35 results on '"Marco Lepore"'
Search Results
2. Selection of phage-displayed human antibody fragments specific for CD1b presenting the Mycobacterium tuberculosis glycolipid Ac2SGL
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Frank Camacho, María E Sarmiento, Fatima Reyes, Louise Kim, Jim Huggett, Marco Lepore, Oscar Otero, Martine Gilleron, Germain Puzo, Mohd Nor Norazmi, Graham Rook, Lucia Mori, Gennaro De Libero, and Armando Acosta
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Antibodies ,CD1b ,Lipids ,Tuberculosis ,Microbiology ,QR1-502 - Abstract
Objective/background: The development of new tools capable of targeting Mycobacterium tuberculosis (Mtb)-infected cells have potential applications in diagnosis, treatment, and prevention of tuberculosis. In Mtb-infected cells, CD1b molecules present Mtb lipids to the immune system (Mtb lipid–CD1b complexes). Because of the lack of CD1b polymorphism, specific Mtb lipid–CD1b complexes could be considered as universal Mtb infection markers. 2-Stearoyl-3-hydroxyphthioceranoyl-2′-sulfate-α-α′-d-trehalose (Ac2SGL) is specific for Mtb, and is not present in other mycobacterial species. The CD1b–Ac2SGL complexes are expressed on the surface of human cells infected with Mtb. The aim of this study was to generate ligands capable of binding these CD1b–Ac2SGL complexes. Methods: A synthetic human scFv phage antibody library was used to select phage-displayed antibody fragments that recognized CD1b–Ac2SGL using CD1b-transfected THP-1 cells loaded with Ac2SGL. Results: One clone, D11—a single, light-variable domain (kappa) antibody (dAbκ11)—showed high relative binding to the Ac2SGL–CD1b complex. Conclusion: A ligand recognizing the Ac2SGL–CD1b complex was obtained, which is a potential candidate to be further tested for diagnostic and therapeutic applications.
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- 2016
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3. The Conventional Nature of Non-MHC-Restricted T Cells
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Marco Lepore, Lucia Mori, and Gennaro De Libero
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CD1 ,MR1 ,lipid antigens ,immunotherapy ,vaccines ,Immunologic diseases. Allergy ,RC581-607 - Abstract
The definition “unconventional T cells” identifies T lymphocytes that recognize non-peptide antigens presented by monomorphic antigen-presenting molecules. Two cell populations recognize lipid antigens and small metabolites presented by CD1 and MR1 molecules, respectively. A third cell population expressing the TCR Vγ9Vδ2 is stimulated by small phosphorylated metabolites. In the recent past, we have learnt a lot about the selection, tissue distribution, gene transcription programs, mode of expansion after antigen recognition, and persistence of these cells. These studies depict their functions in immune homeostasis and diseases. Current investigations are revealing that unconventional T cells include distinct sub-populations, which display unexpected similarities to classical MHC-restricted T cells in terms of TCR repertoire diversity, antigen specificity variety, functional heterogeneity, and naïve-to-memory differentiation dynamic. This review discusses the latest findings with a particular emphasis on these T cells, which appear to be more conventional than previously appreciated, and with the perspective of using CD1 and MR1-restricted T cells in vaccination and immunotherapy.
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- 2018
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4. Correction: Functionally diverse human T cells recognize non-microbial antigens presented by MR1
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Marco Lepore, Artem Kalinichenko, Salvatore Calogero, Pavanish Kumar, Bhairav Paleja, Mathias Schmaler, Vipin Narang, Francesca Zolezzi, Michael Poidinger, Lucia Mori, and Gennaro De Libero
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Medicine ,Science ,Biology (General) ,QH301-705.5 - Published
- 2017
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5. Functionally diverse human T cells recognize non-microbial antigens presented by MR1
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Marco Lepore, Artem Kalinichenko, Salvatore Calogero, Pavanish Kumar, Bhairav Paleja, Mathias Schmaler, Vipin Narang, Francesca Zolezzi, Michael Poidinger, Lucia Mori, and Gennaro De Libero
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MR1 ,T cell ,antigen recognition ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
MHC class I-related molecule MR1 presents riboflavin- and folate-related metabolites to mucosal-associated invariant T cells, but it is unknown whether MR1 can present alternative antigens to other T cell lineages. In healthy individuals we identified MR1-restricted T cells (named MR1T cells) displaying diverse TCRs and reacting to MR1-expressing cells in the absence of microbial ligands. Analysis of MR1T cell clones revealed specificity for distinct cell-derived antigens and alternative transcriptional strategies for metabolic programming, cell cycle control and functional polarization following antigen stimulation. Phenotypic and functional characterization of MR1T cell clones showed multiple chemokine receptor expression profiles and secretion of diverse effector molecules, suggesting functional heterogeneity. Accordingly, MR1T cells exhibited distinct T helper-like capacities upon MR1-dependent recognition of target cells expressing physiological levels of surface MR1. These data extend the role of MR1 beyond microbial antigen presentation and indicate MR1T cells are a normal part of the human T cell repertoire.
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- 2017
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6. Extraction and Identification of T Cell Stimulatory Self-lipid Antigens
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Marco Lepore, Sebastiano Sansano, Claudia Lalla, Giulia Casorati, Gennaro Libero, and Lucia Mori
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Biology (General) ,QH301-705.5 - Abstract
Autoreactive T cells restricted to CD1 molecules and specific for endogenous lipids are abundant in human blood (de Jong et al., 2010; de Lalla et al., 2011). A few self-lipid molecules recognized by diverse individual T cell clones and accumulated within APCs following stress signals or cell transformation have been identified so far (de Jong et al., 2010; Chang et al., 2008; Lepore et al., 2014). These findings suggested that auto-reactive CD1-restricted T cells display broad lipid specificities and may play critical roles in different types of immune responses including cancer immune surveillance, autoimmunity and antimicrobial immunity. Therefore, the identification of the repertoire of self-lipid molecules recognized by T cells is important to study the physiologic functions of this T cell population and to assess their therapeutic potential (Lepore et al., 2014). Here we describe the protocol we established to isolate and identify endogenous lipids derived from leukemia cells, which stimulate specific autoreactive CD1c-restricted T lymphocytes (Lepore et al., 2014). This protocol can be applied to isolate lipid antigens from any type of target cells and to investigate the self-lipid antigen specificity of autoreactive T cells restricted to all CD1 isoforms (Facciotti et al., 2012).
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- 2015
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7. Nucleobase adduct-containing metabolites are MR1 ligands that stimulate self-reactive MR1T cells
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Alessandro Vacchini, Qinmei Yang, Andrew Chancellor, Julian Spagnuolo, Daniel Joss, Ove Øyås, Aisha Beshirova, Corinne De Gregorio, Michael Pfeffer, Jörg Stelling, Daniel Häussinger, Marco Lepore, Lucia Mori, and Gennaro De Libero
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SummaryMR1T lymphocytes are a recently identified population of T cells that recognize unknown self-antigens presented by the non-polymorphic MHC-I-related molecule, MR1. MR1T cells can kill tumor cells and modulate the functions of other immune cells with promising therapeutic applications. By integrating genetic, pharmacological and biochemical approaches we identified carbonyl stress and alterations of nucleobase metabolism in tumor target cells that promote recognition by MR1 T cells. We dissected these pathways and found that nucleobase adduct-containing metabolites are self-antigens stimulating MR1T cells. Several nucleobase adducts are presented by MR1 molecules and stimulate individual MR1T cells. Our data suggest that MR1T cells are surveyor of cellular metabolic alterations occurring in conditions of metabolic stress, such as cancer, and lay the groundwork for the development of novel HLA-unrestricted T cell-based therapies.
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- 2022
8. T cell receptor diversity, specificity and promiscuity of functionally heterogeneous human MR1-restricted T cells
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Deborah A. Lewinsohn, Marco Lepore, and David M. Lewinsohn
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Chemistry ,Ligand ,Receptors, Antigen, T-Cell, alpha-beta ,Histocompatibility Antigens Class I ,Immunology ,Cell ,T-cell receptor ,Receptors, Antigen, T-Cell ,MAIT Cells ,T-Cell Antigen Receptor Specificity ,Computational biology ,Small molecule ,Mucosal-Associated Invariant T Cells ,Article ,Minor Histocompatibility Antigens ,medicine.anatomical_structure ,Promiscuity ,Antigen ,T-Lymphocyte Subsets ,medicine ,Humans ,Immunity, Mucosal ,Molecular Biology ,Alpha chain - Abstract
The monomorphic MHC-class I-like molecule, MR1, presents small metabolites to T cells. MR1 is the restriction element for microbe-reactive mucosal-associated invariant T (MAIT) cells. MAIT cells have limited TCR usage, including a semi-invariant TCR alpha chain and express high levels of CD161 and CD26. In addition to microbial lumazine metabolites, recent studies have demonstrated that MR1 is able to capture a variety of diverse chemical entities including folate-derivatives, a number of drug-like and other synthetic small molecules, and as yet undefined compounds of self-origin. This capacity of MR1 to bind distinct ligands likely accounts for the recent identification of additional, non-canonical, subsets of MR1-restricted T (MR1T) cells. These subsets can be defined based on their ability to recognize diverse microbes as well as their reactivity to non-microbial cell-endogenous ligands, including tumor-associated antigens. Herein, we will discuss our current understanding of MR1T cell diversity in terms of TCR usage, ligand recognition and functional attributes (Table I).
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- 2021
9. Activation of TCR Vδ1+ and Vδ1−Vδ2− γδ T Cells upon Controlled Infection with Plasmodium falciparum in Tanzanian Volunteers
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Said Jongo, Jean-Pierre Dangy, Daniela Di Blasi, Stephen L. Hoffman, Marco Lepore, Claudia Daubenberger, B. Kim Lee Sim, Salim Abdulla, Tobias Rutishauser, Kamaka Ramadhani, Marcel Tanner, and Gennaro De Libero
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biology ,T cell ,Immunology ,T-cell receptor ,Plasmodium falciparum ,Parasitemia ,Human leukocyte antigen ,biology.organism_classification ,medicine.disease ,PfSPZ vaccine ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,medicine.anatomical_structure ,Antigen ,medicine ,Immunology and Allergy ,030215 immunology - Abstract
Our understanding of the human immune response to malaria remains incomplete. Clinical trials using whole-sporozoite-based vaccination approaches such as the Sanaria PfSPZ Vaccine, followed by controlled human malaria infection (CHMI) to assess vaccine efficacy offer a unique opportunity to study the immune response during Plasmodium falciparum infection. Diverse populations of T cells that are not restricted to classical HLA (unconventional T cells) participate in the host response during Plasmodium infection. Although several populations of unconventional T cells exist, the majority of studies focused on TCR Vγ9Vδ2 cells, the most abundant TCR γδ cell population in peripheral blood. In this study, we dissected the response of three TCR γδ cell subsets and mucosal-associated invariant T cells in healthy volunteers immunized with PfSPZ Vaccine and challenged by CHMI using Sanaria PfSPZ Challenge. Using a flow cytometry-based unbiased analysis followed by T cell cloning, several findings were made. Whereas major ex vivo alterations were not detectable after immunization with PfSPZ Vaccine, TCR Vδ2, and mucosal-associated invariant T cells expanded after asexual blood-stage parasitemia induced by CHMI. CHMI, but not vaccination, also induced the activation of TCR Vδ1 and Vδ1−Vδ2− γδ T cells. The activated TCR Vδ1 cells were oligoclonal, suggesting clonal expansion, and upon repeated CHMI, showed diminished response, indicating long-term alterations induced by blood-stage parasitemia. Some TCR Vδ1 clones recognized target cells in the absence of parasite-derived Ags, thus suggesting recognition of self-molecules. These findings reveal the articulate participation of different populations of unconventional T cells to P. falciparum infection.
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- 2020
10. Allosteric activation of T cell antigen receptor signaling by quaternary structure relaxation
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Nicla Porciello, Dheeraj Prakaash, Michael L. Dustin, Antreas C. Kalli, Oreste Acuto, Roberto Raggiaschi, Marco Lepore, Omer Dushek, Giulia Masi, Andre Cohnen, Deborah Cipria, Mark S.P. Sansom, Anna-Lisa Lanz, David K. Cole, Donatella Galgano, and Štefan Bálint
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T cell antigen receptor ,QH301-705.5 ,CD3 ,Allosteric regulation ,Receptors, Antigen, T-Cell ,Peptide ,chemical and pharmacologic phenomena ,02 engineering and technology ,Ligands ,General Biochemistry, Genetics and Molecular Biology ,Article ,Major Histocompatibility Complex ,03 medical and health sciences ,0302 clinical medicine ,Allosteric Regulation ,allosteric mechanism ,Humans ,Phosphorylation ,Biology (General) ,Protein Structure, Quaternary ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,biology ,T cell activation ,Correction ,T-cell Antigen ,adaptive immunity ,021001 nanoscience & nanotechnology ,Acquired immune system ,3. Good health ,Cell biology ,molecular dynamics simulation ,HEK293 Cells ,chemistry ,Solubility ,Gain of Function Mutation ,biology.protein ,Protein quaternary structure ,Protein Multimerization ,0210 nano-technology ,030217 neurology & neurosurgery ,Function (biology) ,membrane signalling ,Signal Transduction - Abstract
Summary The mechanism of T cell antigen receptor (TCR-CD3) signaling remains elusive. Here, we identify mutations in the transmembrane region of TCRβ or CD3ζ that augment peptide T cell antigen receptor (pMHC)-induced signaling not explicable by enhanced ligand binding, lateral diffusion, clustering, or co-receptor function. Using a biochemical assay and molecular dynamics simulation, we demonstrate that the gain-of-function mutations loosen the interaction between TCRαβ and CD3ζ. Similar to the activating mutations, pMHC binding reduces TCRαβ cohesion with CD3ζ. This event occurs prior to CD3ζ phosphorylation and at 0°C. Moreover, we demonstrate that soluble monovalent pMHC alone induces signaling and reduces TCRαβ cohesion with CD3ζ in membrane-bound or solubilised TCR-CD3. Our data provide compelling evidence that pMHC binding suffices to activate allosteric changes propagating from TCRαβ to the CD3 subunits, reconfiguring interchain transmembrane region interactions. These dynamic modifications could change the arrangement of TCR-CD3 boundary lipids to license CD3ζ phosphorylation and initiate signal propagation., Graphical abstract, Highlights • Mutations in TCRβ and CD3ζ TMRs that reduce their interaction augment signaling • pMHC and anti-CD3 binding to TCR-CD3 induce similar quaternary structure relaxation • Soluble monovalent pMHC alone signals and reduces TCRαβ cohesion with CD3ζ • Allosteric changes in TCR-CD3 dynamics instigate T cell activation, T cell antigen receptor is central in adaptive immunity; however, the mechanism that couples ligand binding and intracellular signaling is still controversial. Here, Lanz et al. have taken an interdisciplinary approach demonstrating that binding of soluble monovalent pMHC to TCR-CD3 allosterically reduces TCRαβ cohesion with CD3ζ and initiates signal transduction.
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- 2021
11. Novel TCR-based biologics: mobilising T cells to warm ‘cold’ tumours
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Marco Lepore, Bent K. Jakobsen, Rupert Kenefeck, Ita OKelly, David K. Cole, and Kate L. Lowe
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T-Lymphocytes ,T cell ,Receptors, Antigen, T-Cell ,Cancer therapy ,Immunotherapy, Adoptive ,Cell therapy ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,Antigens, Neoplasm ,Neoplasms ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Clinical efficacy ,Biological Products ,business.industry ,T-cell receptor ,Proteins ,General Medicine ,Clinical trial ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Cancer research ,Immunotherapy ,business ,Early phase ,Single-Chain Antibodies ,gp100 Melanoma Antigen ,030215 immunology - Abstract
Immunotherapeutic strategies have revolutionised cancer therapy in recent years, bringing meaningful improvements in outcomes for patients with previously intractable conditions. These successes have, however, been largely limited to certain types of liquid tumours and a small subset of solid tumours that are known to be particularly immunogenic. Broadening these advances across the majority of tumour indications, which are characterised by an immune-excluded, immune-deserted or immune-suppressed ('cold') phenotype, will require alternative approaches that are able to specifically address this unique biological environment. Several newer therapeutic modalities, including adoptive cell therapy and T cell redirecting bispecific molecules, are considered to hold particular promise and are being investigated in early phase clinical trials across various solid tumour indications. ImmTAC molecules are a novel class of T cell redirecting bispecific biologics that exploit TCR-based targeting of tumour cells; providing potent and highly specific access to the vast landscape of intracellular targets. The first of these reagents to reach the clinic, tebentafusp (IMCgp100), has generated demonstrable clinical efficacy in an immunologically cold solid tumour with a high unmet need. Here, we highlight the key elements of the ImmTAC platform that make it ideally positioned to overcome the cold tumour microenvironment in an off-the-shelf format.
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- 2019
12. Specificity of bispecific T cell receptors and antibodies targeting peptide-HLA
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Malkit Sami, Ben de Wet, Elizabeth A. Potter, Rory M. Crean, Katy A. Lloyd, Velupillai Srikannathasan, Nikolai Lissin, Milos Aleksic, Anitha Jeyanthan, Miriam Hock, David K. Cole, Peter Eamon Molloy, Pierre J. Rizkallah, Marco Lepore, Annelise Vuidepot, Christopher J. Holland, Brian Cameron, Thomas Blicher, Robert J. Pengelly, Christopher R. Pudney, Ross A. Robinson, Johanne M. Pentier, Thomas E. Spinner, Marc W. van der Kamp, Bent K. Jakobsen, Nathaniel Liddy, Paul J. Conroy, Stephen Harper, and Angharad Lloyd
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0301 basic medicine ,Models, Molecular ,Antibodies, Neoplasm ,medicine.medical_treatment ,T-Lymphocytes ,Antigen presentation ,Receptors, Antigen, T-Cell ,Human leukocyte antigen ,Molecular Dynamics Simulation ,Crystallography, X-Ray ,Epitope ,Cell Line ,03 medical and health sciences ,0302 clinical medicine ,Cancer immunotherapy ,Antibody Specificity ,Antigens, Neoplasm ,HLA Antigens ,Cell Line, Tumor ,Antibodies, Bispecific ,medicine ,Humans ,Amino Acid Sequence ,biology ,Effector ,Chemistry ,T-cell receptor ,Molecular Mimicry ,General Medicine ,Cell biology ,030104 developmental biology ,Structural biology ,030220 oncology & carcinogenesis ,biology.protein ,Indicators and Reagents ,Antibody ,Peptides ,Research Article - Abstract
Tumor-associated peptide-human leukocyte antigen complexes (pHLAs) represent the largest pool of cell surface-expressed cancer-specific epitopes, making them attractive targets for cancer therapies. Soluble bispecific molecules that incorporate an anti-CD3 effector function are being developed to redirect T cells against these targets using 2 different approaches. The first achieves pHLA recognition via affinity-enhanced versions of natural TCRs (e.g., immune-mobilizing monoclonal T cell receptors against cancer [ImmTAC] molecules), whereas the second harnesses an antibody-based format (TCR-mimic antibodies). For both classes of reagent, target specificity is vital, considering the vast universe of potential pHLA molecules that can be presented on healthy cells. Here, we made use of structural, biochemical, and computational approaches to investigate the molecular rules underpinning the reactivity patterns of pHLA-targeting bispecifics. We demonstrate that affinity-enhanced TCRs engage pHLA using a comparatively broad and balanced energetic footprint, with interactions distributed over several HLA and peptide side chains. As ImmTAC molecules, these TCRs also retained a greater degree of pHLA selectivity, with less off-target activity in cellular assays. Conversely, TCR-mimic antibodies tended to exhibit binding modes focused more toward hot spots on the HLA surface and exhibited a greater degree of crossreactivity. Our findings extend our understanding of the basic principles that underpin pHLA selectivity and exemplify a number of molecular approaches that can be used to probe the specificity of pHLA-targeting molecules, aiding the development of future reagents.
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- 2020
13. Protective efficacy of a lipid antigen vaccine in a guinea pig model of tuberculosis
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Jacques Prandi, Marco Lepore, Martine Gilleron, Simon Clark, Emilie Layre, Emma Rayner, Gerald Larrouy-Maumus, Ann Williams, Germain Puzo, Gennaro De Libero, Imperial College London, Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Public Health England [London], Experimental Immunology, University Hospital Basel [Basel], Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées
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0301 basic medicine ,Tuberculosis ,[SDV]Life Sciences [q-bio] ,Guinea Pigs ,Spleen ,Biology ,Guinea pig ,03 medical and health sciences ,0302 clinical medicine ,Adjuvants, Immunologic ,Antigen ,Immunity ,medicine ,Animals ,Tuberculosis Vaccines ,Lung ,ComputingMilieux_MISCELLANEOUS ,Antigens, Bacterial ,General Veterinary ,General Immunology and Microbiology ,Public Health, Environmental and Occupational Health ,Mycobacterium tuberculosis ,medicine.disease ,Virology ,Bacterial Load ,3. Good health ,Vaccination ,Disease Models, Animal ,Treatment Outcome ,030104 developmental biology ,Infectious Diseases ,medicine.anatomical_structure ,[SDV.IMM.IA]Life Sciences [q-bio]/Immunology/Adaptive immunology ,Immunization ,Liposomes ,Immunology ,[SDV.IMM]Life Sciences [q-bio]/Immunology ,Molecular Medicine ,Female ,lipids (amino acids, peptides, and proteins) ,Glycolipids ,BCG vaccine ,030215 immunology - Abstract
The bacillus Calmette Guerin (BCG) vaccine, the only licensed vaccine against TB, displays partial and variable efficacy, thus making the exploitation of novel vaccination strategies a major priority. Most of the current vaccines in pre-clinical or clinical development are based on the induction of T cells recognizing protein antigens. However, a large number of T cells specific for mycobacterial lipids are induced during infection, suggesting that lipid-based vaccines might represent an important component of novel sub-unit vaccines. Here, we investigated whether immunization with defined mycobacterial lipid antigens induces protection in guinea pigs challenged with M. tuberculosis. Two purified mycobacterial lipid antigens, the diacylated sulfoglycolipids (Ac2SGL) and the phosphatidyl-myo-inositol dimannosides (PIM2) were formulated in biophysically characterized liposomes made of dimethyl-dioctadecyl-ammonium (DDA) and synthetic trehalose 6,6'-dibehenate (TDB). In three protection trials, a reduction of bacterial load in the spleen of inoculated animals was consistently observed compared to the unvaccinated group. Moreover, a reduction in the number of lesions and severity of pathology was detected in the lungs and spleen of the lipid vaccine group compared to unvaccinated controls. As the degree of protection achieved is similar to that observed using protein antigens in the same guinea pig model, these promising results pave the way to future investigations of lipid antigens as subunit vaccines.
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- 2017
14. Activation of TCR Vδ1
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Tobias, Rutishauser, Marco, Lepore, Daniela, Di Blasi, Jean-Pierre, Dangy, Salim, Abdulla, Said, Jongo, Kamaka, Ramadhani, B Kim Lee, Sim, Stephen L, Hoffman, Marcel, Tanner, Claudia, Daubenberger, and Gennaro, De Libero
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Adult ,Male ,Young Adult ,Adolescent ,T-Lymphocyte Subsets ,Plasmodium falciparum ,Humans ,Receptors, Antigen, T-Cell, gamma-delta ,Malaria, Falciparum ,Single-Cell Analysis ,Tanzania ,Cells, Cultured ,Healthy Volunteers - Abstract
Our understanding of the human immune response to malaria remains incomplete. Clinical trials using whole-sporozoite-based vaccination approaches such as the Sanaria PfSPZ Vaccine, followed by controlled human malaria infection (CHMI) to assess vaccine efficacy offer a unique opportunity to study the immune response during
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- 2019
15. Interferon lambda 4 can directly activate human CD19+ B cells and CD8+ T cells
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Gennaro De Libero, Daniela Di Blasi, Marco Lepore, Julian Spagnuolo, Mairene Coto-Llerena, Luigi Terracciano, Markus H. Heim, Glenn R. Bantug, Aleksei Suslov, Diego Calabrese, and Francois H.T. Duong
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Male ,0301 basic medicine ,Health, Toxicology and Mutagenesis ,Blood Donors ,Hepacivirus ,Plant Science ,CD8-Positive T-Lymphocytes ,Lymphocyte Activation ,medicine.disease_cause ,0302 clinical medicine ,Interferon ,Cytotoxic T cell ,Receptor ,Research Articles ,Receptors, Interferon ,B-Lymphocytes ,Ecology ,medicine.diagnostic_test ,biology ,Chemistry ,food and beverages ,Middle Aged ,Hepatitis C ,Phenotype ,030220 oncology & carcinogenesis ,Female ,Research Article ,Signal Transduction ,medicine.drug ,Adult ,Adolescent ,Hepatitis C virus ,Antigens, CD19 ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,CD19 ,Flow cytometry ,Young Adult ,03 medical and health sciences ,medicine ,Humans ,Aged ,Interleukins ,fungi ,Interferon-alpha ,030104 developmental biology ,Cancer research ,biology.protein ,Interferons ,CD8 - Abstract
Direct effects of IFNλ4 on CD8+ T cells can link the IFNλ4 genotype to differential clearance of hepatitis C virus infections., Compared with the ubiquitous expression of type I (IFNα and IFNβ) interferon receptors, type III (IFNλ) interferon receptors are mainly expressed in epithelial cells of mucosal barriers of the of the intestine and respiratory tract. Consequently, IFNλs are important for innate pathogen defense in the lung and intestine. IFNλs also determine the outcome of hepatitis C virus (HCV) infections, with IFNλ4 inhibiting spontaneous clearance of HCV. Because viral clearance is dependent on T cells, we explored if IFNλs can directly bind to and regulate human T cells. We found that human B cells and CD8+ T cells express the IFNλ receptor and respond to IFNλs, including IFNλ4. IFNλs were not inhibitors but weak stimulators of B- and T-cell responses. Furthermore, IFNλ4 showed neither synergistic nor antagonistic effects in co-stimulatory experiments with IFNλ1 or IFNα. Multidimensional flow cytometry of cells from liver biopsies of hepatitis patients from IFNλ4-producers showed accumulation of activated CD8+ T cells with a central memory-like phenotype. In contrast, CD8+ T cells with a senescent/exhausted phenotype were more abundant in IFNλ4–non-producers. It remains to be elucidated how IFNλ4 promotes CD8 T-cell responses and inhibits the host immunity to HCV infections.
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- 2020
16. The Immunology of CD1- and MR1-Restricted T Cells
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Marco Lepore, Lucia Mori, and Gennaro De Libero
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0301 basic medicine ,Immunology ,Antigen presentation ,Receptors, Antigen, T-Cell ,Infections ,Lymphocyte Activation ,Major histocompatibility complex ,Autoimmune Diseases ,Antigens, CD1 ,Minor Histocompatibility Antigens ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,Neoplasms ,Animals ,Humans ,Immunology and Allergy ,Cytotoxic T cell ,IL-2 receptor ,Antigens ,Antigen-presenting cell ,Immunologic Surveillance ,Antigen Presentation ,biology ,Histocompatibility Antigens Class I ,Acquired immune system ,Natural killer T cell ,Cell biology ,Killer Cells, Natural ,030104 developmental biology ,biology.protein ,Natural Killer T-Cells ,Protein Binding ,030215 immunology - Abstract
CD1- and MHC-related molecule-1 (MR1)-restricted T lymphocytes recognize nonpeptidic antigens, such as lipids and small metabolites, and account for a major fraction of circulating and tissue-resident T cells. They represent a readily activated, long-lasting population of effector cells and contribute to the early phases of immune response, orchestrating the function of other cells. This review addresses the main aspects of their immunological functions, including antigen and T cell receptor repertoires, mechanisms of nonpeptidic antigen presentation, and the current evidence for their participation in human and experimental diseases.
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- 2016
17. Abstract 4554: Functionally distinct T cell subsets contribute to ImmTAC-mediated anti-tumor response
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Angela Valerio-Fernandes, Cheryl McAlpine, Christopher J. Holland, David Berman, Rahul C. Khanolkar, Mariantonella Vardeu, Marco Lepore, Sion Lewis, Rupert Kenefeck, Adel Benlahrech, and David K. Cole
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Cancer Research ,medicine.medical_treatment ,T cell ,T-cell receptor ,Human leukocyte antigen ,Biology ,Cytokine ,medicine.anatomical_structure ,Oncology ,Cancer cell ,biology.protein ,Cancer research ,medicine ,Cytotoxic T cell ,Antibody ,CD8 - Abstract
Introduction: Bispecific T cell engagers hold promise for effective cancer treatment. The anti-tumor activity of these therapeutics molecules predominantly relies on their capacity to induce direct killing of tumor cells by engaging the cytotoxic machinery of polyclonal CD8+ T cells. However, the impact of additional functionally different T cell populations that can be engaged alongside CD8+ T cells remains unclear. ImmTAC molecules are a novel class of bispecific fusion proteins that use an affinity-enhanced monoclonal TCR to target tumor antigen-derived peptides presented by HLA, and an anti-CD3 monomeric antibody to engage T cells. Tebentafusp, our lead clinical candidate, targets a gp100-derived peptide and is under clinical investigation in metastatic melanoma. Preliminary data revealed T cell activation, trafficking and infiltration into the tumor bed in patients responding to treatment. Importantly not only CD8+ T cells, but also different subsets of CD4+ T cells appeared to be activated, mobilized and redirected to the tumor site following tebentafusp treatment, suggesting a potential contribution of these T cell subsets to the anti-tumor response. The aim of this study was to investigate in vitro the functional capacity of different T cell populations, besides CD8+ T cells, following ImmTAC-mediated redirection toward cancer cells. Methods: Th1, Th2, Th17 CD4+ T cells, γδ T cells and Mucosal-Associated Invariant T cells (MAIT) were isolated from healthy volunteers and their functional response following exposure to ImmTAC in the presence of target cells was analysed. Results: In addition to CD8+ T cells, other T cell populations, were activated in vitro by ImmTAC and elicited a range of effector functions that may differentially contribute to anti-tumor responses. For example, we found that γδ T cells were able to mount rapid and potent cytokine and cytotoxic responses against cancer cells upon redirection with ImmTAC. The mechanisms that underpin our in vitro observations and the potential correlations in patients treated with tebentafusp are under investigation. Conclusions: Multiple T cells populations display functionally distinct responses following ImmTAC-mediated redirection. These results will add valuable insight to our understanding of bispecific T cell engager mechanism of action. In addition, they will help guide rationale for improving the design of these therapeutic molecules and select appropriate combination strategies. Citation Format: Adel Benlahrech, David K. Cole, Christopher J. Holland, Rupert Kenefeck, Rahul C. Khanolkar, Cheryl McAlpine, Sion Lewis, Angela Valerio-Fernandes, Mariantonella Vardeu, David Berman, Marco Lepore. Functionally distinct T cell subsets contribute to ImmTAC-mediated anti-tumor response [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4554.
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- 2020
18. Correction: Functionally diverse human T cells recognize non-microbial antigens presented by MR1
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Artem Kalinichenko, Bhairav Paleja, Lucia Mori, Salvatore Calogero, Michael Poidinger, Pavanish Kumar, Mathias Schmaler, Vipin Narang, Gennaro De Libero, Marco Lepore, and Francesca Zolezzi
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0301 basic medicine ,General Immunology and Microbiology ,QH301-705.5 ,Science ,General Neuroscience ,Immunology ,MR1 ,T cell ,General Medicine ,Biology ,General Biochemistry, Genetics and Molecular Biology ,antigen recognition ,03 medical and health sciences ,030104 developmental biology ,Antigen ,Medicine ,Biology (General) ,Research Article ,Human - Abstract
MHC class I-related molecule MR1 presents riboflavin- and folate-related metabolites to mucosal-associated invariant T cells, but it is unknown whether MR1 can present alternative antigens to other T cell lineages. In healthy individuals we identified MR1-restricted T cells (named MR1T cells) displaying diverse TCRs and reacting to MR1-expressing cells in the absence of microbial ligands. Analysis of MR1T cell clones revealed specificity for distinct cell-derived antigens and alternative transcriptional strategies for metabolic programming, cell cycle control and functional polarization following antigen stimulation. Phenotypic and functional characterization of MR1T cell clones showed multiple chemokine receptor expression profiles and secretion of diverse effector molecules, suggesting functional heterogeneity. Accordingly, MR1T cells exhibited distinct T helper-like capacities upon MR1-dependent recognition of target cells expressing physiological levels of surface MR1. These data extend the role of MR1 beyond microbial antigen presentation and indicate MR1T cells are a normal part of the human T cell repertoire. DOI: http://dx.doi.org/10.7554/eLife.24476.001, eLife digest White blood cells called T cells recognize germs and infected cells, and get rid of other cells in the body that look different to healthy cells – for example, tumor cells. These activities all depend on a molecule called the T cell receptor (or TCR for short), which is found on the surface of the T cells. Each TCR interacts with a specific complex on the surface of the target cell. One of the molecules recognized by the TCR is known as MHC class I-related (shortened to MR1). This molecule attracts TCRs to infected cells, but it was not know if the MR1 molecule could attract TCRs to cancer cells too. Lepore et al. now show that there are indeed T cells in humans that recognize cancer cells through interaction with the MR1 molecules produced by the cancer cells. This new group of T cells has been named MR1T, and the cells can be easily detected in the blood of healthy individuals. The cells can be classified as a new cell population based on their capacity to recognize MR1 and how they react with different types of cancer cells. Importantly, the MR1 that attracts these TCRs is the same in all people, and so the same TCR may recognize MR1-expressing cancer cells from different patients. The next challenge is to identify MR1T cells that recognize and kill cancer cells from different tissues. These studies will hopefully pave the way for new and broader strategies to combat cancer. DOI: http://dx.doi.org/10.7554/eLife.24476.002
- Published
- 2017
19. Functionally diverse human T cells recognize non-microbial antigens presented by MR1
- Author
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Salvatore Calogero, Marco Lepore, Gennaro De Libero, Bhairav Paleja, Vipin Narang, Francesca Zolezzi, Pavanish Kumar, Michael Poidinger, Lucia Mori, Mathias Schmaler, and Artem Kalinichenko
- Subjects
0301 basic medicine ,QH301-705.5 ,T-Lymphocytes ,T cell ,Science ,Immunology ,Antigen presentation ,CD1 ,Streptamer ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Minor Histocompatibility Antigens ,03 medical and health sciences ,0302 clinical medicine ,NK-92 ,medicine ,Humans ,Cytotoxic T cell ,Antigens ,Biology (General) ,Antigen-presenting cell ,Antigen Presentation ,General Immunology and Microbiology ,General Neuroscience ,Histocompatibility Antigens Class I ,MR1 ,Correction ,General Medicine ,Natural killer T cell ,3. Good health ,Cell biology ,antigen recognition ,030104 developmental biology ,medicine.anatomical_structure ,Cytokines ,Medicine ,Receptors, Chemokine ,030215 immunology - Abstract
White blood cells called T cells recognize germs and infected cells, and get rid of other cells in the body that look different to healthy cells – for example, tumor cells. These activities all depend on a molecule called the T cell receptor (or TCR for short), which is found on the surface of the T cells. Each TCR interacts with a specific complex on the surface of the target cell. One of the molecules recognized by the TCR is known as MHC class I-related (shortened to MR1). This molecule attracts TCRs to infected cells, but it was not know if the MR1 molecule could attract TCRs to cancer cells too. Lepore et al. now show that there are indeed T cells in humans that recognize cancer cells through interaction with the MR1 molecules produced by the cancer cells. This new group of T cells has been named MR1T, and the cells can be easily detected in the blood of healthy individuals. The cells can be classified as a new cell population based on their capacity to recognize MR1 and how they react with different types of cancer cells. Importantly, the MR1 that attracts these TCRs is the same in all people, and so the same TCR may recognize MR1-expressing cancer cells from different patients. The next challenge is to identify MR1T cells that recognize and kill cancer cells from different tissues. These studies will hopefully pave the way for new and broader strategies to combat cancer.
- Published
- 2017
20. Author response: Functionally diverse human T cells recognize non-microbial antigens presented by MR1
- Author
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Marco Lepore, Artem Kalinichenko, Salvatore Calogero, Pavanish Kumar, Bhairav Paleja, Mathias Schmaler, Vipin Narang, Francesca Zolezzi, Michael Poidinger, Lucia Mori, and Gennaro De Libero
- Published
- 2017
21. A novel self-lipid antigen targets human T cells against CD1c+ leukemias
- Author
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Paolo Dellabona, Heiko Gsellinger, Alessandra Forcina, Marco Lepore, Zhiyuan Li, S. Ramanjaneyulu Gundimeda, Gennaro De Libero, Michela Consonni, Daniela Montagna, Francesco M. Piccolo, Franco Locatelli, Chengfeng Xia, Claudio Garavaglia, Sebastiano Sansano, Paul Jenö, Andrea Scelfo, Claudia de Lalla, Fabio Ciceri, Daniel Häussinger, Guanghui Ni, Giulia Casorati, Attilio Bondanza, Chiara Bonini, Lucia Mori, Lepore, M, de Lalla, C, Gundimeda, Sr, Gsellinger, H, Consonni, M, Garavaglia, C, Sansano, S, Piccolo, F, Scelfo, A, Haussinger, D, Montagna, D, Locatelli, F, Bonini, MARIA CHIARA, Bondanza, Attilio, Forcina, A, Li, Zy, Ni, Gh, Ciceri, Fabio, Jeno, P, Xia, Cf, Mori, L, Dellabona, P, Casorati, G, and De Libero, G.
- Subjects
Male ,Adoptive cell transfer ,Adolescent ,T-Lymphocytes ,Immunology ,Biology ,Autoantigens ,Article ,Antigens, CD1 ,Jurkat Cells ,Mice ,NK-92 ,hemic and lymphatic diseases ,medicine ,Animals ,Humans ,Immunology and Allergy ,Cytotoxic T cell ,Child ,Antigen-presenting cell ,Immunologic Surveillance ,B cell ,Glycoproteins ,Antigen Presentation ,Acute leukemia ,Gene Expression Regulation, Leukemic ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,Natural killer T cell ,medicine.disease ,3. Good health ,Leukemia, Myeloid, Acute ,Leukemia ,medicine.anatomical_structure ,N/A ,Settore MED/38 - PEDIATRIA GENERALE E SPECIALISTICA ,Child, Preschool ,Female ,Lysophospholipids ,Blast Crisis - Abstract
CD1c self-reactive T cells recognize a novel class of self-lipids that are accumulated on leukemia cells., T cells that recognize self-lipids presented by CD1c are frequent in the peripheral blood of healthy individuals and kill transformed hematopoietic cells, but little is known about their antigen specificity and potential antileukemia effects. We report that CD1c self-reactive T cells recognize a novel class of self-lipids, identified as methyl-lysophosphatidic acids (mLPAs), which are accumulated in leukemia cells. Primary acute myeloid and B cell acute leukemia blasts express CD1 molecules. mLPA-specific T cells efficiently kill CD1c+ acute leukemia cells, poorly recognize nontransformed CD1c-expressing cells, and protect immunodeficient mice against CD1c+ human leukemia cells. The identification of immunogenic self-lipid antigens accumulated in leukemia cells and the observed leukemia control by lipid-specific T cells in vivo provide a new conceptual framework for leukemia immune surveillance and possible immunotherapy.
- Published
- 2014
22. Simplified Deoxypropionate Acyl Chains forMycobacterium tuberculosisSulfoglycolipid Analogues: Chain Length is Essential for High Antigenicity
- Author
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Marco Lepore, Germain Puzo, Jacques Prandi, Jean-Marie Beau, Aurélie Lemétais, Lucia Mori, Benjamin Gau, Gennaro De Libero, Yann Bourdreux, Luis F. Garcia-Alles, Martine Gilleron, University of Basel (Unibas), Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Experimental Immunology, University Hospital Basel [Basel], Institut de Chimie des Substances Naturelles (ICSN), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), and Centre National de la Recherche Scientifique (CNRS)
- Subjects
Antigenicity ,Biology ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Mycobacterium tuberculosis ,chemistry.chemical_compound ,Glycolipid ,Antigen ,Humans ,Tuberculosis ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Tuberculosis Vaccines ,Molecular Biology ,Antigens, Bacterial ,[CHIM.ORGA]Chemical Sciences/Organic chemistry ,010405 organic chemistry ,Organic Chemistry ,Trehalose ,biology.organism_classification ,3. Good health ,0104 chemical sciences ,Chain length ,chemistry ,Acyl chain ,Molecular Medicine ,lipids (amino acids, peptides, and proteins) ,Glycolipids - Abstract
International audience; The longer, the better: Increasing the lengths of the 1,3-methyl-branched fatty acyl chain units in mycobacterial diacylated sulfoglycolipid (Acyl2 SGL) analogues led to dramatic improvements in their antigenic properties and gave products more potent than the natural antigen Acyl2 SGLs.
- Published
- 2013
23. Total synthesis, stereochemical elucidation and biological evaluation of Ac2SGL; a 1,3-methyl branched sulfoglycolipid from Mycobacterium tuberculosis
- Author
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Marco Lepore, Danny Geerdink, Bjorn ter Horst, Martine Gilleron, Lucia Mori, Adriaan J. Minnaard, Germain Puzo, Gennaro De Libero, Anna K. H. Hirsch, Synthetic Organic Chemistry, and Stratingh Institute of Chemistry
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Cord factor ,biology ,SULFURYL IMIDAZOLIUM SALTS ,Stereochemistry ,HUMAN CD1B ,RECOGNITION ,Total synthesis ,General Chemistry ,CORD FACTOR ,biology.organism_classification ,STRAIN H37RV ,SULFOLIPID-I ,ALPHA ,Mycobacterium tuberculosis ,Sulfation ,Immune system ,Biochemistry ,Antigen ,VIRULENCE ,BIOSYNTHESIS ,ASYMMETRIC-SYNTHESIS ,Pathogen ,Function (biology) - Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), continues to represent a challenging pathogen causing many deaths. A reason for the persistence of this pathogen is the cell-envelope composition, which consists of long-tailed (glyco) lipids, involved in the modulation of the host immune response. Diacylated sulfoglycolipid Ac(2)SGL (1), found in the cell envelope, is a potent antigen that stimulates the immune response towards TB. This observation suggests the application of 1 as part of a vaccine. Here, we report the first asymmetric total synthesis of 1. Two approaches were developed for the synthesis of hydroxyphthioceranic acid (4), its polypropionate part, thereby establishing the absolute stereochemistry of the C17 hydroxyl function to be of (R)-configuration. Subsequently, 4 was regioselectively connected to the trehalose core and after selective sulfation and a final fourfold deprotection step, pure 1 was obtained. The identity of synthetic and natural 1 was confirmed by NMR and mass analysis, Furthermore, synthetic 1 shows identical biological function to 1 and activates CD1b-restricted and Ac(2)SGL-specific T cells that are highly sensitive to minimal structural modifications of 1 with the same potency. A modeling study is presented to point out the structural features of 1 that are important for binding to the antigen-presenting molecule CD1b and to the T-cell receptor.
- Published
- 2013
24. Lysosomal Lipases PLRP2 and LPLA2 Process Mycobacterial Multi-acylated Lipids and Generate T Cell Stimulatory Antigens
- Author
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James A. Shayman, Lucia Mori, Diane Cala-De Paepe, Martine Gilleron, Emilie Layre, Gennaro De Libero, Frédéric Carrière, Naila Mebarek, Germain Puzo, Stéphane Canaan, Marco Lepore, Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, University of Basel (Unibas), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), University of Michigan [Ann Arbor], University of Michigan System, Enzymologie interfaciale et de physiologie de la lipolyse (EIPL), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
0301 basic medicine ,Endosome ,Acylation ,T-Lymphocytes ,T cell ,[SDV]Life Sciences [q-bio] ,Clinical Biochemistry ,Antigen presentation ,CD1 ,Biology ,Lymphocyte Activation ,Biochemistry ,Cell Line ,Mycobacterium ,law.invention ,03 medical and health sciences ,Glycolipid ,Antigen ,law ,Drug Discovery ,medicine ,Humans ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Antigens ,Molecular Biology ,ComputingMilieux_MISCELLANEOUS ,Pharmacology ,Antigen Presentation ,030102 biochemistry & molecular biology ,Lipase ,Lipids ,Phospholipases A2 ,030104 developmental biology ,medicine.anatomical_structure ,Cell culture ,Recombinant DNA ,Molecular Medicine ,lipids (amino acids, peptides, and proteins) ,Lysosomes - Abstract
International audience; Complex antigens require processing within antigen-presenting cells (APCs) to form T cell stimulatory complexes with CD1 antigen-presenting molecules. It remains unknown whether lipids with multi-acylated moieties also necessitate digestion by lipases to become capable of binding CD1 molecules and stimulate T cells. Here, we show that the mycobacterial tetra-acylated glycolipid antigens phosphatidyl-myo-inositol mannosides (PIM) are digested to di-acylated forms by pancreatic lipase-related protein 2 (PLRP2) and lysosomal phospholipase A2 (LPLA2) within APCs. Recombinant PLRP2 and LPLA2 removed the sn1- and sn2-bound fatty acids from the PIM glycerol moiety, as revealed by mass spectrometry and nuclear magnetic resonance studies. PLRP2 or LPLA2 gene silencing in APCs abolished PIM presentation to T cells, thus revealing an essential role of both lipases in vivo. These findings show that endosomal lipases participate in lipid antigen presentation by processing lipid antigens and have a role in T cell immunity against mycobacteria.
- Published
- 2016
25. Selection of phage-displayed human antibody fragments specific for CD1b presenting the Mycobacterium tuberculosis glycolipid Ac2SGL
- Author
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Jim F. Huggett, Armando Acosta, Gennaro De Libero, Louise Kim, Oscar Otero, Lucia Mori, Graham A. W. Rook, Frank Camacho, Mohd Nor Norazmi, Germain Puzo, Fátima Reyes, Martine Gilleron, Maria E. Sarmiento, Marco Lepore, Universidad de Concepción [Chile], Universiti Sains Malaysia (USM), University College of London [London] (UCL), University of Basel (Unibas), Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées
- Subjects
0301 basic medicine ,Microbiology (medical) ,Tuberculosis ,lcsh:QR1-502 ,Gene Expression ,chemical and pharmacologic phenomena ,CD1b ,Antibodies ,lcsh:Microbiology ,Antigens, CD1 ,Mycobacterium tuberculosis ,03 medical and health sciences ,chemistry.chemical_compound ,Glycolipid ,Immune system ,Gene expression ,medicine ,Humans ,Bacteriophages ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,ComputingMilieux_MISCELLANEOUS ,biology ,respiratory system ,biology.organism_classification ,medicine.disease ,Antibodies, Bacterial ,Trehalose ,Molecular biology ,Lipids ,3. Good health ,030104 developmental biology ,Infectious Diseases ,chemistry ,biology.protein ,Glycolipids ,Antibody ,Single-Chain Antibodies - Abstract
Objective/background The development of new tools capable of targeting Mycobacterium tuberculosis (Mtb)-infected cells have potential applications in diagnosis, treatment, and prevention of tuberculosis. In Mtb-infected cells, CD1b molecules present Mtb lipids to the immune system (Mtb lipid–CD1b complexes). Because of the lack of CD1b polymorphism, specific Mtb lipid–CD1b complexes could be considered as universal Mtb infection markers. 2-Stearoyl-3-hydroxyphthioceranoyl-2′-sulfate-α-α′- d -trehalose (Ac 2 SGL) is specific for Mtb, and is not present in other mycobacterial species. The CD1b–Ac 2 SGL complexes are expressed on the surface of human cells infected with Mtb. The aim of this study was to generate ligands capable of binding these CD1b–Ac 2 SGL complexes. Methods A synthetic human scFv phage antibody library was used to select phage-displayed antibody fragments that recognized CD1b–Ac 2 SGL using CD1b-transfected THP-1 cells loaded with Ac 2 SGL. Results One clone, D11—a single, light-variable domain (kappa) antibody (dAbκ11)—showed high relative binding to the Ac 2 SGL–CD1b complex. Conclusion A ligand recognizing the Ac 2 SGL–CD1b complex was obtained, which is a potential candidate to be further tested for diagnostic and therapeutic applications.
- Published
- 2016
26. Extraction and Identification of T Cell Stimulatory Self-lipid Antigens
- Author
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Lucia Mori, Sebastiano Sansano, Marco Lepore, Gennaro De Libero, Paolo Dellabona, Claudia de Lalla, and Giulia Casorati
- Subjects
Chemistry ,Strategy and Management ,Mechanical Engineering ,Lymphocyte ,T cell ,Lipid antigen ,Extraction (chemistry) ,Metals and Alloys ,CD1 ,Industrial and Manufacturing Engineering ,medicine.anatomical_structure ,Biochemistry ,medicine ,Identification (biology) ,Pan-T antigens - Published
- 2015
27. Peroxisome proliferator-activated receptor α controls cellular cholesterol trafficking in macrophages
- Author
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Jean-Charles Fruchart, Bart Staels, Sophie Lestavel, A.L. Mutka, Marco Lepore, Véronique Clavey, Lionel Helin, Giulia Chinetti-Gbaguidi, Elina Ikonen, and E. Rigamonti
- Subjects
Vesicular Transport Proteins ,nuclear receptors ,Peroxisome proliferator-activated receptor ,030204 cardiovascular system & hematology ,Biochemistry ,cholesterol homeostasis ,0302 clinical medicine ,Endocrinology ,hemic and lymphatic diseases ,RNA, Small Interfering ,Cells, Cultured ,Progesterone ,chemistry.chemical_classification ,0303 health sciences ,Membrane Glycoproteins ,biology ,Reverse cholesterol transport ,Intracellular Signaling Peptides and Proteins ,Cell Differentiation ,Cell biology ,Lipoproteins, LDL ,Cholesterol ,lipids (amino acids, peptides, and proteins) ,Peroxisome proliferator-activated receptor alpha ,congenital, hereditary, and neonatal diseases and abnormalities ,QD415-436 ,Cholesterol 7 alpha-hydroxylase ,03 medical and health sciences ,Niemann-Pick C1 Protein ,Humans ,PPAR alpha ,RNA, Messenger ,Scavenger receptor ,Liver X receptor ,Glycoproteins ,030304 developmental biology ,Macrophages ,Cell Membrane ,nutritional and metabolic diseases ,Biological Transport ,Cell Biology ,Gene Expression Regulation ,chemistry ,ABCA1 ,biology.protein ,atherosclerosis ,NPC1 ,Carrier Proteins ,gene regulation - Abstract
The mobilization of cholesterol from intracellular pools to the plasma membrane is a determinant that governs its availability for efflux to extracellular acceptors. NPC1 and NPC2 are proteins localized in the late endosome and control cholesterol transport from the lysosome to the plasma membrane. Here, we report that NPC1 and NPC2 gene expression is induced by oxidized LDL (OxLDL) in human macrophages. Because OxLDLs contain natural activators of peroxisome proliferator-activated receptor alpha (PPARalpha), a fatty acid-activated nuclear receptor, the regulation of NPC1 and NPC2 by PPARalpha and the consequences on cholesterol trafficking were further studied. NPC1 and NPC2 expression is induced by synthetic PPARalpha ligands in human macrophages. Furthermore, PPARalpha activation leads to an enrichment of cholesterol in the plasma membrane. By contrast, incubation with progesterone, which blocks postlysosomal cholesterol trafficking, as well as NPC1 and NPC2 mRNA depletion using small interfering RNA, abolished ABCA1-dependent cholesterol efflux induced by PPARalpha activators. These observations identify a novel regulatory role for PPARalpha in the control of cholesterol availability for efflux that, associated with its ability to inhibit cholesterol esterification and to stimulate ABCA1 and scavenger receptor class B type I expression, may contribute to the stimulation of reverse cholesterol transport.
- Published
- 2005
28. Correction: Corrigendum: Parallel T-cell cloning and deep sequencing of human MAIT cells reveal stable oligoclonal TCRβ repertoire
- Author
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Marco Lepore, Alessia Colone, Bhairav Paleja, Artem Kalinichenko, Francesca Zolezzi, Andreas Tschumi, Bernett Lee, Gennaro De Libero, Amit Singhal, Luigi Terracciano, Michael Poidinger, Antonio Bertoletti, Peter Sander, Lucia Mori, Evan W. Newell, and Luca Quagliata
- Subjects
Cloning ,Genetics ,Multidisciplinary ,Repertoire ,MAIT Cells ,General Physics and Astronomy ,General Chemistry ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Deep sequencing ,T cell cloning - Abstract
Corrigendum: Parallel T-cell cloning and deep sequencing of human MAIT cells reveal stable oligoclonal TCRβ repertoire
- Published
- 2014
29. Parallel T-cell cloning and deep sequencing of human MAIT cells reveal stable oligoclonal TCRβ repertoire
- Author
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Artem Kalinicenko, Alessia Colone, Andreas Tschumi, Bhairav Paleja, Peter Sander, Marco Lepore, Francesca Zolezzi, Luigi Terracciano, Amit Singhal, Antonio Bertoletti, Gennaro De Libero, Lucia Mori, Luca Quagliata, Michael Poidinger, Bernett Lee, and Evan W. Newell
- Subjects
Adult ,Cell type ,Receptors, Antigen, T-Cell, alpha-beta ,T-Lymphocytes ,General Physics and Astronomy ,Mucosal associated invariant T cell ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Deep sequencing ,Young Adult ,Sequence Analysis, Protein ,T-Lymphocyte Subsets ,MHC class I ,Humans ,Cytotoxic T cell ,RNA, Messenger ,Gene Rearrangement, beta-Chain T-Cell Antigen Receptor ,Multidisciplinary ,Intracellular parasite ,T-cell receptor ,General Chemistry ,Molecular biology ,Genes, T-Cell Receptor beta ,biology.protein ,Bacterial antigen ,Genes, T-Cell Receptor alpha - Abstract
Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize conserved bacterial antigens derived from riboflavin precursors, presented by the non-polymorphic MHC class I-like molecule MR1. Here we show that human MAIT cells are remarkably oligoclonal in both the blood and liver, display high inter-individual homology and exhibit a restricted length CDR3β domain of the TCRVβ chain. We extend this analysis to a second sub-population of MAIT cells expressing a semi-invariant TCR conserved between individuals. Similar to 'conventional' MAIT cells, these lymphocytes react to riboflavin-synthesizing microbes in an MR1-restricted manner and infiltrate solid tissues. Both MAIT cell types release Th0, Th1 and Th2 cytokines, and sCD40L in response to bacterial infection, show cytotoxic capacity against infected cells and promote killing of intracellular bacteria, thus suggesting important protective and immunoregulatory functions of these lymphocytes.
- Published
- 2014
30. Phage display of functional αβ single-chain T-cell receptor molecules specific for CD1b:Ac₂SGL complexes from Mycobacterium tuberculosis-infected cells
- Author
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Frank, Camacho, Jim, Huggett, Louise, Kim, Juan F, Infante, Marco, Lepore, Viviana, Perez, María E, Sarmiento, Graham, Rook, and Armando, Acosta
- Subjects
Antigens, Bacterial ,Receptors, Antigen, T-Cell, alpha-beta ,Recombinant Fusion Proteins ,Mycobacterium tuberculosis ,Lymphocyte Activation ,Cell Line ,Antigens, CD1 ,Viral Proteins ,Proceedings ,Genes, T-Cell Receptor beta ,Humans ,Tuberculosis ,Glycolipids ,Cell Surface Display Techniques ,Lung ,Genes, T-Cell Receptor alpha ,Bacteriophage M13 - Abstract
The development of molecules specific for M. tuberculosis-infected cells has important implications, as these tools may facilitate understanding of the mechanisms regulating host pathogen interactions in vivo. In addition, development of new tools capable to targeting M. tuberculosis-infected cells may have potential applications to diagnosis, treatment, and prevention of tuberculosis (TB). Due to the lack of CD1b polymorphism, M. tuberculosis lipid-CD1b complexes could be considered as universal tuberculosis infection markers. The aim of the present study was to display on the PIII surface protein of m13 phage, a human αβ single-chain T-cell receptor molecule specific for CD1b:2-stearoyl-3-hydroxyphthioceranoyl-2´-sulfate-α-α´-D-trehalose (Ac2SGL) which is a complex presented by human cells infected with M. tuberculosis. The results showed the pIII fusion particle was successfully displayed on the phage surface. The study of the recognition of the recombinant phage in ELISA and immunohistochemistry showed the recognition of CD1b:Ac2SGL complexes and cells in human lung tissue from a tuberculosis patient respectively, suggesting the specific recognition of the lipid-CD1b complex.
- Published
- 2013
31. Peroxisome-derived lipids are self antigens that stimulate invariant natural killer T cells in the thymus
- Author
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Alessia Colone, Marco Lepore, G.S. Ramanjaneyulu, Amit Singhal, Magdalena Kistowska, Federica Facciotti, Marco Cavallari, Johannes Berger, Lucia Mori, Chengfeng Xia, Gennaro De Libero, Guanghui Ni, Sebastiano Sansano, Sonja Forss-Petter, Facciotti, F, Ramanjaneyulu, G, Lepore, M, Sansano, S, Cavallari, M, Kistowska, M, Forss-Petter, S, Ni, G, Colone, A, Singhal, A, Berger, J, Xia, C, Mori, L, and De Libero, G
- Subjects
Antigens, Differentiation, T-Lymphocyte ,Immunology ,Cell ,iNKT cells, lipids, peroxisomes, thymic antigens, thymic selection ,Caspase 3 ,Thymus Gland ,Biology ,Mice ,Antigen ,Antigens, CD ,medicine ,Peroxisomes ,Immunology and Allergy ,Animals ,Lectins, C-Type ,Self-Antigens ,Mice, Knockout ,Thymocytes ,Phosphatidylethanolamines ,Peroxisome ,Natural killer T cell ,Lipids ,medicine.anatomical_structure ,Biochemistry ,Apoptosis ,CD1D ,biology.protein ,Natural Killer T-Cells ,lipids (amino acids, peptides, and proteins) ,Interleukin-4 ,Antigens, CD1d ,Lysophospholipids - Abstract
The development and maturation of semi-invariant natural killer T cells (iNKT cells) rely on the recognition of self antigens presented by CD1d restriction molecules in thymus. The nature of the stimulatory thymic self lipids remains elusive. We isolated lipids from thymocytes and found that ether-bonded mono-alkyl glycerophosphates and the precursors and degradation products of plasmalogens stimulated iNKT cells. Synthetic analogs showed high potency in activating thymic and peripheral iNKT cells. Mice deficient in the peroxisomal enzyme glyceronephosphate O-acyltransferase (GNPAT), essential for the synthesis of ether lipids, had significant alteration of the thymic maturation of iNKT cells and fewer iNKT cells in both thymus and peripheral organs, which confirmed the role of ether-bonded lipids as iNKT cell antigens. Thus, peroxisome-derived lipids are nonredundant self antigens required for the generation of a full iNKT cell repertoire.
- Published
- 2012
32. Targeting leukemia by CD1c-restricted T cells specific for a novel lipid antigen
- Author
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Gennaro De Libero, Lucia Mori, Marco Lepore, Giulia Casorati, Paolo Dellabona, and Claudia de Lalla
- Subjects
Acute leukemia ,medicine.medical_treatment ,Immunology ,CD1 ,Immunotherapy ,Biology ,medicine.disease ,Molecular biology ,Leukemia ,Oncology ,Antigen ,hemic and lymphatic diseases ,medicine ,Immunology and Allergy ,Cytotoxic T cell ,Multiplex ligation-dependent probe amplification ,Antigen-presenting cell ,Author's View - Abstract
A subset of CD1c-restricted T lymphocytes exhibits strong reactivity against leukemia cells. These T cells recognize methyl-lysophosphatidic acid (mLPA), a novel lipid antigen produced by acute leukemia cells. Considering that CD1c-restricted T cells display efficacious anti-leukemia activities in a mouse model, this lipid antigen thus represents a novel target in the immunotherapy of hematological malignancies.
- Published
- 2014
33. Liver X receptor activation controls intracellular cholesterol trafficking and esterification in human macrophages
- Author
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Bart Staels, Mohamed Amine Bouhlel, E. Rigamonti, Sophie Lestavel, J.C. Fruchart, Stephanie Bultel, Giulia Chinetti-Gbaguidi, Véronique Clavey, Aino Mutka, Elina Ikonen, Marco Lepore, Coralie Fontaine, and Lionel Helin
- Subjects
Physiology ,Vesicular Transport Proteins ,Receptors, Cytoplasmic and Nuclear ,Cholesterol 7 alpha-hydroxylase ,Mice ,Niemann-Pick C1 Protein ,hemic and lymphatic diseases ,Animals ,Humans ,RNA, Small Interfering ,Receptor ,Liver X receptor ,Cells, Cultured ,Progesterone ,Glycoproteins ,Liver X Receptors ,Membrane Glycoproteins ,biology ,Macrophages ,Reverse cholesterol transport ,Cell Membrane ,Intracellular Signaling Peptides and Proteins ,nutritional and metabolic diseases ,Biological Transport ,Orphan Nuclear Receptors ,Cell biology ,DNA-Binding Proteins ,Mice, Inbred C57BL ,ATP Binding Cassette Transporter 1 ,Cholesterol ,ABCG1 ,Biochemistry ,ABCA1 ,ABCG4 ,biology.protein ,lipids (amino acids, peptides, and proteins) ,ATP-Binding Cassette Transporters ,Cholesterol Esters ,Cardiology and Cardiovascular Medicine ,Carrier Proteins ,Foam Cells - Abstract
Liver X receptors (LXRs) are nuclear receptors that regulate macrophage cholesterol efflux by inducing ATP-binding cassette transporter A1 (ABCA1) and ABCG1/ABCG4 gene expression. The Niemann-Pick C (NPC) proteins NPC1 and NPC2 are located in the late endosome, where they control cholesterol trafficking to the plasma membrane. The mobilization of cholesterol from intracellular pools to the plasma membrane is a determinant governing its availability for efflux to extracellular acceptors. Here we investigated the influence of LXR activation on intracellular cholesterol trafficking in primary human macrophages. Synthetic LXR activators increase the amount of free cholesterol in the plasma membrane by inducing NPC1 and NPC2 gene expression. Moreover, ABCA1-dependent cholesterol efflux induced by LXR activators was drastically decreased in the presence of progesterone, which blocks postlysosomal cholesterol trafficking, and reduced when NPC1 and NPC2 mRNA expression was depleted using small interfering RNA. The stimulation of cholesterol mobilization to the plasma membrane by LXRs led to a decrease in cholesteryl ester formation and Acyl–coenzyme A cholesterol acyltransferase-1 activity. These data indicate that LXR activation enhances cholesterol trafficking to the plasma membrane, where it becomes available for efflux, at the expense of esterification, thus contributing to the overall effects of LXR agonists in the control of macrophage cholesterol homeostasis.
- Published
- 2005
34. Nonclassical T Cells and Their Antigens in Tuberculosis
- Author
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Gennaro De Libero, Lucia Mori, Amit Singhal, and Marco Lepore
- Subjects
Antigen Presentation ,Immunity, Cellular ,biology ,T-Lymphocytes ,Antigen presentation ,CD1 ,MHC restriction ,Major histocompatibility complex ,General Biochemistry, Genetics and Molecular Biology ,Immune system ,Biochemistry ,Antigen ,MHC class I ,biology.protein ,Humans ,Tuberculosis ,Antigens ,Pan-T antigens ,Perspectives - Abstract
T cells that recognize nonpeptidic antigens, and thereby are identified as nonclassical, represent important yet poorly characterized effectors of the immune response. They are present in large numbers in circulating blood and tissues and are as abundant as T cells recognizing peptide antigens. Nonclassical T cells exert multiple functions including immunoregulation, tumor control, and protection against infections. They recognize complexes of nonpeptidic antigens such as lipid and glycolipid molecules, vitamin B2 precursors, and phosphorylated metabolites of the mevalonate pathway. Each of these antigens is presented by antigen-presenting molecules other than major histocompatibility complex (MHC), including CD1, MHC class I–related molecule 1 (MR1), and butyrophilin 3A1 (BTN3A1) molecules. Here, we discuss how nonclassical T cells participate in the recognition of mycobacterial antigens and in the mycobacterial-specific immune response.
- Published
- 2014
35. Phage display of functional αβ single-chain T-cell receptor molecules specific for CD1b:Ac2SGL complexes from Mycobacterium tuberculosis-infected cells
- Author
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Marco Lepore, Armando Acosta, Juan F. Infante, Maria E. Sarmiento, Frank Camacho, Louise Kim, Viviana Pérez, Graham A. W. Rook, and Jim F. Huggett
- Subjects
Phage display ,Tuberculosis ,Cell Surface Display Techniques ,T-cell receptor ,Immunology ,Biology ,biology.organism_classification ,medicine.disease ,Virology ,Molecular biology ,law.invention ,Mycobacterium tuberculosis ,Cell culture ,law ,medicine ,Recombinant DNA ,Pathogen - Abstract
The development of molecules specific for M. tuberculosis-infected cells has important implications, as these tools may facilitate understanding of the mechanisms regulating host pathogen interactions in vivo. In addition, development of new tools capable to targeting M. tuberculosis-infected cells may have potential applications to diagnosis, treatment, and prevention of tuberculosis (TB). Due to the lack of CD1b polymorphism, M. tuberculosis lipid-CD1b complexes could be considered as universal tuberculosis infection markers. The aim of the present study was to display on the PIII surface protein of m13 phage, a human αβ single-chain T-cell receptor molecule specific for CD1b:2-stearoyl-3-hydroxyphthioceranoyl-2´-sulfate-α-α´-D-trehalose (Ac2SGL) which is a complex presented by human cells infected with M. tuberculosis. The results showed the pIII fusion particle was successfully displayed on the phage surface. The study of the recognition of the recombinant phage in ELISA and immunohistochemistry showed the recognition of CD1b:Ac2SGL complexes and cells in human lung tissue from a tuberculosis patient respectively, suggesting the specific recognition of the lipid-CD1b complex.
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