabolism, Lymphocyte Activation, Polylysine immunology, Toll-Like Receptors agonists, Aminoquinolines immunology, Antigens immunology, Cancer Vaccines immunology, Carboxymethylcellulose Sodium analogs & derivatives, Facial Neoplasms immunology, Leukocytes, Mononuclear immunology, Marsupialia immunology, Poly I-C immunology, Polylysine analogs & derivatives
- Abstract
Devil facial tumour disease (DFTD) describes two genetically distinct transmissible tumours that pose a significant threat to the survival of the Tasmanian devil. A prophylactic vaccine could protect devils from DFTD transmission. For this vaccine to be effective, potent immune adjuvants will be required. Toll-like receptors (TLRs) promote robust immune responses in human cancer studies and are highly conserved across mammalian species. In this study, we investigated the proficiency of TLR ligands for immune activation in the Tasmanian devil using in vitro mononuclear cell stimulations and in vivo immunisation trials with a model antigen. We identified two such TLR ligands, polyICLC (Hiltonol
® ) (TLR3) and imiquimod (TLR7), that in combination induced significant IFNγ production from Tasmanian devil lymphocytes in vitro. Immunisation with these ligands and the model antigen keyhole limpet haemocyanin activated robust antigen-specific primary, secondary and long-term memory IgG responses. Our results support the conserved nature of TLR signaling across mammalian species. PolyICLC and imiquimod will be trialed as immune adjuvants in future DFTD vaccine formulations., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
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13. Regression of devil facial tumour disease following immunotherapy in immunised Tasmanian devils.
- Author
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Tovar C, Pye RJ, Kreiss A, Cheng Y, Brown GK, Darby J, Malley RC, Siddle HV, Skjødt K, Kaufman J, Silva A, Baz Morelli A, Papenfuss AT, Corcoran LM, Murphy JM, Pearse MJ, Belov K, Lyons AB, and Woods GM
- Subjects
- Animals, Antibody Formation immunology, Facial Neoplasms therapy, Facial Neoplasms veterinary, Female, Histocompatibility Antigens Class I immunology, Immunity, Humoral immunology, Male, Treatment Outcome, Facial Neoplasms immunology, Immunization methods, Immunotherapy methods, Marsupialia immunology
- Abstract
Devil facial tumour disease (DFTD) is a transmissible cancer devastating the Tasmanian devil (Sarcophilus harrisii) population. The cancer cell is the 'infectious' agent transmitted as an allograft by biting. Animals usually die within a few months with no evidence of antibody or immune cell responses against the DFTD allograft. This lack of anti-tumour immunity is attributed to an absence of cell surface major histocompatibility complex (MHC)-I molecule expression. While the endangerment of the devil population precludes experimentation on large experimental groups, those examined in our study indicated that immunisation and immunotherapy with DFTD cells expressing surface MHC-I corresponded with effective anti-tumour responses. Tumour engraftment did not occur in one of the five immunised Tasmanian devils, and regression followed therapy of experimentally induced DFTD tumours in three Tasmanian devils. Regression correlated with immune cell infiltration and antibody responses against DFTD cells. These data support the concept that immunisation of devils with DFTD cancer cells can successfully induce humoral responses against DFTD and trigger immune-mediated regression of established tumours. Our findings support the feasibility of a protective DFTD vaccine and ultimately the preservation of the species.
- Published
- 2017
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14. PD-L1 Is Not Constitutively Expressed on Tasmanian Devil Facial Tumor Cells but Is Strongly Upregulated in Response to IFN-γ and Can Be Expressed in the Tumor Microenvironment.
- Author
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Flies AS, Lyons AB, Corcoran LM, Papenfuss AT, Murphy JM, Knowles GW, Woods GM, and Hayball JD
- Abstract
The devil facial tumor disease (DFTD) is caused by clonal transmissible cancers that have led to a catastrophic decline in the wild Tasmanian devil ( Sarcophilus harrisii ) population. The first transmissible tumor, now termed devil facial tumor 1 (DFT1), was first discovered in 1996 and has been continually transmitted to new hosts for at least 20 years. In 2015, a second transmissible cancer [devil facial tumor 2 (DFT2)] was discovered in wild devils, and the DFT2 is genetically distinct and independent from the DFT1. Despite the estimated 136,559 base pair substitutions and 14,647 insertions/deletions in the DFT1 genome as compared to two normal devil reference genomes, the allograft tumors are not rejected by the host immune system. Additionally, genome sequencing of two sub-strains of DFT1 detected greater than 15,000 single-base substitutions that were found in only one of the DFT1 sub-strains, demonstrating the transmissible tumors are evolving and that generation of neoantigens is likely ongoing. Recent evidence in human clinical trials suggests that blocking PD-1:PD-L1 interactions promotes antitumor immune responses and is most effective in cancers with a high number of mutations. We hypothesized that DFTD cells could exploit the PD-1:PD-L1 inhibitory pathway to evade antitumor immune responses. We developed recombinant proteins and monoclonal antibodies (mAbs) to provide the first demonstration that PD-1 binds to both PD-L1 and PD-L2 in a non-placental mammal and show that PD-L1 is upregulated in DFTD cells in response to IFN-γ. Immunohistochemistry showed that PD-L1 is rarely expressed in primary tumor masses, but low numbers of PD-L1
+ non-tumor cells were detected in the microenvironment of several metastatic tumors. Importantly, in vitro testing suggests that PD-1 binding to PD-L1 and PD-L2 can be blocked by mAbs, which could be critical to understanding how the DFT allografts evade the immune system.- Published
- 2016
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15. Long-Lived Plasma Cells Have a Sweet Tooth.
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Corcoran LM and Nutt SL
- Subjects
- Antibodies, Humans, Glycolysis, Plasma Cells immunology
- Abstract
Long-lived plasma cells (LLPCs) are durable antibody-producing cells that are key to immunity. Bhattacharya and colleagues find that LLPCs derive their enhanced survival capacity from a higher rate of glucose import. Some of this glucose sustains the cells through glycolysis, while the bulk is required for antibody glycosylation., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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16. Id2 and E Proteins Orchestrate the Initiation and Maintenance of MLL-Rearranged Acute Myeloid Leukemia.
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Ghisi M, Kats L, Masson F, Li J, Kratina T, Vidacs E, Gilan O, Doyle MA, Newbold A, Bolden JE, Fairfax KA, de Graaf CA, Firth M, Zuber J, Dickins RA, Corcoran LM, Dawson MA, Belz GT, and Johnstone RW
- Subjects
- Animals, Cell Proliferation, Chromosomes, Human, Pair 21 genetics, Chromosomes, Human, Pair 8 genetics, Gene Expression Regulation, Leukemic, Humans, Inhibitor of Differentiation Protein 2 metabolism, Leukemia, Myeloid, Acute metabolism, Mice, Myeloid-Lymphoid Leukemia Protein metabolism, Neoplasms, Experimental, Oncogene Proteins, Fusion metabolism, Prognosis, Stem Cells cytology, Stem Cells metabolism, Survival Analysis, Transcription Factor 7-Like 2 Protein metabolism, Inhibitor of Differentiation Protein 2 genetics, Leukemia, Myeloid, Acute genetics, Leukemia, Myeloid, Acute pathology, Myeloid-Lymphoid Leukemia Protein genetics, Oncogene Proteins, Fusion genetics, Transcription Factor 7-Like 2 Protein genetics, Translocation, Genetic
- Abstract
E proteins and their antagonists, the Id proteins, are transcriptional regulators important for normal hematopoiesis. We found that Id2 acts as a key regulator of leukemia stem cell (LSC) potential in MLL-rearranged acute myeloid leukemia (AML). Low endogenous Id2 expression is associated with LSC enrichment while Id2 overexpression impairs MLL-AF9-leukemia initiation and growth. Importantly, MLL-AF9 itself controls the E-protein pathway by suppressing Id2 while directly activating E2-2 expression, and E2-2 depletion phenocopies Id2 overexpression in MLL-AF9-AML cells. Remarkably, Id2 tumor-suppressive function is conserved in t(8;21) AML. Low expression of Id2 and its associated gene signature are associated with poor prognosis in MLL-rearranged and t(8;21) AML patients, identifying the Id2/E-protein axis as a promising new therapeutic target in AML., (Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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17. Characterisation of CD4 T cells in healthy and diseased koalas (Phascolarctos cinereus) using cell-type-specific monoclonal antibodies.
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Mangar C, Armitage CW, Timms P, Corcoran LM, and Beagley KW
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- Amino Acid Sequence, Animals, Antibodies, Monoclonal, Murine-Derived chemistry, CD4 Antigens immunology, Cell Proliferation, Cell Separation, Flow Cytometry, Hybridomas, Immunoassay, Lymph Nodes metabolism, Mice, Inbred C57BL, Phylogeny, Spleen metabolism, CD4 Antigens metabolism, CD4-Positive T-Lymphocytes immunology, Phascolarctidae immunology
- Abstract
The koala (Phascolarctos cinereus) is an arboreal herbivorous marsupial that is an Australian icon. Koalas in many parts of Australia are under multiple threats including habitat destruction, dog attacks, vehicular accidents, and infectious diseases such as Chlamydia spp. and the koala retrovirus (KoRV), which may contribute to the incidence of lymphoma and leukaemia in this species. Due to a lack of koala-specific immune reagents and assays there is currently no way to adequately analyse the immune response in healthy, diseased or vaccinated animals. This paper reports the production and characterisation of the first anti-koala CD4 monoclonal antibody (mAb). The koala CD4 gene was identified and used to develop recombinant proteins for mAb production. Fluorochrome-conjugated anti-CD4 mAb was used to measure the levels of CD4(+) lymphocytes collected from koala spleens (41.1%, range 20-45.1%) lymph nodes (36.3%, range 19-55.9%) and peripheral blood (23.8%, range 17.3-35%) by flow cytometry. Biotin-conjugated anti-CD4 mAb was used for western blot to determine an approximate size of 52 kDa for the koala CD4 molecule and used in immunohistochemistry to identify CD4(+) cells in the paracortical region and germinal centres of spleen and lymph nodes. Using the anti-CD4 mab we showed that CD4 cells from vaccinated, but not control, koalas proliferated following in vitro stimulation with UV-inactivated Chlamydia pecorum and recombinant chlamydial antigens. Since CD4(+) T cells have been shown to play a pivotal role in clearing chlamydial infection in both human and mouse infections, using this novel antibody will help determine the role CD4(+) T cells play in protection against chlamydial infection in koalas and also enhance our knowledge of how KoRV affects the koala immune system., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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18. PU.1 cooperates with IRF4 and IRF8 to suppress pre-B-cell leukemia.
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Pang SH, Minnich M, Gangatirkar P, Zheng Z, Ebert A, Song G, Dickins RA, Corcoran LM, Mullighan CG, Busslinger M, Huntington ND, Nutt SL, and Carotta S
- Subjects
- Animals, B-Lymphocytes cytology, Gene Expression Regulation, Interferon Regulatory Factors genetics, Lymphopoiesis, Mice, Mice, Knockout, Precursor B-Cell Lymphoblastic Leukemia-Lymphoma prevention & control, Proto-Oncogene Proteins genetics, Trans-Activators genetics, Interferon Regulatory Factors physiology, Proto-Oncogene Proteins physiology, Trans-Activators physiology
- Abstract
The Ets family transcription factor PU.1 and the interferon regulatory factor (IRF)4 and IRF8 regulate gene expression by binding to composite DNA sequences known as Ets/interferon consensus elements. Although all three factors are expressed from the onset of B-cell development, single deficiency of these factors in B-cell progenitors only mildly impacts on bone marrow B lymphopoiesis. Here we tested whether PU.1 cooperates with IRF factors in regulating early B-cell development. Lack of PU.1 and IRF4 resulted in a partial block in development the pre-B-cell stage. The combined deletion of PU.1 and IRF8 reduced recirculating B-cell numbers. Strikingly, all PU.1/IRF4 and ~50% of PU.1/IRF8 double deficient mice developed pre-B-cell acute lymphoblastic leukemia (B-ALL) associated with reduced expression of the established B-lineage tumor suppressor genes, Ikaros and Spi-B. These genes are directly regulated by PU.1/IRF4/IRF8, and restoration of Ikaros or Spi-B expression inhibited leukemic cell growth. In summary, we demonstrate that PU.1, IRF4 and IRF8 cooperate to regulate early B-cell development and to prevent pre-B-ALL formation., Competing Interests: The authors declare no competing financial interests.
- Published
- 2016
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19. Dynamic changes in Id3 and E-protein activity orchestrate germinal center and plasma cell development.
- Author
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Gloury R, Zotos D, Zuidscherwoude M, Masson F, Liao Y, Hasbold J, Corcoran LM, Hodgkin PD, Belz GT, Shi W, Nutt SL, Tarlinton DM, and Kallies A
- Subjects
- Animals, Basic Helix-Loop-Helix Leucine Zipper Transcription Factors genetics, Basic Helix-Loop-Helix Transcription Factors genetics, Cell Differentiation genetics, Inhibitor of Differentiation Proteins genetics, Mice, Mice, Knockout, Positive Regulatory Domain I-Binding Factor 1, Receptors, CXCR4 genetics, Receptors, CXCR4 immunology, Transcription Factor 4, Transcription Factors genetics, Transcription Factors immunology, X-Box Binding Protein 1 genetics, X-Box Binding Protein 1 immunology, Basic Helix-Loop-Helix Leucine Zipper Transcription Factors immunology, Basic Helix-Loop-Helix Transcription Factors immunology, Cell Differentiation immunology, Germinal Center immunology, Inhibitor of Differentiation Proteins immunology, Plasma Cells immunology
- Abstract
The generation of high-affinity antibodies requires germinal center (GC) development and differentiation of long-lived plasma cells in a multilayered process that is tightly controlled by the activity of multiple transcription factors. Here, we reveal a new layer of complexity by demonstrating that dynamic changes in Id3 and E-protein activity govern both GC and plasma cell differentiation. We show that down-regulation of Id3 in B cells is essential for releasing E2A and E2-2, which in a redundant manner are required for antigen-induced B cell differentiation. We demonstrate that this pathway controls the expression of multiple key factors, including Blimp1, Xbp1, and CXCR4, and is therefore critical for establishing the transcriptional network that controls GC B cell and plasma cell differentiation., (© 2016 Gloury et al.)
- Published
- 2016
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- View/download PDF
20. RUNX2 Mediates Plasmacytoid Dendritic Cell Egress from the Bone Marrow and Controls Viral Immunity.
- Author
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Chopin M, Preston SP, Lun ATL, Tellier J, Smyth GK, Pellegrini M, Belz GT, Corcoran LM, Visvader JE, Wu L, and Nutt SL
- Abstract
Plasmacytoid dendritic cells (pDCs) represent a unique immune cell type that responds to viral nucleic acids through the rapid production of type I interferons. Within the hematopoietic system, the transcription factor RUNX2 is exclusively expressed in pDCs and is required for their peripheral homeostasis. Here, we show that RUNX2 plays an essential role in promoting pDC localization and function. RUNX2 is required for the appropriate expression of the integrin-mediated adhesion machinery, as well as for the down-modulation of the chemokine receptor CXCR4, which allows pDC egress into the circulation. RUNX2 also facilitates the robust response to viral infection through the control of IRF7, the major regulator of type I interferon production. Mice lacking one copy of Runx2 have reduced numbers of peripheral pDCs and IFN-α expression, which might contribute to the reported difficulties of individuals with cleidocranial dysplasia, who are haploinsufficient for RUNX2, to clear viral infections., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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- View/download PDF
21. NFκB1 is essential to prevent the development of multiorgan autoimmunity by limiting IL-6 production in follicular B cells.
- Author
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de Valle E, Grigoriadis G, O'Reilly LA, Willis SN, Maxwell MJ, Corcoran LM, Tsantikos E, Cornish JK, Fairfax KA, Vasanthakumar A, Febbraio MA, Hibbs ML, Pellegrini M, Banerjee A, Hodgkin PD, Kallies A, Mackay F, Strasser A, Gerondakis S, and Gugasyan R
- Subjects
- Animals, Autoimmune Diseases genetics, Autoimmune Diseases pathology, B-Lymphocytes pathology, Germinal Center pathology, Immunoglobulin M genetics, Immunoglobulin M immunology, Interleukin-6 genetics, Mice, Mice, Knockout, NF-kappa B p50 Subunit genetics, T-Lymphocytes, Helper-Inducer immunology, T-Lymphocytes, Helper-Inducer pathology, Transcription, Genetic genetics, Autoimmune Diseases immunology, B-Lymphocytes immunology, Germinal Center immunology, Interleukin-6 immunology, NF-kappa B p50 Subunit immunology, Transcription, Genetic immunology
- Abstract
We examined the role of NFκB1 in the homeostasis and function of peripheral follicular (Fo) B cells. Aging mice lacking NFκB1 (Nfκb1(-/-)) develop lymphoproliferative and multiorgan autoimmune disease attributed in large part to the deregulated activity of Nfκb1(-/-)Fo B cells that produce excessive levels of the proinflammatory cytokine interleukin 6 (IL-6). Despite enhanced germinal center (GC) B cell differentiation, the formation of GC structures was severely disrupted in the Nfκb1(-/-)mice. Bone marrow chimeric mice revealed that the Fo B cell-intrinsic loss of NFκB1 led to the spontaneous generation of GC B cells. This was primarily the result of an increase in IL-6 levels, which promotes the differentiation of Fo helper CD4(+)T cells and acts in an autocrine manner to reduce antigen receptor and toll-like receptor activation thresholds in a population of proliferating IgM(+)Nfκb1(-/-)Fo B cells. We demonstrate that p50-NFκB1 represses Il-6 transcription in Fo B cells, with the loss of NFκB1 also resulting in the uncontrolled RELA-driven transcription of Il-6.Collectively, our findings identify a previously unrecognized role for NFκB1 in preventing multiorgan autoimmunity through its negative regulation of Il-6 gene expression in Fo B cells., (© 2016 de Valle et al.)
- Published
- 2016
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22. The Helix-Loop-Helix Protein ID2 Governs NK Cell Fate by Tuning Their Sensitivity to Interleukin-15.
- Author
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Delconte RB, Shi W, Sathe P, Ushiki T, Seillet C, Minnich M, Kolesnik TB, Rankin LC, Mielke LA, Zhang JG, Busslinger M, Smyth MJ, Hutchinson DS, Nutt SL, Nicholson SE, Alexander WS, Corcoran LM, Vivier E, Belz GT, Carotta S, and Huntington ND
- Subjects
- Animals, Cell Lineage immunology, Cells, Cultured, Female, Flow Cytometry, Male, Mice, Mice, Mutant Strains, Receptors, Interleukin-15 immunology, Receptors, Interleukin-15 metabolism, Reverse Transcriptase Polymerase Chain Reaction, Transcription Factors immunology, Transcription Factors metabolism, Cell Differentiation immunology, Inhibitor of Differentiation Protein 2 immunology, Interleukin-15 immunology, Killer Cells, Natural cytology, Killer Cells, Natural immunology
- Abstract
The inhibitor of DNA binding 2 (Id2) is essential for natural killer (NK) cell development with its canonical role being to antagonize E-protein function and alternate lineage fate. Here we have identified a key role for Id2 in regulating interleukin-15 (IL-15) receptor signaling and homeostasis of NK cells by repressing multiple E-protein target genes including Socs3. Id2 deletion in mature NK cells was incompatible with their homeostasis due to impaired IL-15 receptor signaling and metabolic function and this could be rescued by strong IL-15 receptor stimulation or genetic ablation of Socs3. During NK cell maturation, we observed an inverse correlation between E-protein target genes and Id2. These results shift the current paradigm on the role of ID2, indicating that it is required not only to antagonize E-proteins during NK cell commitment, but constantly required to titrate E-protein activity to regulate NK cell fitness and responsiveness to IL-15., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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23. The flavors of plasma cells.
- Author
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Corcoran LM and Nutt SL
- Subjects
- Animals, Cell Division genetics, Humans, B-Lymphocytes metabolism, Cell Differentiation genetics, Plasma Cells metabolism, Transcriptome
- Published
- 2015
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- View/download PDF
24. The transcription factors IRF8 and PU.1 negatively regulate plasma cell differentiation.
- Author
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Carotta S, Willis SN, Hasbold J, Inouye M, Pang SH, Emslie D, Light A, Chopin M, Shi W, Wang H, Morse HC 3rd, Tarlinton DM, Corcoran LM, Hodgkin PD, and Nutt SL
- Subjects
- Animals, Cell Line, Cluster Analysis, Gene Expression Profiling, Gene Expression Regulation, Humans, Immunoglobulin Class Switching genetics, Interferon Regulatory Factors metabolism, Mice, Mice, Transgenic, Plasma Cells immunology, Protein Binding, Proto-Oncogene Proteins metabolism, Trans-Activators metabolism, Cell Differentiation genetics, Interferon Regulatory Factors genetics, Plasma Cells cytology, Plasma Cells metabolism, Proto-Oncogene Proteins genetics, Trans-Activators genetics
- Abstract
Activated B cells undergo immunoglobulin class-switch recombination (CSR) and differentiate into antibody-secreting plasma cells. The distinct transcriptomes of B cells and plasma cells are maintained by the antagonistic influences of two groups of transcription factors: those that maintain the B cell program, including BCL6 and PAX5, and plasma cell-promoting factors, such as IRF4 and BLIMP-1. We show that the complex of IRF8 and PU.1 controls the propensity of B cells to undergo CSR and plasma cell differentiation by concurrently promoting the expression of BCL6 and PAX5 and repressing AID and BLIMP-1. As the PU.1-IRF8 complex functions in a reciprocal manner to IRF4, we propose that concentration-dependent competition between these factors controls B cell terminal differentiation., (© 2014 Carotta et al.)
- Published
- 2014
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25. The BTB-ZF transcription factor Zbtb20 is driven by Irf4 to promote plasma cell differentiation and longevity.
- Author
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Chevrier S, Emslie D, Shi W, Kratina T, Wellard C, Karnowski A, Erikci E, Smyth GK, Chowdhury K, Tarlinton D, and Corcoran LM
- Subjects
- Animals, Bromodeoxyuridine, Chromatin Immunoprecipitation, Enzyme-Linked Immunosorbent Assay, Enzyme-Linked Immunospot Assay, Flow Cytometry, Gene Expression Regulation genetics, Immunohistochemistry, Mice, Microarray Analysis, Plasma Cells physiology, Real-Time Polymerase Chain Reaction, Sequence Analysis, RNA, Statistics, Nonparametric, B-Lymphocytes metabolism, Cell Differentiation physiology, Cell Survival physiology, Gene Expression Regulation physiology, Interferon Regulatory Factors metabolism, Transcription Factors metabolism
- Abstract
The transcriptional network regulating antibody-secreting cell (ASC) differentiation has been extensively studied, but our current understanding is limited. The mechanisms of action of known "master" regulators are still unclear, while the participation of new factors is being revealed. Here, we identify Zbtb20, a Bcl6 homologue, as a novel regulator of late B cell development. Within the B cell lineage, Zbtb20 is specifically expressed in B1 and germinal center B cells and peaks in long-lived bone marrow (BM) ASCs. Unlike Bcl6, an inhibitor of ASC differentiation, ectopic Zbtb20 expression in primary B cells facilitates terminal B cell differentiation to ASCs. In plasma cell lines, Zbtb20 induces cell survival and blocks cell cycle progression. Immunized Zbtb20-deficient mice exhibit curtailed humoral responses and accelerated loss of antigen-specific plasma cells, specifically from the BM pool. Strikingly, Zbtb20 induction does not require Blimp1 but depends directly on Irf4, acting at a newly identified Zbtb20 promoter in ASCs. These results identify Zbtb20 as an important player in late B cell differentiation and provide new insights into this complex process.
- Published
- 2014
- Full Text
- View/download PDF
26. Fas ligand-mediated immune surveillance by T cells is essential for the control of spontaneous B cell lymphomas.
- Author
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Afshar-Sterle S, Zotos D, Bernard NJ, Scherger AK, Rödling L, Alsop AE, Walker J, Masson F, Belz GT, Corcoran LM, O'Reilly LA, Strasser A, Smyth MJ, Johnstone R, Tarlinton DM, Nutt SL, and Kallies A
- Subjects
- Animals, CD8-Positive T-Lymphocytes cytology, Cell Separation, Cell Transformation, Neoplastic, DNA-Binding Proteins metabolism, Disease Models, Animal, Flow Cytometry, Genes, Tumor Suppressor, Immunologic Surveillance genetics, Mice, Mice, Transgenic, Mutation, Positive Regulatory Domain I-Binding Factor 1, Proto-Oncogene Proteins c-bcl-6, Transcription Factors physiology, B-Lymphocytes pathology, Fas Ligand Protein metabolism, Lymphoma, Large B-Cell, Diffuse genetics, Lymphoma, Large B-Cell, Diffuse immunology, T-Lymphocytes immunology, Transcription Factors genetics
- Abstract
Loss of function of the tumor suppressor gene PRDM1 (also known as BLIMP1) or deregulated expression of the oncogene BCL6 occurs in a large proportion of diffuse large B cell lymphoma (DLBCL) cases. However, targeted mutation of either gene in mice leads to only slow and infrequent development of malignant lymphoma, and despite frequent mutation of BCL6 in activated B cells of healthy individuals, lymphoma development is rare. Here we show that T cells prevent the development of overt lymphoma in mice caused by Blimp1 deficiency or overexpression of Bcl6 in the B cell lineage. Impairment of T cell control results in rapid development of DLBCL-like disease, which can be eradicated by polyclonal CD8(+) T cells in a T cell receptor-, CD28- and Fas ligand-dependent manner. Thus, malignant transformation of mature B cells requires mutations that impair intrinsic differentiation processes and permit escape from T cell-mediated tumor surveillance.
- Published
- 2014
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- View/download PDF
27. B and T cells collaborate in antiviral responses via IL-6, IL-21, and transcriptional activator and coactivator, Oct2 and OBF-1.
- Author
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Karnowski A, Chevrier S, Belz GT, Mount A, Emslie D, D'Costa K, Tarlinton DM, Kallies A, and Corcoran LM
- Subjects
- Animals, Antibodies, Viral immunology, B-Lymphocytes metabolism, Blotting, Western, Flow Cytometry, Gene Expression Regulation immunology, Germinal Center immunology, Germinal Center metabolism, Germinal Center virology, Host-Pathogen Interactions immunology, Influenza A Virus, H3N2 Subtype immunology, Influenza A Virus, H3N2 Subtype physiology, Interleukin-6 deficiency, Interleukin-6 genetics, Interleukins genetics, Interleukins metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Octamer Transcription Factor-2 genetics, Octamer Transcription Factor-2 metabolism, Orthomyxoviridae Infections genetics, Orthomyxoviridae Infections immunology, Orthomyxoviridae Infections virology, Reverse Transcriptase Polymerase Chain Reaction, T-Lymphocytes metabolism, T-Lymphocytes, Helper-Inducer immunology, T-Lymphocytes, Helper-Inducer metabolism, Trans-Activators genetics, Trans-Activators metabolism, B-Lymphocytes immunology, Interleukin-6 immunology, Interleukins immunology, Octamer Transcription Factor-2 immunology, T-Lymphocytes immunology, Trans-Activators immunology
- Abstract
A strong humoral response to infection requires the collaboration of several hematopoietic cell types that communicate via antigen presentation, surface coreceptors and their ligands, and secreted factors. The proinflammatory cytokine IL-6 has been shown to promote the differentiation of activated CD4(+) T cells into T follicular helper cells (T(FH) cells) during an immune response. T(FH) cells collaborate with B cells in the formation of germinal centers (GCs) during T cell-dependent antibody responses, in part through secretion of critical cytokines such as IL-21. In this study, we demonstrate that loss of either IL-6 or IL-21 has marginal effects on the generation of T(FH) cells and on the formation of GCs during the response to acute viral infection. However, mice lacking both IL-6 and IL-21 were unable to generate a robust T(FH) cell-dependent immune response. We found that IL-6 production in follicular B cells in the draining lymph node was an important early event during the antiviral response and that B cell-derived IL-6 was necessary and sufficient to induce IL-21 from CD4(+) T cells in vitro and to support T(FH) cell development in vivo. Finally, the transcriptional activator Oct2 and its cofactor OBF-1 were identified as regulators of Il6 expression in B cells.
- Published
- 2012
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28. IL-21 regulates germinal center B cell differentiation and proliferation through a B cell-intrinsic mechanism.
- Author
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Zotos D, Coquet JM, Zhang Y, Light A, D'Costa K, Kallies A, Corcoran LM, Godfrey DI, Toellner KM, Smyth MJ, Nutt SL, and Tarlinton DM
- Subjects
- Adaptive Immunity, Animals, Cell Proliferation, DNA-Binding Proteins biosynthesis, DNA-Binding Proteins immunology, Germinal Center cytology, Germinal Center immunology, Germinal Center metabolism, Interleukins metabolism, Mice, Mice, Inbred C57BL, Plasma Cells cytology, Plasma Cells immunology, Proto-Oncogene Proteins c-bcl-6, Receptors, Interleukin-21 immunology, Receptors, Interleukin-21 metabolism, T-Lymphocytes, Helper-Inducer immunology, B-Lymphocytes cytology, B-Lymphocytes immunology, Cell Differentiation immunology, Interleukins immunology, Lymphocyte Activation
- Abstract
Germinal centers (GCs) are sites of B cell proliferation, somatic hypermutation, and selection of variants with improved affinity for antigen. Long-lived memory B cells and plasma cells are also generated in GCs, although how B cell differentiation in GCs is regulated is unclear. IL-21, secreted by T follicular helper cells, is important for adaptive immune responses, although there are conflicting reports on its target cells and mode of action in vivo. We show that the absence of IL-21 signaling profoundly affects the B cell response to protein antigen, reducing splenic and bone marrow plasma cell formation and GC persistence and function, influencing their proliferation, transition into memory B cells, and affinity maturation. Using bone marrow chimeras, we show that these activities are primarily a result of CD3-expressing cells producing IL-21 that acts directly on B cells. Molecularly, IL-21 maintains expression of Bcl-6 in GC B cells. The absence of IL-21 or IL-21 receptor does not abrogate the appearance of T cells in GCs or the appearance of CD4 T cells with a follicular helper phenotype. IL-21 thus controls fate choices of GC B cells directly.
- Published
- 2010
- Full Text
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29. Blimp1 is limiting for transformation in a mouse plasmacytoma model.
- Author
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D'Costa K, Emslie D, Metcalf D, Smyth GK, Karnowski A, Kallies A, Nutt SL, and Corcoran LM
- Subjects
- Alleles, Animals, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic pathology, Disease Models, Animal, Female, Genotype, Male, Mice, Mice, Transgenic, Phenotype, Plasmacytoma genetics, Plasmacytoma pathology, Positive Regulatory Domain I-Binding Factor 1, Transcription Factors genetics, Cell Transformation, Neoplastic metabolism, Plasmacytoma metabolism, Transcription Factors metabolism
- Abstract
Multiple myeloma (MM) and plasmacytomas are cancers of antibody-secreting cells (ASCs). PRDM1/BLIMP1 is an essential regulator of ASC development. Histologic evidence shows that 100% of MM expresses PRDM1/BLIMP1, indicating that PRDM1/BLIMP1 is important for the development or persistence of MM. In contrast, some diffuse large B-cell lymphomas (DLBCLs) lose PRDM1 expression, suggesting that PRDM1 may act as a tumor suppressor in DLBCL. Thus, the role of PRDM1/BLIMP1 in transformation of mature B cells is unclear. We have used a plasmacytoma-prone transgenic mouse model to study the effect of Blimp1 loss on plasmacytoma prevalence, latency, and phenotype. Two possible outcomes could be envisaged: loss of Blimp1 might decrease plasmacytoma prevalence, through reduction of plasma cells, and so the number of susceptible transformation targets. Alternatively, Blimp1 may participate in the transformation process itself. Our results support the latter scenario, showing that decreasing Blimp1 dosage does not change plasma cell number in nontransgenic mice in vivo, but it significantly reduces plasmacytoma prevalence in transgenic mice. Loss of functional Blimp1 completely prevents plasmacytoma formation in this tumor model. These observations suggest that Blimp1 is limiting for plasma cell transformation and thus has potential as a target for new therapies to combat MM.
- Published
- 2009
- Full Text
- View/download PDF
30. CD93 is required for maintenance of antibody secretion and persistence of plasma cells in the bone marrow niche.
- Author
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Chevrier S, Genton C, Kallies A, Karnowski A, Otten LA, Malissen B, Malissen M, Botto M, Corcoran LM, Nutt SL, and Acha-Orbea H
- Subjects
- Animals, Cell Differentiation, Chickens, Ikaros Transcription Factor, Immunization, Mammary Tumor Virus, Mouse immunology, Mice, Plasma Cells cytology, Positive Regulatory Domain I-Binding Factor 1, Retroviridae Infections immunology, Syndecan-1 immunology, T-Lymphocytes immunology, Trans-Activators immunology, Transcription Factors immunology, gamma-Globulins immunology, Antibody Formation immunology, Bone Marrow immunology, Membrane Glycoproteins immunology, Plasma Cells immunology, Receptors, Complement immunology
- Abstract
Plasma cells represent the end stage of B-cell development and play a key role in providing an efficient antibody response, but they are also involved in numerous pathologies. Here we show that CD93, a receptor expressed during early B-cell development, is reinduced during plasma-cell differentiation. High CD93/CD138 expression was restricted to antibody-secreting cells both in T-dependent and T-independent responses as naive, memory, and germinal-center B cells remained CD93-negative. CD93 was expressed on (pre)plasmablasts/plasma cells, including long-lived plasma cells that showed decreased cell cycle activity, high levels of isotype-switched Ig secretion, and modification of the transcriptional network. T-independent and T-dependent stimuli led to re-expression of CD93 via 2 pathways, either before or after CD138 or Blimp-1 expression. Strikingly, while humoral immune responses initially proceeded normally, CD93-deficient mice were unable to maintain antibody secretion and bone-marrow plasma-cell numbers, demonstrating that CD93 is important for the maintenance of plasma cells in bone marrow niches.
- Published
- 2009
- Full Text
- View/download PDF
31. Oct2 enhances antibody-secreting cell differentiation through regulation of IL-5 receptor alpha chain expression on activated B cells.
- Author
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Emslie D, D'Costa K, Hasbold J, Metcalf D, Takatsu K, Hodgkin PO, and Corcoran LM
- Subjects
- Animals, Antibody-Producing Cells drug effects, Antibody-Producing Cells immunology, B-Lymphocytes cytology, B-Lymphocytes drug effects, Cell Differentiation drug effects, Cell Differentiation immunology, Cell Line, Eosinophils drug effects, Eosinophils immunology, Gene Expression Regulation drug effects, Interleukin-5 pharmacology, Interleukin-5 Receptor alpha Subunit genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Octamer Transcription Factor-2 deficiency, Octamer Transcription Factor-2 genetics, Positive Regulatory Domain I-Binding Factor 1, RNA, Messenger metabolism, Repressor Proteins genetics, Repressor Proteins immunology, Spleen cytology, T-Lymphocytes drug effects, T-Lymphocytes immunology, Transcription Factors genetics, Transcription Factors immunology, Antibody-Producing Cells cytology, B-Lymphocytes immunology, Interleukin-5 Receptor alpha Subunit immunology, Octamer Transcription Factor-2 immunology
- Abstract
Mice lacking a functional gene for the Oct2 transcriptional activator display several developmental and functional deficiencies in the B lymphocyte lineage. These include defective B cell receptor (BCR) and Toll-like receptor 4 signaling, an absence of B-1 and marginal zone populations, and globally reduced levels of serum immunoglobulin (Ig) in naive and immunized animals. Oct2 was originally identified through its ability to bind to regulatory regions in the Ig loci, but genetic evidence has not supported an essential role for Oct2 in the expression of Ig genes. We describe a new Oct2-mediated role in B cells. Oct2 augments the ability of activated B cells to differentiate to antibody-secreting plasma cells (ASCs) under T cell-dependent conditions through direct regulation of the gene encoding the alpha chain of the interleukin (IL) 5 receptor. Ectopic expression of IL-5Ralpha in oct2-deficient B cells largely restores their ability to differentiate to functional ASCs in vitro but does not correct other phenotypic defects in the mutants, such as the maturation and specialization of peripheral B cells, which must therefore rely on distinct Oct2 target genes. IL-5 augments ASC differentiation in vitro, and we show that IL-5 directly activates the plasma cell differentiation program by enhancing blimp1 expression.
- Published
- 2008
- Full Text
- View/download PDF
32. Silencing and nuclear repositioning of the lambda5 gene locus at the pre-B cell stage requires Aiolos and OBF-1.
- Author
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Karnowski A, Cao C, Matthias G, Carotta S, Corcoran LM, Martensson IL, Skok JA, and Matthias P
- Subjects
- Animals, Bone Marrow Cells metabolism, Bone Marrow Cells physiology, Cell Differentiation genetics, Cell Differentiation immunology, Cell Nucleus genetics, Cells, Cultured, Gene Expression Profiling, Gene Expression Regulation immunology, Ikaros Transcription Factor, Immunoglobulin lambda-Chains metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Oligonucleotide Array Sequence Analysis, Precursor Cells, B-Lymphoid physiology, Trans-Activators genetics, Gene Order physiology, Gene Rearrangement, B-Lymphocyte, Light Chain, Gene Silencing immunology, Immunoglobulin lambda-Chains genetics, Precursor Cells, B-Lymphoid metabolism, Trans-Activators physiology
- Abstract
The chromatin regulator Aiolos and the transcriptional coactivator OBF-1 have been implicated in regulating aspects of B cell maturation and activation. Mice lacking either of these factors have a largely normal early B cell development. However, when both factors are eliminated simultaneously a block is uncovered at the transition between pre-B and immature B cells, indicating that these proteins exert a critical function in developing B lymphocytes. In mice deficient for Aiolos and OBF-1, the numbers of immature B cells are reduced, small pre-BII cells are increased and a significant impairment in immunoglobulin light chain DNA rearrangement is observed. We identified genes whose expression is deregulated in the pre-B cell compartment of these mice. In particular, we found that components of the pre-BCR, such as the surrogate light chain genes lambda5 and VpreB, fail to be efficiently silenced in double-mutant mice. Strikingly, developmentally regulated nuclear repositioning of the lambda5 gene is impaired in pre-B cells lacking OBF-1 and Aiolos. These studies uncover a novel role for OBF-1 and Aiolos in controlling the transcription and nuclear organization of genes involved in pre-BCR function.
- Published
- 2008
- Full Text
- View/download PDF
33. Initiation of plasma-cell differentiation is independent of the transcription factor Blimp-1.
- Author
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Kallies A, Hasbold J, Fairfax K, Pridans C, Emslie D, McKenzie BS, Lew AM, Corcoran LM, Hodgkin PD, Tarlinton DM, and Nutt SL
- Subjects
- Animals, Antibodies immunology, Antigen-Presenting Cells cytology, Antigen-Presenting Cells immunology, Antigen-Presenting Cells metabolism, B-Lymphocytes metabolism, Cells, Cultured, DNA metabolism, Gene Expression Regulation, Immunoglobulin G metabolism, Mice, Mice, Inbred C57BL, Mice, Transgenic, Mutation genetics, PAX5 Transcription Factor metabolism, Plasma Cells immunology, Positive Regulatory Domain I-Binding Factor 1, Protein Binding, Repressor Proteins genetics, Transcription Factors deficiency, Transcription Factors genetics, Cell Differentiation immunology, Plasma Cells cytology, Plasma Cells metabolism, Repressor Proteins metabolism, Transcription Factors metabolism
- Abstract
Blimp-1 is considered an essential regulator of the terminal differentiation of B cells into antibody-secreting plasma cells. We show here that Rag1-/- mice reconstituted with fetal liver cells homozygous for a DNA-binding-deficient mutant of Prdm1 (the gene encoding Blimp-1) lack a defined plasma-cell compartment, yet show detectable amounts of all immunoglobulin isotypes. In vitro analysis revealed that Blimp-1 is not required for the initiation of antibody secretion but is essential for subsequent high immunoglobulin production. Blimp-1-independent differentiation was blocked at a preplasmablast stage characterized by decreased Pax5 expression and the activation of plasma-cell genes. Analysis of Blimp-1-sufficient differentiation revealed a phase prior to Blimp-1 expression in which several genes normally repressed by Pax5 are re-expressed, suggesting that plasma-cell differentiation is initiated by the inhibition of Pax5 function. Our results indicate that full plasma-cell differentiation but not commitment to the plasma-cell fate requires the expression of functional Blimp-1.
- Published
- 2007
- Full Text
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34. An inducible enhancer required for Il12b promoter activity in an insulated chromatin environment.
- Author
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Zhou L, Nazarian AA, Xu J, Tantin D, Corcoran LM, and Smale ST
- Subjects
- Animals, Base Sequence, Cell Line, Deoxyribonuclease I metabolism, Interleukin-12 Subunit p40 genetics, Lipopolysaccharides pharmacology, Macrophage Activation, Mice, Molecular Sequence Data, Nucleosomes metabolism, Octamer Transcription Factor-1 metabolism, Octamer Transcription Factor-2 metabolism, Transcription Initiation Site, Chromatin metabolism, Enhancer Elements, Genetic, Interleukin-12 Subunit p40 metabolism, Macrophages metabolism, Promoter Regions, Genetic
- Abstract
Interleukin-12 (IL-12) and IL-23 are heterodimeric cytokines that serve as critical regulators of T helper cell development. The Il12b gene, which encodes the p40 subunit of both IL-12 and IL-23, is expressed in macrophages and dendritic cells following induction by bacterial products. Although the Il12b promoter, like the promoters of most proinflammatory genes, can support transcriptional induction in typical transfection assays, we show that it is not sufficient for transcription in an insulated chromatin environment. Using a DNase I hypersensitivity assay, two potential distal control regions were identified. One region, DNase I-hypersensitive site 1 (HSS1), located 10 kb upstream of the transcription start site, exhibited hypersensitivity only in stimulated macrophages. In an insulated environment, a 105-bp fragment spanning HSS1 was sufficient for transcription when combined with the Il12b promoter. Although several elements are likely to contribute to activity of the endogenous HSS1 enhancer, including an evolutionarily conserved binding site for C/EBP proteins, the only element required for activity in transient- and stable-transfection assays bound Oct-1 and Oct-2, both of which are expressed constitutively in macrophages. Oct-1 and Oct-2 were recruited to the enhancer upon macrophage stimulation, and the Oct site appeared important for nucleosome remodeling at HSS1. These results suggest that the HSS1 enhancer and Oct proteins play central roles in Il12b induction upon macrophage activation.
- Published
- 2007
- Full Text
- View/download PDF
35. Normalization of boutique two-color microarrays with a high proportion of differentially expressed probes.
- Author
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Oshlack A, Emslie D, Corcoran LM, and Smyth GK
- Subjects
- Animals, B-Lymphocytes metabolism, Color, Mice, Up-Regulation genetics, DNA Probes genetics, Gene Expression Profiling, Oligonucleotide Array Sequence Analysis methods
- Abstract
Normalization is critical for removing systematic variation from microarray data. For two-color microarray platforms, intensity-dependent lowess normalization is commonly used to correct relative gene expression values for biases. Here we outline a normalization method for use when the assumptions of lowess normalization fail. Specifically, this can occur when specialized boutique arrays are constructed that contain a subset of genes selected to test particular biological functions.
- Published
- 2007
- Full Text
- View/download PDF
36. The Ets factor Spi-B is a direct critical target of the coactivator OBF-1.
- Author
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Bartholdy B, Du Roure C, Bordon A, Emslie D, Corcoran LM, and Matthias P
- Subjects
- Animals, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Humans, In Situ Hybridization, Mice, Mice, Transgenic, Oligonucleotide Array Sequence Analysis, Phenotype, Proto-Oncogene Proteins c-ets genetics, Receptors, Antigen, B-Cell metabolism, Signal Transduction physiology, T-Lymphocytes metabolism, Trans-Activators genetics, Transcription Factors genetics, Transcription Factors metabolism, Proto-Oncogene Proteins c-ets metabolism, Trans-Activators metabolism, Transcription, Genetic
- Abstract
OBF-1 (Bob.1, OCA-B) is a lymphoid-specific transcriptional coactivator that associates with the transcription factors Oct-1 or Oct-2 on the conserved octamer element present in the promoters of several ubiquitous and lymphoid-specific genes. OBF-1-deficient mice have B cell-intrinsic defects, lack germinal centers, and have severely impaired immune responses to T cell-dependent antigens. Crucial genes that are regulated by OBF-1 and that might explain the observed phenotype of OBF-1 deficiency have remained elusive to date. Here we have generated transgenic mice expressing OBF-1 specifically in T cells and examined these together with mice lacking OBF-1 to discover transcriptional targets of this coactivator. Using microarray analysis, we have identified the Ets transcription factor Spi-B as a direct target gene critically regulated by OBF-1 that can help explain the phenotype of OBF-1-deficient mice. Spi-B has been implicated in signaling pathways downstream of the B cell receptor and is essential for germinal center formation and maintenance. The present findings establish a hierarchy between these two factors and provide a molecular link between OBF-1 and B cell receptor signaling.
- Published
- 2006
- Full Text
- View/download PDF
37. Monocytic leukemia zinc finger protein is essential for the development of long-term reconstituting hematopoietic stem cells.
- Author
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Thomas T, Corcoran LM, Gugasyan R, Dixon MP, Brodnicki T, Nutt SL, Metcalf D, and Voss AK
- Subjects
- Animals, Cell Differentiation, Cell Lineage, Embryo Loss, Hematopoietic Stem Cells cytology, Histone Acetyltransferases genetics, Liver cytology, Liver embryology, Mice, Mice, Mutant Strains, Organ Specificity, T-Lymphocytes cytology, T-Lymphocytes physiology, Thymus Gland cytology, Thymus Gland embryology, Zinc Fingers, Hematopoietic Stem Cells physiology, Histone Acetyltransferases physiology
- Abstract
Monocytic leukemia zinc finger protein (MOZ), a transcriptional coactivator and member of the MYST family of histone acetyltransferases, is the target of recurrent translocations in acute myeloid leukemia. Since genes associated with translocations in leukemia are typically important regulators of blood formation, we investigated if Moz has a role in normal hematopoiesis. We generated mice carrying a mutation in the Moz gene. Homozygous Moz mutant mice died at birth. Moz mutant fetal liver hematopoietic cells were incapable of contributing to the hematopoietic system of recipients after transplantation. We observed profound defects in the stem cell compartment of Moz-deficient mice. Progenitors of all lineages were reduced in number. However, blood cell lineage commitment was unaffected. Together, these results show that Moz is essential for a fundamental property of hematopoietic stem cells, the ability to reconstitute the hematopoietic system of a recipient after transplantation and that Moz is specifically required in the stem cell compartment.
- Published
- 2006
- Full Text
- View/download PDF
38. Repression of Flt3 by Pax5 is crucial for B-cell lineage commitment.
- Author
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Holmes ML, Carotta S, Corcoran LM, and Nutt SL
- Subjects
- Animals, Cell Line, Chromatin Immunoprecipitation, Electrophoretic Mobility Shift Assay, Flow Cytometry, Mice, PAX5 Transcription Factor metabolism, Polymerase Chain Reaction, Protein Binding, B-Lymphocytes cytology, Cell Lineage, Gene Expression Regulation, Developmental physiology, PAX5 Transcription Factor physiology, fms-Like Tyrosine Kinase 3 genetics
- Abstract
Early B-lymphopoiesis requires the growth-factor receptors, IL-7R and Flt3, and the activity of a number of transcription factors. One factor, Pax5, is required for commitment to the B-cell lineage, although the molecular mechanism by which this occurs is unknown. We demonstrate here that an important function of Pax5 is to repress Flt3 transcription in B-cell progenitors, as Pax5-deficient pro-B cells express abundant Flt3 that is rapidly silenced upon the reintroduction of Pax5, whereas enforced expression of Flt3 in wild-type progenitors significantly impairs B-cell development. These findings demonstrate that the repression of Flt3 by Pax5 is essential for normal B-lymphopoiesis.
- Published
- 2006
- Full Text
- View/download PDF
39. Differential requirement for OBF-1 during antibody-secreting cell differentiation.
- Author
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Corcoran LM, Hasbold J, Dietrich W, Hawkins E, Kallies A, Nutt SL, Tarlinton DM, Matthias P, and Hodgkin PD
- Subjects
- Animals, Antibody-Producing Cells metabolism, Cells, Cultured, DNA Primers, DNA-Binding Proteins metabolism, Enzyme-Linked Immunosorbent Assay, Flow Cytometry, Genetic Complementation Test, Lipopolysaccharides, Mice, Mice, Inbred C57BL, Mice, Knockout, PAX5 Transcription Factor, Plasma Cells metabolism, Positive Regulatory Domain I-Binding Factor 1, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-bcl-6, Repressor Proteins metabolism, Reverse Transcriptase Polymerase Chain Reaction, Trans-Activators metabolism, Transcription Factors metabolism, Antibody-Producing Cells physiology, Cell Differentiation physiology, Gene Expression Regulation, Trans-Activators physiology
- Abstract
Resting B cells can be cultured to induce antibody-secreting cell (ASC) differentiation in vitro. A quantitative analysis of cell behavior during such a culture allows the influences of different stimuli and gene products to be measured. The application of this analytical system revealed that the OBF-1 transcriptional coactivator, whose loss impairs antibody production in vivo, has two effects on ASC development. Although OBF-1 represses early T cell-dependent (TD) differentiation, it is also critical for the completion of the final stages of ASC development. Under these conditions, the loss of OBF-1 blocks the genetic program of ASC differentiation so that Blimp-1/prdm1 induction fails, and bcl-6, Pax5, and AID are not repressed as in control ASC. Retroviral complementation confirmed that OBF-1 was the critical entity. Surprisingly, when cells were cultured in lipopolysaccharide to mimic T cell-independent conditions, OBF-1-null B cells differentiated normally to ASC. In the OBF-1(-/-) ASC generated under either culture regimen, antibody production was normal or only modestly reduced, revealing that Ig genes are not directly dependent on OBF-1 for their expression. The differential requirement for OBF-1 in TD ASC generation was confirmed in vivo. These studies define a new regulatory role for OBF-1 in determining the cell-autonomous capacity of B cells to undergo terminal differentiation in response to different immunological signals.
- Published
- 2005
- Full Text
- View/download PDF
40. Plasma cell ontogeny defined by quantitative changes in blimp-1 expression.
- Author
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Kallies A, Hasbold J, Tarlinton DM, Dietrich W, Corcoran LM, Hodgkin PD, and Nutt SL
- Subjects
- Animals, Antibody-Producing Cells metabolism, Cell Differentiation, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Phenotype, Positive Regulatory Domain I-Binding Factor 1, Repressor Proteins physiology, Transcription Factors physiology, Gene Expression Regulation, Plasma Cells cytology, Repressor Proteins genetics, Transcription Factors genetics
- Abstract
Plasma cells comprise a population of terminally differentiated B cells that are dependent on the transcriptional regulator B lymphocyte--induced maturation protein 1 (Blimp-1) for their development. We have introduced a gfp reporter into the Blimp-1 locus and shown that heterozygous mice express the green fluorescent protein in all antibody-secreting cells (ASCs) in vivo and in vitro. In vitro, these cells display considerable heterogeneity in surface phenotype, immunoglobulin secretion rate, and Blimp-1 expression levels. Importantly, analysis of in vivo ASCs induced by immunization reveals a developmental pathway in which increasing levels of Blimp-1 expression define developmental stages of plasma cell differentiation that have many phenotypic and molecular correlates. Thus, maturation from transient plasmablast to long-lived ASCs in bone marrow is predicated on quantitative increases in Blimp-1 expression.
- Published
- 2004
- Full Text
- View/download PDF
41. Oct-2 regulates CD36 gene expression via a consensus octamer, which excludes the co-activator OBF-1.
- Author
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Shore P, Dietrich W, and Corcoran LM
- Subjects
- Animals, Base Sequence, CD36 Antigens biosynthesis, Cell Line, Cells, Cultured, Cloning, Molecular, Consensus Sequence, Genes, Reporter, Host Cell Factor C1, Humans, Mice, Octamer Transcription Factor-1, Octamer Transcription Factor-2, RNA, Messenger biosynthesis, Sequence Alignment, B-Lymphocytes metabolism, CD36 Antigens genetics, DNA-Binding Proteins metabolism, Trans-Activators metabolism, Transcription Factors metabolism, Transcriptional Activation
- Abstract
The POU domain transcription factor, Oct-2, is essential for the B cell-specific expression of CD36 in mouse B cells. In order to determine how Oct-2 mediates expression of CD36 in B cells, we cloned and analysed the mouse CD36 promoter. In contrast to the human CD36 promoter, the mouse promoter contains a consensus octamer element of the type ATGCTAAT. This octamer element can be bound by either Oct-1 or Oct-2 but requires the expression of Oct-2 to activate transcription in B cells. Mutation of the octamer element renders the CD36 promoter refractory to activation by Oct-2. Furthermore, we demonstrate that the CD36 octamer element does not support recruitment of the B cell-specific co-activator OBF-1 and that CD36 expression is unaffected in primary B cells derived from obf-1(-/-) mice. We conclude that Oct-2 activates CD36 gene expression in mouse B cells via the octamer element in the promoter. Our data also demonstrate that CD36 is the first example of an Oct-2-dependent gene whose expression in B cells is independent of OBF-1. These findings support the notion that Oct-2 regulates gene transcription by both OBF-1-dependent and -independent mechanisms.
- Published
- 2002
- Full Text
- View/download PDF
42. Continued differentiation during B lymphopoiesis requires signals in addition to cell survival.
- Author
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Tarlinton DM, Corcoran LM, and Strasser A
- Subjects
- Animals, Base Sequence, Cell Differentiation, Cell Division, Cell Survival, DNA genetics, DNA-Binding Proteins genetics, DNA-Binding Proteins immunology, Female, Gene Rearrangement, B-Lymphocyte, Hematopoietic Stem Cells cytology, Hematopoietic Stem Cells immunology, Immunoglobulin D genetics, Immunoglobulin D immunology, Immunoglobulin M genetics, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Mice, SCID, Mice, Transgenic, Molecular Sequence Data, Proto-Oncogene Proteins c-bcl-2 genetics, Proto-Oncogene Proteins c-bcl-2 immunology, Signal Transduction, B-Lymphocytes cytology, B-Lymphocytes immunology, Homeodomain Proteins
- Abstract
During B lymphopoiesis, cells undergo successive rounds of division and growth arrest coupled to intermittent selection on the basis of Ig expression. It is unresolved whether differentiation requires specific signaling or is merely the consequence of sustained cell survival. Transgenic expression of the cell death antagonist, Bcl-2, promoted accumulation of B lymphoid cells in mice deficient in antigen receptor rearrangement (scid or rag-1-/-) and in mice lacking the IgM transmembrane domain (microMT). Continued differentiation occurred, however, only in the bcl-2/scid and bcl-2/microMT mice. The appearance of B lineage cells expressing CD21, CD22 and CD23 was associated with DHJH rearrangements which encode a truncated C mu-containing protein called D mu in bcl-2/scid mice and with expression of Ig heavy chain classes other than IgM in the bcl-2/ microMT mice. In neither case, however, were proliferating cells observed in the more mature B lineage compartments in the bone marrow. Thus, continued B cell development requires signaling via Ig heavy chain-containing receptors and is not simply a consequence of blocking apoptosis.
- Published
- 1997
- Full Text
- View/download PDF
43. Bcl-2 can rescue T lymphocyte development in interleukin-7 receptor-deficient mice but not in mutant rag-1-/- mice.
- Author
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Maraskovsky E, O'Reilly LA, Teepe M, Corcoran LM, Peschon JJ, and Strasser A
- Subjects
- Animals, Antigens pharmacology, Antigens, CD metabolism, Apoptosis immunology, CD4-Positive T-Lymphocytes cytology, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes cytology, CD8-Positive T-Lymphocytes immunology, Cell Differentiation drug effects, Cell Differentiation genetics, Cell Differentiation immunology, Cells, Cultured, Gene Expression immunology, Genes, RAG-1 genetics, Humans, Interleukin-7 deficiency, Interleukin-7 genetics, Lymph Nodes cytology, Mice, Mice, Inbred C57BL, Mice, Transgenic, Mitogens pharmacology, Mutagenesis immunology, Receptors, Interleukin metabolism, Receptors, Interleukin-7, Signal Transduction immunology, Spleen cytology, Stem Cells chemistry, Stem Cells immunology, Thymus Gland cytology, Transgenes immunology, Antigens, CD genetics, CD4-Positive T-Lymphocytes chemistry, CD8-Positive T-Lymphocytes chemistry, DNA-Binding Proteins genetics, Homeodomain Proteins, Proto-Oncogene Proteins c-bcl-2 genetics, Receptors, Interleukin genetics
- Abstract
Signals from cytokine and antigen receptors play crucial roles during lymphocyte development. Mice lacking interleukin-7 receptor are lymphopenic, due to a defect in cell expansion at an early stage of differentiation, and the few mature T cells that develop in IL-7R-/- animals are functionally impaired. Both defects were rescued completely by overexpression of the anti-apoptosis protein Bcl-2. T cell progenitors lacking antigen receptor molecules are also blocked in differentiation and die, presumably because they fail to receive a positive signal via their pre-T cell receptor. Surprisingly, Bcl-2 did not promote survival or differentiation of T cells in rag-1-/- mice. These results provide evidence that blocking apoptosis is the essential function of IL-7R during differentiation and activation of T lymphocytes and that pre-TCR signaling blocks a pathway to apoptosis that is insensitive to Bcl-2.
- Published
- 1997
- Full Text
- View/download PDF
44. Identification of CD36 as the first gene dependent on the B-cell differentiation factor Oct-2.
- Author
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König H, Pfisterer P, Corcoran LM, and Wirth T
- Subjects
- Animals, B-Lymphocytes cytology, B-Lymphocytes drug effects, Base Sequence, CD36 Antigens, Cell Line, DNA Primers, Estradiol pharmacology, Macrophages metabolism, Mice, Mice, Mutant Strains, Molecular Sequence Data, Octamer Transcription Factor-2, RNA, Messenger isolation & purification, RNA, Messenger metabolism, Transcription Factors metabolism, Transcription, Genetic, Antigens, CD biosynthesis, B-Lymphocytes metabolism, DNA-Binding Proteins metabolism, Gene Expression Regulation
- Abstract
The Oct-2 transcription factor is expressed predominantly in B lymphocytes and has been shown previously to be important for the terminal phase of B-cell differentiation in mice. A number of genes specifically expressed in B cells contain Oct-2-binding sites in their regulatory regions. However, the analysis of expression levels of these genes in Oct-2-deficient B cells revealed that they were unaffected. Hence, there were no genes known that critically depend on Oct-2 for their expression. To understand the molecular basis for the Oct-2 effect on B-cell development, we searched for Oct-2 target genes by subtractive cDNA cloning. We show here that expression of the murine CD36 gene in B cells and macrophages requires a functional Oct-2 protein. Nuclear run-on experiments demonstrate that this gene is regulated transcriptionally by Oct-2. Moreover, CD36 levels correlated with the levels of Oct-2 expression in several mouse B-cell and macrophage cell lines. Finally, compared to wild-type and heterozygous mice, CD36 mRNA levels were markedly reduced in spleens and B-cell-enriched splenocyte fractions from oct-2-/- mice. The data identify CD36 as the first target gene critically dependent on Oct-2 for its expression. Because CD36 expression is also dependent on Oct-2 in vivo, it is a candidate gene through which Oct-2 could affect B-cell differentiation.
- Published
- 1995
- Full Text
- View/download PDF
45. Functional immunoglobulin transgenes guide ordered B-cell differentiation in Rag-1-deficient mice.
- Author
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Spanopoulou E, Roman CA, Corcoran LM, Schlissel MS, Silver DP, Nemazee D, Nussenzweig MC, Shinton SA, Hardy RR, and Baltimore D
- Subjects
- Animals, B-Lymphocytes cytology, Bone Marrow Cells, Cell Differentiation, Clonal Deletion, Gene Rearrangement, B-Lymphocyte, Gene Targeting, Genetic Complementation Test, H-2 Antigens immunology, Immunoglobulin kappa-Chains genetics, Immunoglobulin mu-Chains genetics, Mice, Mice, Inbred C57BL, Mice, Transgenic, Proteins genetics, T-Lymphocytes immunology, B-Lymphocytes immunology, Genes, Immunoglobulin, Genes, RAG-1, Homeodomain Proteins, Proteins physiology, Receptors, Antigen, B-Cell genetics
- Abstract
We have examined the regulatory role of the individual components of the immunoglobulin antigen receptor in B-cell development by transgenic complementation of Rag-1 deficient (Rag-1-) mice. Complementation with a membrane mu heavy chain (mu HC) gene allows progression of developmentally arrested Rag-1- pro-B-cells to the small pre-B cell stage, whereas the introduction of independently integrated mu HC and kappa light chain (kappa LC) transgenes promotes the appearance of peripheral lymphocytes which, however, remain unresponsive to external stimuli. Complete reconstitution of the B-cell lineage and the emergence of functionally nature Rag-1- peripheral B cells is achieved by the introduction of cointegrated heavy and light chain transgenes encoding an anti-H-2k antibody. This experimental system demonstrates the competence of the mu HC and kappa LC to direct and regulate the sequential stages of B-cell differentiation, defines the time at which negative selection of self-reactive B cells occurs, and shows that elimination of these cells occurs equally well in the absence of Rag-1 as in its presence. These data also support the hypothesis that Rag-1 directly participates in the V(D)J recombination process.
- Published
- 1994
- Full Text
- View/download PDF
46. Differential transactivation potential of Oct1 and Oct2 is determined by additional B cell-specific activities.
- Author
-
Pfisterer P, Annweiler A, Ullmer C, Corcoran LM, and Wirth T
- Subjects
- Animals, Enhancer Elements, Genetic genetics, Host Cell Factor C1, Mice, Octamer Transcription Factor-1, Octamer Transcription Factor-2, Promoter Regions, Genetic genetics, Protein Binding, Transfection, B-Lymphocytes physiology, DNA-Binding Proteins metabolism, Transcription Factors metabolism, Transcriptional Activation
- Abstract
Cell type-specific transcriptional regulation is generally believed to be mediated by sequence-specific transcription factors that are specifically present in the corresponding cells. The interaction of the lymphoid-specific Oct2 transcription factor has been thought to be responsible for the B cell-specific activity of octamer-containing promoter and enhancer elements. Here we show that physiological concentrations of Oct2 do not suffice to generate octamer-dependent promoter activity in non-B cell lines. Furthermore, we have tested the activity of octamer-dependent promoter and enhancer elements in B cell lines that lack the endogenous Oct2 protein. Our results demonstrate that in these Oct2-deficient B cells the ubiquitous endogenous Oct1 protein is able to stimulate octamer-containing promoters to a level comparable with that of normal Oct2-positive B cells. However, reporter constructs bearing the octamer motif in a distal enhancer position are not stimulated by the Oct1 protein, but do require the presence of Oct2. The B cell-specific octamer-dependent promoter activity mediated by Oct1 correlates with the presence of a novel B cell-specific octamer-binding complex containing the Oct1 protein. From these results we conclude that B cells contain two different activities: one that interacts with both Oct1 and Oct2 and mediates promoter proximal activity of the octamer motif and a second that specifically interacts with Oct2 to confer function from a remote enhancer position.
- Published
- 1994
- Full Text
- View/download PDF
47. Bcl-2 expression promotes B- but not T-lymphoid development in scid mice.
- Author
-
Strasser A, Harris AW, Corcoran LM, and Cory S
- Subjects
- Animals, Antigens, Differentiation biosynthesis, Base Sequence, Bone Marrow Cells, Cell Differentiation, Cell Survival, Cells, Cultured, DNA Primers, Immunophenotyping, Mice, Mice, SCID, Mice, Transgenic, Molecular Sequence Data, Proto-Oncogene Proteins genetics, Proto-Oncogene Proteins c-bcl-2, Receptors, Antigen, B-Cell biosynthesis, Receptors, Antigen, T-Cell biosynthesis, Spleen cytology, B-Lymphocytes cytology, Proto-Oncogene Proteins biosynthesis, T-Lymphocytes cytology
- Abstract
Expression of antigen receptors is vital for the development of B and T lymphocytes. In mice with the scid mutation, which are unable to make productive rearrangements of their immunoglobulin and T-cell receptor (TCR) genes, lymphopoiesis aborts at an early stage. The death of the immature lymphocytes by apoptosis is postulated to result from a failure to receive a survival signal induced by receptor engagement. Consistent with this hypothesis, introduction of immunoglobulin or TCR transgenes into scid mice promoted an increase in B- or T-lymphoid cells, respectively. As the protein encoded by the bcl-2 gene can inhibit cell death, we tested whether lymphopoiesis could be rescued in scid mice by crossing in a bcl-2 transgene. Strikingly, the bcl-2/scid mice accumulated almost normal numbers of B-lymphoid cells which lacked surface immunoglobulin but expressed markers of maturity. T-cell development remained blocked. Introducing a TCR transgene enabled bcl-2/scid mice to develop normal numbers of CD4+8+ thymocytes even in the absence of immunological selection, suggesting that T cells become competent to respond to bcl-2 protein only after the TCR complex is displayed at the cell surface.
- Published
- 1994
- Full Text
- View/download PDF
48. Oct-2, although not required for early B-cell development, is critical for later B-cell maturation and for postnatal survival.
- Author
-
Corcoran LM, Karvelas M, Nossal GJ, Ye ZS, Jacks T, and Baltimore D
- Subjects
- Animals, Antibody Formation genetics, Cell Differentiation genetics, DNA-Binding Proteins genetics, Flow Cytometry, Gene Expression Regulation, Genes, Homeobox, Lymphocyte Activation, Mice, Mutagenesis, Site-Directed, Octamer Transcription Factor-2, Protein Binding, Transfection, B-Lymphocytes physiology, DNA-Binding Proteins physiology, Gene Rearrangement, B-Lymphocyte, Genes, Immunoglobulin, Transcription Factors genetics
- Abstract
Oct-2, a POU homeo domain transcription factor, is believed to stimulate B-cell-restricted expression of immunoglobulin genes through binding sites in immunoglobulin gene promoters and enhancers. To determine whether Oct-2 is required for B-cell development or function, or has other developmental roles, the gene was disrupted by homologous recombination. Oct-2-l- mice develop normally but die within hours of birth for undetermined reasons. Mutants contain normal numbers of B-cell precursors but are somewhat deficient in IgM+ B cells. These B cells have a marked defect in their capacity to secrete immunoglobulin upon mitogenic stimulation in vitro. Thus, Oct-2 is not required for the generation of immunoglobulin-bearing B cells but is crucial for their maturation to immunoglobulin-secreting cells and for another undetermined organismal function.
- Published
- 1993
- Full Text
- View/download PDF
49. Virus-transformed pre-B cells show ordered activation but not inactivation of immunoglobulin gene rearrangement and transcription.
- Author
-
Schlissel MS, Corcoran LM, and Baltimore D
- Subjects
- Animals, Base Sequence, Cell Line, Humans, Immunoglobulin Constant Regions genetics, Immunoglobulin Joining Region genetics, Immunoglobulin Variable Region genetics, Molecular Sequence Data, Oligonucleotide Probes, Polymerase Chain Reaction, Abelson murine leukemia virus genetics, Cell Transformation, Viral, Gene Rearrangement, Genes, Immunoglobulin, Immunoglobulin Heavy Chains genetics, Immunoglobulin Light Chains genetics, Transcription, Genetic
- Abstract
Virus-transformed pre-B cells undergo ordered immunoglobulin (Ig) gene rearrangements during culture. We devised a series of highly sensitive polymerase chain reaction assays for Ig gene rearrangement and unrearranged Ig gene segment transcription to study both the possible relationship between these processes in cultured pre-B cells and the role played by heavy (H) chain (mu) protein in regulating gene rearrangement. Our analysis of pre-B cell cultures representing various stages of maturity revealed that transcription of each germline Ig locus precedes or is coincident with its rearrangement. Cell lines containing one functional rearranged H chain allele, however, continue to transcribe and to rearrange the allelic, unrearranged H chain locus. These cell lines appear to initiate but not terminate rearrangement events and therefore provide information about the requirements for activating rearrangement but not about allelic exclusion mechanisms.
- Published
- 1991
- Full Text
- View/download PDF
50. Genetic analysis of the human malaria parasite Plasmodium falciparum.
- Author
-
Walliker D, Quakyi IA, Wellems TE, McCutchan TF, Szarfman A, London WT, Corcoran LM, Burkot TR, and Carter R
- Subjects
- Adenosine Deaminase genetics, Animals, Anopheles parasitology, Antigens, Protozoan genetics, Chromosomes, Clone Cells, Crosses, Genetic, Insect Vectors, Malaria parasitology, Pan troglodytes, Pyrimethamine pharmacology, Recombination, Genetic, Plasmodium falciparum genetics
- Abstract
Malaria parasites are haploid for most of their life cycle, with zygote formation and meiosis occurring during the mosquito phase of development. The parasites can be analyzed genetically by transmitting mixtures of cloned parasites through mosquitoes to permit cross-fertilization of gametes to occur. A cross was made between two clones of Plasmodium falciparum differing in enzymes, drug sensitivity, antigens, and chromosome patterns. Parasites showing recombination between the parent clone markers were detected at a high frequency. Novel forms of certain chromosomes, detected by pulsed-field gradient gel electrophoresis, were produced readily, showing that extensive rearrangements occur in the parasite genome after cross-fertilization. Since patients are frequently infected with mixtures of genetically distinct parasites, mosquito transmission is likely to provide the principal mechanisms for generating parasites with novel genotypes.
- Published
- 1987
- Full Text
- View/download PDF
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