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Zhang W, Auguste A, Liao X, Walterskirchen C, Bauer K, Lin YH, Yang L, Sayedian F, Fabits M, Bergmann M, Binder C, Corrales L, Vogt AB, Hudson LJ, Barnes MP, Bisht A, Giragossian C, Voynov V, Adam PJ, Hipp S. A Novel B7-H6-Targeted IgG-Like T Cell-Engaging Antibody for the Treatment of Gastrointestinal Tumors. Clin Cancer Res 2022; 28:5190-5201. [PMID: 36166004 PMCID: PMC9713360 DOI: 10.1158/1078-0432.ccr-22-2108] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/22/2022] [Accepted: 09/22/2022] [Indexed: 01/24/2023]
Abstract
PURPOSE Advanced-stage gastrointestinal cancers represent a high unmet need requiring new effective therapies. We investigated the antitumor activity of a novel T cell-engaging antibody (B7-H6/CD3 ITE) targeting B7-H6, a tumor-associated antigen that is expressed in gastrointestinal tumors. EXPERIMENTAL DESIGN Membrane proteomics and IHC analysis identified B7-H6 as a tumor-associated antigen in gastrointestinal tumor tissues with no to very little expression in normal tissues. The antitumor activity and mode of action of B7-H6/CD3 ITE was evaluated in in vitro coculture assays, in humanized mouse tumor models, and in colorectal cancer precision cut tumor slice cultures. RESULTS B7-H6 expression was detected in 98% of colorectal cancer, 77% of gastric cancer, and 63% of pancreatic cancer tissue samples. B7-H6/CD3 ITE-mediated redirection of T cells toward B7-H6-positive tumor cells resulted in B7-H6-dependent lysis of tumor cells, activation and proliferation of T cells, and cytokine secretion in in vitro coculture assays, and infiltration of T cells into tumor tissues associated with tumor regression in in vivo colorectal cancer models. In primary patient-derived colorectal cancer precision-cut tumor slice cultures, treatment with B7-H6/CD3 ITE elicited cytokine secretion by endogenous tumor-infiltrating immune cells. Combination with anti-PD-1 further enhanced the activity of the B7-H6/CD3 ITE. CONCLUSION These data highlight the potential of the B7-H6/CD3 ITE to induce T cell-redirected lysis of tumor cells and recruitment of T cells into noninflamed tumor tissues, leading to antitumor activity in in vitro, in vivo, and human tumor slice cultures, which supports further evaluation in a clinical study.
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Affiliation(s)
- Wei Zhang
- Boehringer Ingelheim Pharmaceuticals, Inc., Cancer Immunology & Immune Modulation, Ridgefield, Connecticut
| | - Aurélie Auguste
- Boehringer Ingelheim Pharma, GmbH & Co KG, Translational Medicine and Clinical Pharmacology, Biberach an der Riß, Germany
| | - Xiaoyun Liao
- Boehringer Ingelheim Pharmaceuticals, Inc., Oncology Translational Science, Ridgefield, Connecticut
| | | | - Kathrin Bauer
- Boehringer Ingelheim RCV, GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Yu-Hsi Lin
- Boehringer Ingelheim Pharmaceuticals, Inc., Cancer Immunology & Immune Modulation, Ridgefield, Connecticut
| | - Ling Yang
- Boehringer Ingelheim Pharmaceuticals, Inc., Cancer Immunology & Immune Modulation, Ridgefield, Connecticut
| | | | - Markus Fabits
- Medical University of Vienna, Division of Visceral Surgery, Department of General Surgery and Comprehensive Cancer Center, Vienna, Austria
| | - Michael Bergmann
- Medical University of Vienna, Division of Visceral Surgery, Department of General Surgery and Comprehensive Cancer Center, Vienna, Austria
| | - Carina Binder
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Leticia Corrales
- Boehringer Ingelheim RCV, GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Anne B. Vogt
- Boehringer Ingelheim RCV, GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | | | | | - Arnima Bisht
- Oxford BioTherapeutics, Inc., San Jose, California
| | - Craig Giragossian
- Boehringer Ingelheim Pharmaceuticals, Inc., Biotherapeutics Discovery, Ridgefield, Connecticut
| | - Vladimir Voynov
- Boehringer Ingelheim Pharmaceuticals, Inc., Biotherapeutics Discovery, Ridgefield, Connecticut
| | - Paul J. Adam
- Boehringer Ingelheim RCV, GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Susanne Hipp
- Boehringer Ingelheim Pharmaceuticals, Inc., Cancer Immunology & Immune Modulation, Ridgefield, Connecticut.,Boehringer Ingelheim Pharmaceuticals, Inc., Translational Medicine and Clinical Pharmacology, Ridgefield, Connecticut.,Corresponding Author: Susanne Hipp, Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, P.O. Box 368, Ridgefield, CT 06877-0368. Phone: 203-798-4567; E-mail:
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Corrales L, Hipp S, Martin K, Sabarth N, Tirapu I, Fuchs K, Thaler B, Walterskirchen C, Bauer K, Fabits M, Bergmann M, Binder C, Chetta PML, Vogt AB, Adam PJ. LY6G6D is a selectively expressed colorectal cancer antigen that can be used for targeting a therapeutic T-cell response by a T-cell engager. Front Immunol 2022; 13:1008764. [PMID: 36159851 PMCID: PMC9493073 DOI: 10.3389/fimmu.2022.1008764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 08/17/2022] [Indexed: 11/13/2022] Open
Abstract
Colorectal cancer (CRC) is one of the most common cancers worldwide and demands more effective treatments. We sought to identify tumor selective CRC antigens and their therapeutic potential for cytotoxic T-cell targeting by transcriptomic and immunohistochemical analysis. LY6G6D was identified as a tumor selectively expressed CRC antigen, mainly in the microsatellite stable (MSS) subtype. A specific anti LY6G6D/CD3 T cell engager (TcE) was generated and demonstrated potent tumor cell killing and T cell activation in vitro. Ex vivo treatment of primary patient-derived CRC tumor slice cultures with the LY6G6D/CD3 TcE led to IFNγ secretion in LY6G6D positive tumor samples. In vivo, LY6G6D/CD3 TcE monotherapy demonstrated tumor regressions in pre-clinical mouse models of engrafted human CRC tumor cells and PBMCs. Lastly, 2D and 3D cocultures of LY6G6D positive and negative cells were used to explore the bystander killing of LY6G6D negative cells after specific activation of T cells by LY6G6D positive cells. LY6G6D/CD3 TcE treatment was shown to lyse target negative cells in the vicinity of target positive cells through a combined effect of IFNγ, TNFα and Fas/FasL. In summary, LY6G6D was identified as a selectively expressed CRC antigen that can be utilized to potently re-direct and activate cytotoxic T-cells to lyse LY6G6D expressing CRC using a TcE. This effect can be spread to target negative neighboring tumor cells, potentially leading to improved therapeutic efficacy.
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Affiliation(s)
- Leticia Corrales
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
- *Correspondence: Leticia Corrales,
| | - Susanne Hipp
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
- Boehringer Ingelheim Pharmaceuticals, Inc., Translational Medicine and Clinical Pharmacology, Ridgefield, CT, United States
| | - Katharina Martin
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Nicolas Sabarth
- Boehringer Ingelheim Regional Center Vienna (RCV) GmbH & Co KG., Biotherapeutics Discovery, Vienna, Austria
| | - Iñigo Tirapu
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Klaus Fuchs
- Boehringer Ingelheim Pharma, GmbH & Co KG, Biotherapeutics Discovery, Biberach, Germany
| | - Barbara Thaler
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Christian Walterskirchen
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Kathrin Bauer
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Markus Fabits
- Division of Visceral Surgery, Department of General Surgery and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Michael Bergmann
- Division of Visceral Surgery, Department of General Surgery and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Carina Binder
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Paolo ML. Chetta
- Boehringer Ingelheim RCV, GmbH & Co KG., Oncology Translational Science, Vienna, Austria
| | - Anne B. Vogt
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
| | - Paul J. Adam
- Boehringer Ingelheim Regional Center Vienna (RCV), GmbH & Co KG., Cancer Immunology & Immune Modulation, Vienna, Austria
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3
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Mostböck S, Wu HH, Fenn T, Riegler B, Strahlhofer S, Huang Y, Hansen G, Kroe-Barrett R, Tirapu I, Vogt AB. Distinct immune stimulatory effects of anti-human VISTA antibodies are determined by Fc-receptor interaction. Front Immunol 2022; 13:862757. [PMID: 35967294 PMCID: PMC9367637 DOI: 10.3389/fimmu.2022.862757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 07/01/2022] [Indexed: 11/13/2022] Open
Abstract
VISTA (PD-1H) is an immune regulatory molecule considered part of the next wave of immuno-oncology targets. VISTA is an immunoglobulin (Ig) superfamily cell surface molecule mainly expressed on myeloid cells, and to some extent on NK cells and T cells. In previous preclinical studies, some VISTA-targeting antibodies provided immune inhibitory signals, while other antibodies triggered immune stimulatory signals. Importantly, for therapeutic antibodies, the isotype backbone can have a strong impact on antibody function. To elucidate the mode of action of immune stimulatory anti-VISTA antibodies, we studied three different anti-human VISTA antibody clones, each on three different IgG isotypes currently used for therapeutic antibodies: unaltered IgG1 (IgG1-WT), IgG1-KO (IgG1-LL234,235AA-variant with reduced Fc-effector function), and IgG4-Pro (IgG4- S228P-variant with stabilized hinge region). Antibody functionality was analysed in mixed leukocyte reaction (MLR) of human peripheral blood mononuclear cells (PBMCs), as a model system for ongoing immune reactions, on unstimulated human PBMCs, as a model system for a resting immune system, and also on acute myeloid leukemia (AML) patient samples to evaluate anti-VISTA antibody effects on primary tumor material. The functions of three anti-human VISTA antibodies were determined by their IgG isotype backbones. An MLR of healthy donor PBMCs was effectively augmented by anti-VISTA-IgG4-Pro and anti-VISTA-IgG1-WT antibodies, as indicated by increased levels of cytokines, T cell activation markers and T cell proliferation. However, in a culture of unstimulated PBMCs of single healthy donors, only anti-VISTA-IgG1-WT antibodies increased the activation marker HLA-DR on resting myeloid cells, and chemokine levels. Interestingly, interactions with different Fc-receptors were required for these effects, namely CD64 for augmentation of MLR, and CD16 for activation of resting myeloid cells. Furthermore, anti-VISTA-IgG1-KO antibodies had nearly no impact in any model system. Similarly, in AML patient samples, anti-VISTA-antibody on IgG4-Pro backbone, but not on IgG1-KO backbone, increased interactions, as a novel readout of activity, between immune cells and CD34+ AML cancer cells. In conclusion, the immune stimulatory effects of antagonistic anti-VISTA antibodies are defined by the antibody isotype and interaction with different Fc-gamma-receptors, highlighting the importance of understanding these interactions when designing immune stimulatory antibody therapeutics for immuno-oncology applications.
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Affiliation(s)
- Sven Mostböck
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
- *Correspondence: Sven Mostböck,
| | - Helen Haixia Wu
- Biotherapeutics Discovery, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, United States
| | - Timothy Fenn
- Biotherapeutics Discovery, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, United States
| | - Bettina Riegler
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Susanne Strahlhofer
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Yining Huang
- Biotherapeutics Discovery, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, United States
| | - Gale Hansen
- Biotherapeutics Discovery, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, United States
| | - Rachel Kroe-Barrett
- Biotherapeutics Discovery, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, United States
| | - Iñigo Tirapu
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Anne B. Vogt
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
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4
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Wurm M, Schaaf O, Reutner K, Ganesan R, Mostböck S, Pelster C, Böttcher J, de Andrade Pereira B, Taubert C, Alt I, Serna G, Auguste A, Stadermann KB, Delic D, Han F, Capdevila J, Nuciforo PG, Kroe-Barrett R, Adam PJ, Vogt AB, Hofmann I. A Novel Antagonistic CD73 Antibody for Inhibition of the Immunosuppressive Adenosine Pathway. Mol Cancer Ther 2021; 20:2250-2261. [PMID: 34482286 PMCID: PMC9398120 DOI: 10.1158/1535-7163.mct-21-0107] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 07/01/2021] [Accepted: 08/30/2021] [Indexed: 01/07/2023]
Abstract
Despite some impressive clinical results with immune checkpoint inhibitors, the majority of patients with cancer do not respond to these agents, in part due to immunosuppressive mechanisms in the tumor microenvironment. High levels of adenosine in tumors can suppress immune cell function, and strategies to target the pathway involved in its production have emerged. CD73 is a key enzyme involved in adenosine production. This led us to identify a novel humanized antagonistic CD73 antibody, mAb19, with distinct binding properties. mAb19 potently inhibits the enzymatic activity of CD73 in vitro, resulting in an inhibition of adenosine formation and enhanced T-cell activation. We then investigated the therapeutic potential of combining CD73 antagonism with other immune modulatory and chemotherapeutic agents. Combination of mAb19 with a PD-1 inhibitor increased T-cell activation in vitro Interestingly, this effect could be further enhanced with an agonist of the adenosine receptor ADORA3. Adenosine levels were found to be elevated upon doxorubicin treatment in vivo, which could be blocked by CD73 inhibition. Combining CD73 antagonism with doxorubicin resulted in superior responses in vivo Furthermore, a retrospective analysis of rectal cancer patient samples demonstrated an upregulation of the adenosine pathway upon chemoradiation, providing further rationale for combining CD73 inhibition with chemotherapeutic agents.This study demonstrates the ability of a novel CD73 antibody to enhance T-cell function through the potent suppression of adenosine levels. In addition, the data highlight combination opportunities with standard of care therapies as well as with an ADORA3 receptor agonist to treat patients with solid tumors.
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Affiliation(s)
- Melanie Wurm
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Pharmacology and Disease Positioning, Vienna, Austria
| | - Otmar Schaaf
- Boehringer Ingelheim RCV, GmbH & Co KG, Drug Discovery Sciences, Vienna, Austria
| | - Katharina Reutner
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Immunology and Immune Modulation, Vienna, Austria
| | - Rajkumar Ganesan
- Boehringer Ingelheim Pharmaceuticals, Inc., Biotherapeutics Discovery, Ridgefield, Conneticut
| | - Sven Mostböck
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Immunology and Immune Modulation, Vienna, Austria
| | - Christina Pelster
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Immunology and Immune Modulation, Vienna, Austria
| | - Jark Böttcher
- Boehringer Ingelheim RCV, GmbH & Co KG, Drug Discovery Sciences, Vienna, Austria
| | | | | | | | - Garazi Serna
- Vall d´Hebron University Hospital, Vall d´Hebron Institute of Oncology, CIBERONC, Universitat Autonoma de Barcelona, Barcelona, Spain
| | - Aurelie Auguste
- Boehringer Ingelheim Pharma GmbH & Co KG, Translational Medicine and Clinical Pharmacology, Biberach, Germany
| | - Kai B Stadermann
- Boehringer Ingelheim Pharma GmbH & Co KG, Translational Medicine and Clinical Pharmacology, Biberach, Germany
| | - Denis Delic
- Boehringer Ingelheim Pharma GmbH & Co KG, Translational Medicine and Clinical Pharmacology, Biberach, Germany
| | - Fei Han
- Boehringer Ingelheim Pharmaceuticals, Inc., Biotherapeutics Discovery, Ridgefield, Conneticut
| | - Jaume Capdevila
- Vall d´Hebron University Hospital, Vall d´Hebron Institute of Oncology, CIBERONC, Universitat Autonoma de Barcelona, Barcelona, Spain
| | - Paolo G Nuciforo
- Vall d´Hebron University Hospital, Vall d´Hebron Institute of Oncology, CIBERONC, Universitat Autonoma de Barcelona, Barcelona, Spain
| | - Rachel Kroe-Barrett
- Boehringer Ingelheim Pharmaceuticals, Inc., Biotherapeutics Discovery, Ridgefield, Conneticut
| | - Paul J Adam
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Immunology and Immune Modulation, Vienna, Austria
| | - Anne B Vogt
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Immunology and Immune Modulation, Vienna, Austria
| | - Irmgard Hofmann
- Boehringer Ingelheim RCV, GmbH & Co KG, Cancer Immunology and Immune Modulation, Vienna, Austria.
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5
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Zhang Q, He Y, Luo N, Patel SJ, Han Y, Gao R, Modak M, Carotta S, Haslinger C, Kind D, Peet GW, Zhong G, Lu S, Zhu W, Mao Y, Xiao M, Bergmann M, Hu X, Kerkar SP, Vogt AB, Pflanz S, Liu K, Peng J, Ren X, Zhang Z. Landscape and Dynamics of Single Immune Cells in Hepatocellular Carcinoma. Cell 2019; 179:829-845.e20. [PMID: 31675496 DOI: 10.1016/j.cell.2019.10.003] [Citation(s) in RCA: 753] [Impact Index Per Article: 150.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/14/2019] [Accepted: 10/03/2019] [Indexed: 02/08/2023]
Abstract
The immune microenvironment of hepatocellular carcinoma (HCC) is poorly characterized. Combining two single-cell RNA sequencing technologies, we produced transcriptomes of CD45+ immune cells for HCC patients from five immune-relevant sites: tumor, adjacent liver, hepatic lymph node (LN), blood, and ascites. A cluster of LAMP3+ dendritic cells (DCs) appeared to be the mature form of conventional DCs and possessed the potential to migrate from tumors to LNs. LAMP3+ DCs also expressed diverse immune-relevant ligands and exhibited potential to regulate multiple subtypes of lymphocytes. Of the macrophages in tumors that exhibited distinct transcriptional states, tumor-associated macrophages (TAMs) were associated with poor prognosis, and we established the inflammatory role of SLC40A1 and GPNMB in these cells. Further, myeloid and lymphoid cells in ascites were predominantly linked to tumor and blood origins, respectively. The dynamic properties of diverse CD45+ cell types revealed by this study add new dimensions to the immune landscape of HCC.
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Affiliation(s)
- Qiming Zhang
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China
| | - Yao He
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Nan Luo
- Department of Surgery, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China; Ninth School of Clinical Medicine, Peking University, Beijing 100038, China
| | - Shashank J Patel
- Department of Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877, USA
| | - Yanjie Han
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China
| | - Ranran Gao
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China
| | - Madhura Modak
- Department of Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharma, Birkendorfer Str. 65, 88400 Biberach, Germany
| | - Sebastian Carotta
- Department of Cancer Cell Signaling, Boehringer Ingelheim RCV GmBH & Co KG., Dr. Boehringer Gasse 5-11, 1120 Vienna, Austria
| | - Christian Haslinger
- Department of Computational Biology and Genomics, Boehringer Ingelheim Pharma, Birkendorfer Str. 65, 88400 Biberach, Germany
| | - David Kind
- Department of Computational Biology and Genomics, Boehringer Ingelheim Pharma, Birkendorfer Str. 65, 88400 Biberach, Germany
| | - Gregory W Peet
- Department of Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877, USA
| | - Guojie Zhong
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China
| | - Shuangjia Lu
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China
| | - Weihua Zhu
- Department of Hepatobiliary Surgery, Peking University People's Hospital, Beijing 100044, China
| | - Yilei Mao
- Department of Liver Surgery, Peking Union Medical College Hospital, Beijing 100730, China
| | - Mengmeng Xiao
- Department of Retroperitoneal Tumor Surgery, Peking University International Hospital, Beijing 102206, China
| | - Michael Bergmann
- Department of Surgery and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Xueda Hu
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China
| | - Sid P Kerkar
- Department of Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877, USA
| | - Anne B Vogt
- Department of Human Cancer Immunology, Boehringer Ingelheim RCV GmBH & Co KG., Dr. Boehringer Gasse 5-11, 1120 Vienna, Austria
| | - Stefan Pflanz
- Department of Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharma, Birkendorfer Str. 65, 88400 Biberach, Germany
| | - Kang Liu
- Department of Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877, USA.
| | - Jirun Peng
- Department of Surgery, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China; Ninth School of Clinical Medicine, Peking University, Beijing 100038, China.
| | - Xianwen Ren
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China.
| | - Zemin Zhang
- BIOPIC, Beijing Advanced Innovation Center for Genomics, School of Life Sciences, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.
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Karle AC, Oostingh GJ, Mutschlechner S, Ferreira F, Lackner P, Bohle B, Fischer GF, Vogt AB, Duschl A. Nitration of the pollen allergen bet v 1.0101 enhances the presentation of bet v 1-derived peptides by HLA-DR on human dendritic cells. PLoS One 2012; 7:e31483. [PMID: 22348091 PMCID: PMC3279363 DOI: 10.1371/journal.pone.0031483] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 01/09/2012] [Indexed: 11/19/2022] Open
Abstract
Nitration of pollen derived allergens can occur by NO2 and ozone in polluted air and it has already been shown that nitrated major birch (Betula verrucosa) pollen allergen Bet v 1.0101 (Bet v 1) exhibits an increased potency to trigger an immune response. However, the mechanisms by which nitration might contribute to the induction of allergy are still unknown. In this study, we assessed the effect of chemically induced nitration of Bet v 1 on the generation of HLA-DR associated peptides. Human dendritic cells were loaded with unmodified Bet v 1 or nitrated Bet v 1, and the naturally processed HLA-DR associated peptides were subsequently identified by liquid chromatography-mass spectrometry. Nitration of Bet v 1 resulted in enhanced presentation of allergen-derived HLA-DR-associated peptides. Both the copy number of Bet v 1 derived peptides as well as the number of nested clusters was increased. Our study shows that nitration of Bet v 1 alters antigen processing and presentation via HLA-DR, by enhancing both the quality and the quantity of the Bet v 1-specific peptide repertoire. These findings indicate that air pollution can contribute to allergic diseases and might also shed light on the analogous events concerning the nitration of self-proteins.
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Affiliation(s)
- Anette C. Karle
- Immunosafety, Non-Clinical Drug Safety, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Gertie J. Oostingh
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Sonja Mutschlechner
- Christian Doppler Laboratory for Immunomodulation, Department of Pathophysiology, Center of Physiology, Pathophysiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Fatima Ferreira
- Christian Doppler Laboratory for Allergy Diagnosis and Therapy, Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Peter Lackner
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Barbara Bohle
- Christian Doppler Laboratory for Immunomodulation, Department of Pathophysiology, Center of Physiology, Pathophysiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Gottfried F. Fischer
- Clinical Department for Blood Group Serology, University Clinic for Blood Group Serology and Transfusion Medicine, Vienna, Austria
| | - Anne B. Vogt
- Immunosafety, Non-Clinical Drug Safety, F. Hoffmann-La Roche Ltd, Basel, Switzerland
- * E-mail:
| | - Albert Duschl
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
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7
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Mutschlechner S, Egger M, Briza P, Wallner M, Lackner P, Karle A, Vogt AB, Fischer GF, Bohle B, Ferreira F. Naturally processed T cell-activating peptides of the major birch pollen allergen. J Allergy Clin Immunol 2010; 125:711-8, 718.e1-718.e2. [PMID: 20132976 DOI: 10.1016/j.jaci.2009.10.052] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 10/06/2009] [Accepted: 10/29/2009] [Indexed: 11/29/2022]
Abstract
BACKGROUND Although antigen processing and presentation of allergens to CD4(+)T lymphocytes are key events in the pathophysiology of allergic disorders, they still remain poorly understood. OBJECTIVE To investigate allergen processing and presentation by dendritic cells using the major birch pollen allergen Bet v 1 as a model. METHODS Endolysosomal extracts of dendritic cells derived from patients with birch pollen allergy were used to digest Bet v 1. Dendritic cells were pulsed with Bet v 1, and peptides were eluted from MHC class II molecules. Peptides obtained by either approach were sequenced by tandem mass spectrometry. Bet v 1-specific T-cell cultures were stimulated with HLA-DR-eluted Bet v 1-derived peptides. Bet v 1-specific T-cell lines were generated from each patient and analyzed for epitope recognition. RESULTS A high proportion of Bet v 1 remained intact for a long period of endolysosomal degradation. The peptides that appeared early in the degradation process contained frequently recognized T-cell epitopes. Bet v 1-derived peptides eluted from MHC class II molecules corresponded to those generated by endolysosomal degradation, matched known T-cell epitopes, and showed T cell-activating capacity. The Bet v 1-specific T-cell line of each individual harbored T cells reactive with peptides located within the MHC class II-eluted Bet v 1-derived sequences demonstrating their occurrence in vivo. CONCLUSION We report for the first time how epitopes of allergens are generated and selected for presentation to T lymphocytes. The limited susceptibility of Bet v 1 to endolysosomal processing might contribute to its high allergenic potential.
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Affiliation(s)
- Sonja Mutschlechner
- Christian Doppler Laboratory for Allergy Diagnosis and Therapy, Department of Molecular Biology, University of Salzburg, Salzburg, Austria
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8
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Röhn TA, Reitz A, Paschen A, Nguyen XD, Schadendorf D, Vogt AB, Kropshofer H. A Novel Strategy for the Discovery of MHC Class II–Restricted Tumor Antigens: Identification of a Melanotransferrin Helper T-Cell Epitope. Cancer Res 2005; 65:10068-78. [PMID: 16267033 DOI: 10.1158/0008-5472.can-05-1973] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
CD4+ helper T cells play a critical role in orchestrating host immune responses, including antitumor immunity. The limited availability of MHC class II-associated tumor antigens is still viewed as a major obstacle in the use of CD4+ T cells in cancer vaccines. Here, we describe a novel approach for the identification of MHC class II tumor-associated antigens (TAAs). By combining two-dimensional liquid chromatography and nanoelectrospray ionization tandem mass spectrometry, we developed a highly sensitive method for the detection of human leukocyte antigen (HLA)-DR-associated peptides of dendritic cells upon exposure to necrotic tumor cells. This approach led to the identification of a novel MHC class II-restricted TAA epitope derived from melanotransferrin. The epitope stimulated T cells derived from melanoma patients and healthy individuals and displayed promiscuity in HLA-DR restriction. Moreover, the same peptide was also presented by MHC class II-positive melanoma cells. This strategy may contribute to increase the number of tumor epitopes presented by MHC class II molecules and may support the development of more efficacious vaccines against cancer.
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Affiliation(s)
- Till A Röhn
- Pharmaceutical Research and Roche Center for Medical Genomics, F. Hoffmann La Roche Ltd., Basel, Switzerland
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9
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Röhn TA, Schadendorf D, Sun Y, Nguyen XD, Roeder D, Langen H, Vogt AB, Kropshofer H. Melanoma cell necrosis facilitates transfer of specific sets of antigens onto MHC class II molecules of dendritic cells. Eur J Immunol 2005; 35:2826-39. [PMID: 16163671 DOI: 10.1002/eji.200526299] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Vaccine strategies that target dendritic cells (DC) in order to elicit immunity against tumors are the subject of intense research. For the induction and maintenance of anti-tumor immunity, CD4+ helper T cells are often required, which need to see appropriate MHC class II-peptide complexes on DC. So far, it remained widely unclear what type of tumor cells can feed the MHC class II processing pathway of DC with what type of antigens. Here, we report that peptide loading onto MHC class II molecules of myeloid DC is facilitated by melanoma cells undergoing necrotic rather than apoptotic cell death. Importantly, the set of MHC class II-associated peptides induced by necrotic tumor cells differed from those found upon engagement of apoptotic tumor cells. This may be due to the fact that only necrotic cells liberated heat shock proteins, which bind tumor-derived peptides and thereby may promote processing by DC. The potential of DC to activate T cells was kinetically controlled through their antigen receptivity: CD4+ T cells were easily stimulated upon encountering antigen early in DC maturation, whereas antigen capture at later maturation stages favored activation of CD8+ T cells. These findings may aid in designing future vaccination strategies and in identifying novel tumor-specific helper T cell antigens.
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Affiliation(s)
- Till A Röhn
- Basel Institute for Immunology, Basel, Switzerland
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10
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Röhn TA, Boes M, Wolters D, Spindeldreher S, Müller B, Langen H, Ploegh H, Vogt AB, Kropshofer H. Upregulation of the CLIP self peptide on mature dendritic cells antagonizes T helper type 1 polarization. Nat Immunol 2004; 5:909-18. [PMID: 15322540 DOI: 10.1038/ni1108] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Accepted: 07/28/2004] [Indexed: 11/10/2022]
Abstract
Dendritic cells (DCs) initiate and regulate immunity against foreign and self antigens. Here we identified more than 200 individual major histocompatibility complex class II-associated peptides on human DCs and found that mature DCs selectively upregulated the self peptide CLIP. CLIP cosegregated together with foreign antigenic peptides in tetraspan microdomains on the surface and localized to DC-T cell synapses. The increased representation of CLIP-major histocompatibility complex class II complexes favored polarization of autologous naive T cells toward the nonpolarized and T helper type 2 (T(H)2) phenotype. There was also a considerably higher T(H)2/T(H)1 ratio in H2-DM-deficient mice, which have a CLIP(hi) phenotype, in contrast to wild-type, CLIP(lo) mice. Thus, the self peptide CLIP on DCs qualifies as an endogenous regulator in priming of T helper cells by antagonizing the polarization toward the T(H)1 phenotype.
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Affiliation(s)
- Till A Röhn
- Basel Institute for Immunology, Basel, Switzerland
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11
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Chalouni C, Banchereau J, Vogt AB, Pascual V, Davoust J. Human germinal center B cells differ from naive and memory B cells by their aggregated MHC class II-rich compartments lacking HLA-DO. Int Immunol 2003; 15:457-66. [PMID: 12663675 DOI: 10.1093/intimm/dxg037] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
To generate memory B cells bearing high-affinity antibodies, naive B cells first encounter antigen in the T cell-rich areas of secondary lymphoid organs. There, they are activated by antigen-specific T cells and become germinal center (GC) founder B cells. GC founders enter the GC to become centroblasts that proliferate and mutate their BCR. Centroblasts differentiate into centrocytes that undergo selection, which requires both the recognition/capture of antigen on follicular dendritic cells and the presentation of processed antigen to GC T cells. Because at each stage of differentiation B cells act as antigen-presenting cells, we analyzed their content of HLA-DR(+)-rich compartments (MIIC), as well as their expression of HLA-DM, which catalyzes peptide loading of class II molecules, and HLA-DO, which interacts with HLA-DM and focuses MHC class II peptide loading on antigens internalized by the BCR. Naive and memory B cells concentrate HLA-DR, -DM and -DO into compartments dispersed under the cell surface, which are identified by their expression of lysosome-associated membrane protein (Lamp)-1 as late endosomes/lysosomes. GC founders and GC B cells express larger Lamp-1(+)DR(+) compartments that are concentrated in the juxta-nuclear region. These compartments express lower levels of HLA-DM and virtually no HLA-DO. Upon induction of a GC founder phenotype through the prolonged (days) co-ligation of BCR and CD40, the naive B cell's peripheral DR(+)DM(+)Lamp-1(+) compartments aggregate in a polar fashion close to the nucleus. Furthermore, HLA-DO expression virtually disappears, whereas low levels of HLA-DM remain co-localized with HLA-DR. Anti-kappa/lambda antibodies, used as surrogate antigens, are promptly (minutes) endocytosed in naive, memory and GC B cells. Then, naive and memory B cells target the surrogate antigen to their peripheral HLA-DO(+) MIIC, while GC B cells target it to their HLA-DO(-) MIIC aggregates. Taken together, our results show that human GC B cells differ from naive and memory B cells by their aggregated MIIC that lack HLA-DO.
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Affiliation(s)
- Cécile Chalouni
- Baylor Institute for Immunology Research, Dallas, TX 75204, USA
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12
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Koonce CH, Wutz G, Robertson EJ, Vogt AB, Kropshofer H, Bikoff EK. DM loss in k haplotype mice reveals isotype-specific chaperone requirements. J Immunol 2003; 170:3751-61. [PMID: 12646641 DOI: 10.4049/jimmunol.170.7.3751] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
DM actions as a class II chaperone promote capture of diverse peptides inside the endocytic compartment(s). DM mutant cells studied to date express class II bound by class II-associated invariant chain-derived peptide (CLIP), a short proteolytic fragment of the invariant chain, and exhibit defective peptide-loading abilities. To evaluate DM functional contributions in k haplotype mice, we engineered a novel mutation at the DMa locus via embryonic stem cell technology. The present experiments demonstrate short-lived A(k)/CLIP complexes, decreased A(k) surface expression, and enhanced A(k) peptide binding activities. Thus, we conclude that DM loss in k haplotype mice creates a substantial pool of empty or loosely occupied A(k) conformers. On the other hand, the mutation hardly affects E(k) activities. The appearance of mature compact E(k) dimers, near normal surface expression, and efficient Ag presentation capabilities strengthen the evidence for isotype-specific DM requirements. In contrast to DM mutants described previously, partial occupancy by wild-type ligands is sufficient to eliminate antiself reactivity. Mass spectrometry profiles reveal A(k)/CLIP and a heterogeneous collection of relatively short peptides bound to E(k) molecules. These experiments demonstrate that DM has distinct roles depending on its specific class II partners.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigen Presentation/genetics
- Antigens, Differentiation, B-Lymphocyte/biosynthesis
- Antigens, Differentiation, B-Lymphocyte/genetics
- Antigens, Differentiation, B-Lymphocyte/metabolism
- Crosses, Genetic
- Female
- Gene Deletion
- H-2 Antigens/genetics
- Haplotypes
- Histocompatibility Antigens Class II/biosynthesis
- Histocompatibility Antigens Class II/classification
- Histocompatibility Antigens Class II/genetics
- Histocompatibility Antigens Class II/metabolism
- Histocompatibility Antigens Class II/physiology
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Knockout
- Molecular Chaperones/classification
- Molecular Chaperones/physiology
- Molecular Sequence Data
- Muramidase/immunology
- Muramidase/metabolism
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- RNA Editing/immunology
- Self Tolerance/genetics
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Affiliation(s)
- Chad H Koonce
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
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13
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Vogt AB, Spindeldreher S, Kropshofer H. Clustering of MHC-peptide complexes prior to their engagement in the immunological synapse: lipid raft and tetraspan microdomains. Immunol Rev 2002; 189:136-51. [PMID: 12445271 DOI: 10.1034/j.1600-065x.2002.18912.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Protein reorganization at the interface of a T cell and an antigen-presenting cell (APC) plays an important role in T cell activation. Imaging techniques reveal that reorganization of particular receptor-ligand pairs gives rise to an intercellular junction, termed the immunological synapse. In this synapse antigenic peptides associated with major histocompatibility complex (MHC) molecules form multimolecular arrays on the APC side, engaging an equivalent number of clustered T cell receptors (TCRs) on the T cell. The accumulation of MHC molecules carrying cognate peptide in the APC-T cell interface was thought to depend on the specificity and presence of TCRs. Recent evidence, however, suggests that the APC is equipped to preorganize MHC-peptide complexes in the absence of T cells. To this end, MHC molecules become incorporated into two types of membrane microdomains: (i) cholesterol- and glycosphingolipid-enriched domains, denoted lipid rafts, that preconcentrate MHC class II molecules; and (ii) microdomains made up of tetraspan proteins, such as CD9, CD63, CD81 or CD82, that mediate enrichment of MHC class II molecules loaded with a select set of peptides. It follows that the integrity, composition and dynamics of these microdomains are candidate determinants favoring activation or silencing of T cells.
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Affiliation(s)
- Anne B Vogt
- Roche Center for Medical Genomics, F. Hoffmann-La Roche, Ltd, Basel, Switzerland
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14
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Kropshofer H, Spindeldreher S, Röhn TA, Platania N, Grygar C, Daniel N, Wölpl A, Langen H, Horejsi V, Vogt AB. Tetraspan microdomains distinct from lipid rafts enrich select peptide-MHC class II complexes. Nat Immunol 2002; 3:61-8. [PMID: 11743588 DOI: 10.1038/ni750] [Citation(s) in RCA: 181] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Complexes of peptide and major histocompatibility complex (MHC) class II are expressed on the surface of antigen-presenting cells but their molecular organization is unknown. Here we show that subsets of MHC class II molecules localize to membrane microdomains together with tetraspan proteins, the peptide editor HLA-DM and the costimulator CD86. Tetraspan microdomains differ from other membrane areas such as lipid rafts, as they enrich MHC class II molecules carrying a selected set of peptide antigens. Antigen-presenting cells deficient in tetraspan microdomains have a reduced capacity to activate CD4+ T cells. Thus, the organization of uniformly loaded peptide-MHC class II complexes in tetraspan domains may be a very early event that determines both the composition of the immunological synapse and the quality of the subsequent T helper cell response.
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MESH Headings
- Amino Acid Sequence
- Antibodies, Monoclonal/immunology
- Antigen Presentation
- Antigens/immunology
- Antigens, CD/immunology
- Antigens, Differentiation, B-Lymphocyte/immunology
- B-Lymphocytes/drug effects
- B-Lymphocytes/immunology
- B7-2 Antigen
- CD4-Positive T-Lymphocytes/immunology
- Cell Communication
- Cell Compartmentation
- Cell Line, Transformed
- Cyclodextrins/pharmacology
- Endosomes/metabolism
- HLA-D Antigens/immunology
- HLA-DP Antigens/immunology
- HLA-DR Antigens/immunology
- Histocompatibility Antigens Class II/immunology
- Humans
- Hybridomas/immunology
- Lipopolysaccharides/pharmacology
- Lymphocyte Activation
- Lysosomes/metabolism
- Macromolecular Substances
- Membrane Glycoproteins/immunology
- Membrane Microdomains/drug effects
- Membrane Microdomains/immunology
- Membrane Proteins/analysis
- Microscopy, Confocal
- Molecular Sequence Data
- Peptide Fragments/immunology
- Receptors, Antigen, T-Cell/immunology
- Saponins/pharmacology
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- beta-Cyclodextrins
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Affiliation(s)
- H Kropshofer
- Basel Institute for Immunology, 4005 Basel, Switzerland.
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15
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Kasai M, Kropshofer H, Vogt AB, Kominami E, Mizuochi T. CLIP-derived self peptides bound to MHC class II molecules of medullary thymic epithelial cells differ from those of cortical thymic epithelial cells in their diversity, length, and C-terminal processing. Eur J Immunol 2000; 30:3542-51. [PMID: 11169395 DOI: 10.1002/1521-4141(200012)30:12<3542::aid-immu3542>3.0.co;2-n] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Medullary thymic epithelial cells (mTEC) are able to present soluble antigens to CD4+ helper T cell lines, whereas cortical thymic epithelial cells (cTEC) are not (Mizuochi, T., et al., J. Exp. Med. 1992. 175: 1601-1605). In addition, class II heterodimers from mTEC migrated with apparently less relative molecular mass in SDS-PAGE than those from cTEC (Kasai, M., et al., Eur. J. Immunol. 1998. 28:1867-1876). To investigate the cause of the distinct migration profiles of class II heterodimers in both TEC types, class II heterodimer-associated peptides were analyzed by matrix-assisted laser desorption ionization mass spectrometry. Self peptides from cTEC were shown to vary moderately in length and to be highly diverse, including low amounts of CLIP (class II-associated invariant chain peptide) variants. On the other hand, self peptides from two mTEC consisted predominantly of two CLIP variants with exceptional C-terminal extensions. C-terminally overhanging residues of CLIP in mTEC may be responsible for the distinct migration of class II heterodimers in SDS-PAGE. Differences in migration of class II heterodimers on SDS gels was also observed in H2-DM+ vesicles isolated from both TEC. The possible contribution of self peptides bound to class II heterodimers in TEC to positive or negative selection of T cells in the thymus is discussed.
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Affiliation(s)
- M Kasai
- Department of Bacterial and Blood Products, National Institute of Infectious Diseases, Tokyo, Japan.
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16
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Arndt SO, Vogt AB, Markovic-Plese S, Martin R, Moldenhauer G, Wölpl A, Sun Y, Schadendorf D, Hämmerling GJ, Kropshofer H. Functional HLA-DM on the surface of B cells and immature dendritic cells. EMBO J 2000; 19:1241-51. [PMID: 10716924 PMCID: PMC305665 DOI: 10.1093/emboj/19.6.1241] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HLA-DM (DM) plays a critical role in antigen presentation through major histocompatibility complex (MHC) class II molecules. DM functions as a molecular chaperone by keeping class II molecules competent for antigenic peptide loading and serves as an editor by favoring presentation of high-stability peptides. Until now, DM has been thought to exert these activities only in late endosomal/lysosomal compartments of antigen-presenting cells. Here we show that a subset of DM resides at the cell surface of B cells and immature dendritic cells. Surface DM engages in complexes with putatively empty class II molecules and controls presentation of those antigens that rely on loading on the cell surface or in early endosomal recycling compartments. For example, epitopes derived from myelin basic protein that are implicated in the autoimmune disease multiple sclerosis are down-modulated by DM, but are presented in the absence of DM. Thus, this novel concept of functional DM on the surface may be relevant to both protective immune responses and autoimmunity.
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Affiliation(s)
- S O Arndt
- Department of Molecular Immunology, German Cancer Research Center, D-69120 Heidelberg, Germany
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17
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Abstract
Peptide binding to classical major histocompatibility complex (MHC) class II molecules is known to be determined by the properties of the class II peptide binding groove but recently it turned out to be co-controlled by the activity of the non-classical MHC molecules HLA-DM and HLA-DO: HLA-DM functions as a mediator of peptide exchange. In addition, HLA-DM is a chaperone for MHC class II molecules in endosomal and lysosomal loading compartments because it stabilizes the empty MHC class II peptide binding groove and keeps it receptive for peptide loading until appropriate peptide ligands are captured. Since HLA-DM favors the generation of high-stability peptide-MHC class II complexes by releasing low-stability peptide ligands, DM activity affects the peptide repertoire presented on the cell surface of antigen-presenting cells. HLA-DO is expressed mainly in B cells and binds tightly to HLA-DM thereby modulating its activity. Together, HLA-DM and HLA-DO are critical factors in shaping the MHC class II-associated self or foreign peptide repertoire of antigen presenting cells and, hence, govern initiation or prevention of an immune response.
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Affiliation(s)
- H Kropshofer
- Department of Molecular Immunology, German Cancer Research Center, Heidelberg, Germany
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18
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Abstract
For many years the crucial components involved in MHC class II mediated antigen presentation have been thought to be known: polymorphic MHC class II molecules, the monomorphic invariant chain (li) and a set of conventional proteases that cleave antigenic proteins thereby generating ligands able to associate with MHC class II molecules. However, in 1994 it was found that without an additional molecule, HLA-DM (DM), efficient presentation of protein antigens cannot be achieved. Biochemical studies showed that DM acts as a molecular chaperone protecting empty MHC class II molecules from functional inactivation. In addition, it serves as a peptide editor: DM catalyzes not only the release of the invariant chain remnant CLIP, but of all sorts of low-stability peptides, and simultaneously favors binding of high-stability peptides. Through this quality control of peptide loading, DM enables APCs to optimize MHC restriction and to display their antigenic peptide cargo on the surface for prolonged periods of time to be scrutinized by T cells.
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Affiliation(s)
- A B Vogt
- German Cancer Research Center, Department of Molecular Immunology, Im Neuenheimer Feld 280, Heidelberg, D-69120, Germany
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19
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Affiliation(s)
- G J Hämmerling
- Division of Molecular Immunology, German Cancer Research Center, Heidelberg, Germany.
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20
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Abstract
Molecular chaperones are involved in a variety of cellular processes, including stabilization of newly synthesized polypeptide chains, assembly of oligomers, transport of proteins and organelle biogenesis. They are known to exert their activity in the cytosol, endoplasmic reticulum, mitochondria and chloroplasts. HLA-DM is the first example of a molecular chaperone that operates in lysosomes: it plays a crucial role in endosomal and lysosomal compartments during loading of major histocompatibility complex (MHC) class II molecules, specialized peptide receptors that are expressed by antigen-presenting cells of the immune system.
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Affiliation(s)
- A B Vogt
- Dept of Molecular Immunology, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
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21
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Raddrizzani L, Bono E, Vogt AB, Kropshofer H, Gallazzi F, Sturniolo T, Hämmerling GJ, Sinigaglia F, Hammer J. Identification of destabilizing residues in HLA class II-selected bacteriophage display libraries edited by HLA-DM. Eur J Immunol 1999; 29:660-8. [PMID: 10064083 DOI: 10.1002/(sici)1521-4141(199902)29:02<660::aid-immu660>3.0.co;2-i] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
HLA-DM (DM) functions as a peptide editor by catalyzing the release of class II-associated invariant chain peptides (CLIP) and other unstable peptides, thus supporting the formation of stable class II-peptide complexes for presentation. To investigate the general features that determine the DM susceptibility of HLA-DR1/peptide complexes, we generated a large DM-sensitive peptide repertoire from an M13 bacteriophage display library using a novel double selection protocol: we selected bacteriophage capable of binding to DR1 molecules and, subsequently, we enriched DR1-bound bacteriophage susceptible to elution by purified DM molecules. Sequence and mutational analyses of the DR1/DM double-selected peptides revealed that the amino acids Gly and Pro play a destabilizing role in the dissociation kinetics of DR1 ligands. This observation was confirmed also in natural peptide sequences such as CLIP 89-101, HA 307-319 and bovine collagen II (CII) 261-273. Our results demonstrate that DM susceptibility does not only depend on the number and nature of anchor residues, or the peptide length. Instead, less obvious sequence characteristics play a major role in the DM editing process and ultimately in the composition of peptide repertoires presented to T cells.
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22
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Takahashi K, Kropshofer H, Vogt AB, Gleichmann E, Griem P. Drug-induced inhibition of insulin recognition by T-cells: the antirheumatic drug aurothiomalate inhibits MHC binding of insulin peptide. Mol Immunol 1998; 35:1081-7. [PMID: 10395197 DOI: 10.1016/s0161-5890(98)00106-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Previous work has shown that the Au(I) moiety of the antirheumatic drug disodium aurothiomalate (Au(I)TM) can selectively inhibit the response of murine CD4+ T-cell hybridomas to antigenic peptides containing two or more cysteine (Cys) residues. Here, we investigated the mechanism that underlies the inhibitory effect of Au(I)TM on T-cell recognition of bovine insulin (BI). We found that low concentrations of Au(I)TM (10 microM) inhibited the BI-induced proliferation of bulk T-cells from BI-immunized BALB/c mice as well as the IL-2 release of Ab- and Ad-restricted T-cell hybridoma clones. Au(I)TM was found to inhibit binding of the immunodominant BI peptide A1-14 to isolated MHC class II molecules. We suggest that Au(I) forms stable chelate complexes with thiol groups of two Cys residues in the BI A1-14 peptide. Conceivably, formation of these metal-peptide complexes keeps the peptide in a sterical conformation that cannot undergo binding to MHC class II molecules, resulting in an inhibition of T-cell activation due to insufficient peptide presentation.
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Affiliation(s)
- K Takahashi
- Division of Immunology, Medical Institute of Environmental Hygiene, Düsseldorf, Germany
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23
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Siklodi B, Vogt AB, Kropshofer H, Falcioni F, Molina M, Bolin DR, Campbell R, Hämmerling GJ, Nagy ZA. Binding affinity independent contribution of peptide length to the stability of peptide-HLA-DR complexes in live antigen presenting cells. Hum Immunol 1998; 59:463-71. [PMID: 9712349 DOI: 10.1016/s0198-8859(98)00038-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The effect of peptide length on the stability of peptide-HLR-DR1 (DR1) complexes was analyzed using two peptide series of increasing length, each containing a 7mer core with five DR1-binding anchors, extended stepwise with Ala residues at the N- and C-terminus, respectively. The Ala extensions, although did not affect binding affinity, significantly increased the half lives of peptide-DR1 complexes (from 1.5 h up to 10 h) in live antigen presenting cells (APC). Flanking residues from position -2 to 0 and 8 to 11 were involved in the affinity-independent increase of complex stability. The shortest (8mer and 9mer) peptides, with in vivo half lives of <2.5 h, were unable to form stable complexes with DR1 in presence of HLA-DM (DM) molecules, and were poor competitors of antigen presentation. Longer peptides were resistant to DM-mediated unloading, and were efficient competitors of antigen presentation. Thus, DM appears to limit short peptides in establishing biologically relevant DR occupancy, despite their high binding affinity. In APC, stable complexes can form only with high affinity peptides of >9 residues, and the longevity of complexes seems to depend on full of occupation of the binding site.
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Affiliation(s)
- B Siklodi
- Department of Immunology, Hoffmann-La Roche Inc., Nutley, New Jersey 07110-1199, USA
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24
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Kropshofer H, Vogt AB, Thery C, Armandola EA, Li BC, Moldenhauer G, Amigorena S, Hämmerling GJ. A role for HLA-DO as a co-chaperone of HLA-DM in peptide loading of MHC class II molecules. EMBO J 1998; 17:2971-81. [PMID: 9606180 PMCID: PMC1170637 DOI: 10.1093/emboj/17.11.2971] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In B cells, the non-classical human leukocyte antigens HLA-DO (DO) and HLA-DM (DM) are residents of lysosome-like organelles where they form tight complexes. DM catalyzes the removal of invariant chain-derived CLIP peptides from classical major histocompatibility complex (MHC) class II molecules, chaperones them until peptides are available for loading, and functions as a peptide editor. Here we show that DO preferentially promotes loading of MHC class II molecules that are dependent on the chaperone activity of DM, and influences editing in a positive way for some peptides and negatively for others. In acidic compartments, DO is engaged in DR-DM-DO complexes whose physiological relevance is indicated by the observation that at lysosomal pH DM-DO stabilizes empty class II molecules more efficiently than DM alone. Moreover, expression of DO in a melanoma cell line favors loading of high-stability peptides. Thus, DO appears to act as a co-chaperone of DM, thereby controlling the quality of antigenic peptides to be presented on the cell surface.
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Affiliation(s)
- H Kropshofer
- German Cancer Research Center, Department of Molecular Immunology, Heidelberg, Germany
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25
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Faigle W, Raposo G, Tenza D, Pinet V, Vogt AB, Kropshofer H, Fischer A, de Saint-Basile G, Amigorena S. Deficient peptide loading and MHC class II endosomal sorting in a human genetic immunodeficiency disease: the Chediak-Higashi syndrome. J Cell Biol 1998; 141:1121-34. [PMID: 9606205 PMCID: PMC2137185 DOI: 10.1083/jcb.141.5.1121] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The Chediak-Higashi syndrome (CHS) is a human recessive autosomal disease caused by mutations in a single gene encoding a protein of unknown function, called lysosomal-trafficking regulator. All cells in CHS patients bear enlarged lysosomes. In addition, T- and natural killer cell cytotoxicity is defective in these patients, causing severe immunodeficiencies. We have analyzed major histocompatibility complex class II functions and intracellular transport in Epstein Barr Virus-transformed B cells from CHS patients. Peptide loading onto major histocompatibility complex class II molecules and antigen presentation are strongly delayed these cells. A detailed electron microscopy analysis of endocytic compartments revealed that only lysosomal multilaminar compartments are enlarged (reaching 1-2 micron), whereas late multivesicular endosomes have normal size and morphology. In contrast to giant multilaminar compartments that bear most of the usual lysosomal markers in these cells (HLA-DR, HLA-DM, Lamp-1, CD63, etc.), multivesicular late endosomes displayed reduced levels of all these molecules, suggesting a defect in transport from the trans-Golgi network and/or early endosomes into late multivesicular endosomes. Further insight into a possible mechanism of this transport defect came from immunolocalizing the lysosomal trafficking regulator protein, as antibodies directed to a peptide from its COOH terminal domain decorated punctated structures partially aligned along microtubules. These results suggest that the product of the Lyst gene is required for sorting endosomal resident proteins into late multivesicular endosomes by a mechanism involving microtubules.
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Affiliation(s)
- W Faigle
- CJF 95-01 INSERM, Institut Curie, 75005 Paris, France
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26
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Raddrizzani L, Bono E, Vogt AB, Kropshofer H, Gallazzi F, Stumiolo T, Hämmerling GJ, Sinigaglia F, Hammer J. Identification of destabilizing residues in an HLA-DM selected M13-displayed peptide repertoire. Immunol Lett 1997. [DOI: 10.1016/s0165-2478(97)85764-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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27
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Abstract
Considerable progress has been made in the field of major histocompatibility complex (MHC) class II-restricted antigen presentation. The analysis of mutant cell lines defective in antigen presentation revealed a central role for the nonclassical MHC class II molecule HLA-DM. Cell biological and biochemical characterization of HLA-DM provided deeper insight into the molecular mechanisms underlying the loading process: HLA-DM accumulates in acidic compartments, where it stabilizes classical class II molecules until a high-stability ligand occupies the class II peptide binding groove. Thus, HLA-DM prevents empty alpha beta dimers from functional inactivation at low endosomal/lysosomal pH in a chaperone-like fashion. In the presence of peptide ligands, HLA-DM acts as a catalyst for peptide loading by releasing CLIP, the residual invariant chain-derived fragment by which the invariant chain is associated with the class II molecules during transport from the endoplasmic reticulum to the loading compartments. Finally, there is accumulating evidence that HLA-DM functions as a peptide editor that removes low-stability ligands, thereby skewing the class II peptide repertoire toward high-stability alpha beta: peptide complexes presentable to T cells.
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Affiliation(s)
- A B Vogt
- Department of Molecular Immunology, German Cancer Research Center, Heidelberg, Germany
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28
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Vergelli M, Hemmer B, Kalbus M, Vogt AB, Ling N, Conlon P, Coligan JE, McFarland H, Martin R. Modifications of peptide ligands enhancing T cell responsiveness imply large numbers of stimulatory ligands for autoreactive T cells. J Immunol 1997; 158:3746-52. [PMID: 9103439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In this report, we demonstrate for autoreactive T cell clones that single amino acid modifications of the antigenic ligand can result in not only abrogated, decreased, or unmodified, but also increased, T cell responsiveness (superagonist ligands). We further studied the effects of combinations of multiple substitutions with different effects in single peptides. Experiments with peptides carrying multiple amino acid exchanges revealed that the final outcome of TCR ligation by a given ligand is the integration of negative, neutral, and positive effects of each single residue. In addition, the introduction of superagonist substitutions together with nonconservative modifications of primary and secondary TCR contacts resulted in stimulatory ligands. These findings indicate that: 1) the specificity of a single TCR is highly degenerate; 2) ligands exist for autoreactive T cells that have higher agonist activity than the autoantigen itself; 3) the rules to search for cross-reactive epitopes in autoimmunity should take into account that amino acids at certain positions within an antigenic peptide may exert superagonist activity and compensate for the negative effects of residues at other positions that would otherwise not be tolerated.
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Affiliation(s)
- M Vergelli
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
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29
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Vergelli M, Hemmer B, Kalbus M, Vogt AB, Ling N, Conlon P, Coligan JE, McFarland H, Martin R. Modifications of peptide ligands enhancing T cell responsiveness imply large numbers of stimulatory ligands for autoreactive T cells. The Journal of Immunology 1997. [DOI: 10.4049/jimmunol.158.8.3746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
In this report, we demonstrate for autoreactive T cell clones that single amino acid modifications of the antigenic ligand can result in not only abrogated, decreased, or unmodified, but also increased, T cell responsiveness (superagonist ligands). We further studied the effects of combinations of multiple substitutions with different effects in single peptides. Experiments with peptides carrying multiple amino acid exchanges revealed that the final outcome of TCR ligation by a given ligand is the integration of negative, neutral, and positive effects of each single residue. In addition, the introduction of superagonist substitutions together with nonconservative modifications of primary and secondary TCR contacts resulted in stimulatory ligands. These findings indicate that: 1) the specificity of a single TCR is highly degenerate; 2) ligands exist for autoreactive T cells that have higher agonist activity than the autoantigen itself; 3) the rules to search for cross-reactive epitopes in autoimmunity should take into account that amino acids at certain positions within an antigenic peptide may exert superagonist activity and compensate for the negative effects of residues at other positions that would otherwise not be tolerated.
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Affiliation(s)
- M Vergelli
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - B Hemmer
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - M Kalbus
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - A B Vogt
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - N Ling
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - P Conlon
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - J E Coligan
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - H McFarland
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - R Martin
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
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30
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Vergelli M, Pinet V, Vogt AB, Kalbus M, Malnati M, Riccio P, Long EO, Martin R. HLA-DR-restricted presentation of purified myelin basic protein is independent of intracellular processing. Eur J Immunol 1997; 27:941-51. [PMID: 9130648 DOI: 10.1002/eji.1830270421] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Antigen presentation to CD4+ T cells involves intracellular antigen processing and loading of peptides onto newly synthesized major histocompatibility complex (MHC)-class II molecules. Some antigens, such as the lipid-bound, native form of myelin basic protein (LB-MBP) can also be presented by recycling of cell surface MHC class II molecules. The data reported here demonstrate that a preparation of highly purified, delipidated MBP (HP-MBP) follows yet another presentation pathway. Similar to LB-MBP, presentation of HP-MBP to HLA-DR1-restricted T cells was independent of HLA-DM, of newly synthesized proteins, and of invariant chain expression. However, in contrast to LB-MBP, presentation of HP-MBP was also independent of internalization of surface HLA-DR molecules. The different requirements for the presentation of the two molecular forms of MBP were further confirmed by use of the protease inhibitor E64: presentation of LB-MBP but not of HP-MBP was inhibited after treatment of target cells with E64. Furthermore, intact HP-MPB bound to isolated HLA-DR molecules in vitro with an association rate that was considerably faster than that of short peptides. These results show that presentation of HP-MBP is independent of intracellular processing and suggest that it may be presented to T cells by direct binding to surface HLA-DR molecules.
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Affiliation(s)
- M Vergelli
- Neuroimmunology Branch, NINDS, NIH, Bethesda, MD 20892-1400, USA
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31
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Abstract
HLA-DM (DM) is a nonclassical MHC class II molecule that interacts with classical MHC II molecules in acidic compartments. During this association DM is supposed to catalyze the release of invariant chain (Ii)-derived CLIP peptides, as well as other peptides bound with low kinetic stability. Here we provide evidence that in lysosomal compartments of B cells a considerable fraction of DM is stably associated with empty DR alphabeta dimers, thereby preventing their functional inactivation and aggregation. Upon encounter with cognate peptide, the DM-associated DR molecules can be rapidly loaded and no longer bind to DM. Thus, DM seems to act as a dedicated class II-specific chaperone. In view of the suggested shortage of DM-resistant self-peptides in the loading compartment, empty class II molecules that are chaperoned by DM may enable the antigen-processing system to respond promptly to the challenge by newly entering antigens.
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Affiliation(s)
- H Kropshofer
- Department of Molecular Immunology, German Cancer Research Center, Heidelberg, Federal Republic of Germany
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32
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Abstract
Loading of classical major histocompatibility complex (MHC) class II molecules with antigen-derived peptides is fast, efficient and highly selective in vivo, quite in contrast to in vitro findings with isolated class II proteins and synthetic peptides. Do accessory proteins speed up the loading process in antigen-presenting cells? Here, a model is presented in which the nonclassical MHC class II molecule HLA-DM plays a pivotal role as a chaperone, catalyst and editor during epitope selection.
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Affiliation(s)
- H Kropshofer
- Dept of Molecular Immunology, German Cancer Research Center, Heidelberg.
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33
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Abstract
During the past five years considerable progress has been made in the field of major histocompatibility complex (MHC) class II-restricted antigen presentation. Several observations made in mutant cell lines with a presentation defect led to the identification of a novel protein, the nonclassic MHC class II molecule human leukocyte antigen (HLA)-DM. Cell biological and biochemical characterization of HLA-DM provided deeper insight into the molecular mechanism underlying the loading process: HLA-DM accumulates in acidic compartments where it binds to classic class II molecules as long as no high-stability ligand occupies the peptide-binding groove. Thus, HLA-DM prevents empty alpha beta dimers from functional inactivation in a chaperone-like fashion. At the same time HLA-DM acts as an editor by removing low-stability ligands, thereby skewing the class II peptide repertoire presentable to T-helper cells.
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Affiliation(s)
- S O Arndt
- Department of Molecular Immunology, German Cancer Research Center, Heildelberg, Germany
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34
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Kropshofer H, Vogt AB, Moldenhauer G, Hammer J, Blum JS, Hämmerling GJ. Editing of the HLA-DR-peptide repertoire by HLA-DM. EMBO J 1996; 15:6144-54. [PMID: 8947036 PMCID: PMC452435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Antigenic peptide loading of classical major histocompatibility complex (MHC) class II molecules requires the exchange of the endogenous invariant chain fragment CLIP (class II associated Ii peptide) for peptides derived from antigenic proteins. This process is facilitated by the non-classical MHC class II molecule HLA-DM (DM) which catalyzes the removal of CLIP. Up to now it has been unclear whether DM releases self-peptides other than CLIP and thereby modifies the peptide repertoire presented to T cells. Here we report that DM can release a variety of peptides from HLA-DR molecules. DR molecules isolated from lymphoblastoid cell lines were found to carry a sizeable fraction of self-peptides that are sensitive to the action of DM. The structural basis for this DM sensitivity was elucidated by high-performance size exclusion chromatography and a novel mass spectrometry binding assay. The results demonstrate that the overall kinetic stability of a peptide bound to DR determines its sensitivity to removal by DM. We show that DM removes preferentially those peptides that contain at least one suboptimal side chain at one of their anchor positions or those that are shorter than 11 residues. These findings provide a rationale for the previously described ligand motifs and the minimal length requirements of naturally processed DR-associated self-peptides. Thus, in endosomal compartments, where peptide loading takes place, DM can function as a versatile peptide editor that selects for high-stability MHC class II-peptide complexes by kinetic proofreading before these complexes are presented to T cells.
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Affiliation(s)
- H Kropshofer
- German Cancer Research Center, Department of Molecular Immunology, Heidelberg, Germany
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35
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Vogt AB, Kropshofer H, Moldenhauer G, Hämmerling GJ. Kinetic analysis of peptide loading onto HLA-DR molecules mediated by HLA-DM. Proc Natl Acad Sci U S A 1996; 93:9724-9. [PMID: 8790398 PMCID: PMC38496 DOI: 10.1073/pnas.93.18.9724] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The nonclassical major histocompatibility complex class II molecule HLA-DM (DM) has recently been shown to play a central role in the class II-associated antigen presentation pathway: DM releases invariant chain-derived CLIP peptides (class II-associated invariant chain protein peptide) from HLA-DR (DR) molecules and thereby facilitates loading with antigenic peptides. Some observations have led to the suggestion that DM acts in a catalytic manner, but so far direct proof is missing. Here, we investigated in vitro the kinetics of exchange of endogenously bound CLIP for various peptides on DR1 and DR2a molecules: we found that in the presence of DM the peptide loading process follows Michaelis-Menten kinetics with turnover numbers of 3-12 DR molecules per minute per DM molecule, and with KM values of 500-1000 nM. In addition, surface plasmon resonance measurements showed that DM interacts efficiently with DR-CLIP complexes but only weakly with DR-peptide complexes isolated from DM-positive cells. Taken together, our data provide evidence that DM functions as an enzyme-like catalyst of peptide exchange and favors the generation of long-lived DR-peptide complexes that are no longer substrates for DM.
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Affiliation(s)
- A B Vogt
- Department of Molecular Immunology, German Cancer Research Center, Heidelberg, Germany
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36
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Pelfrey CM, Tranquill LR, Vogt AB, McFarland HF. T cell response to two immunodominant proteolipid protein (PLP) peptides in multiple sclerosis patients and healthy controls. Mult Scler 1996; 1:270-8. [PMID: 9345429 DOI: 10.1177/135245859600100503] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system in which autoimmune T lymphocytes reacting with myelin antigens are believed to play a pathogenic role. Since HLA binding is involved in the selection of T cell responses, we have examined PLP peptide binding to HLA DR2, an HLA allele frequently found in MS patients. Both PLP 40-60 and PLP 89-106 show significant, high affinity binding to HLA DR2. We then tested whether responses to PLP peptides 40-60 and 89-106 are elevated in multiple sclerosis patients compared to matched controls. We also analysed T cell responses to MBP 87-106, which is considered to be the immunodominant region of MBP in humans. Here we demonstrate heterogenous T cell responses to PLP 40-60, PLP 89-106 and MBP 87-106 in both MS patients and controls. The overall number of TCL and the HLA restriction of those TCL did not vary significantly in the two groups. PLP 40-60 specific cytolytic TCL were increased in MS patients, whereas healthy controls had increased percentages of cytolytic TCL responding to PLP 89-106 and MBP 87-106. Although the data presented here shows heterogenous responses in T cell numbers, differences in numbers and specificity of cytolytic cells could be involved in the pathogenesis of autoimmune demyelinating disease.
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Affiliation(s)
- C M Pelfrey
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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37
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Abstract
The assembly and transport of major histocompatibility complex (MHC) class II molecules require interaction with the invariant chain. A fragment of the invariant chain, CLIP, occupies the peptide-binding groove of the class II molecule. At endosomal pH, the binding of CLIP to human MHC class II HLA-DR molecules was counteracted by its amino-terminal segment (residues 81 to 89), which facilitated rapid release. The CLIP (81-89) fragment also catalyzed the release of CLIP(90-105) and a subset of other self-peptides, probably by transient interaction with an effector site outside the groove. Thus, CLIP may facilitate peptide loading through an allosteric release mechanism.
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Affiliation(s)
- H Kropshofer
- Department of Molecular Immunology, German Cancer Research Center, Heidelberg, Germany
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38
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Vogt AB, Stern LJ, Amshoff C, Dobberstein B, Hämmerling GJ, Kropshofer H. Interference of distinct invariant chain regions with superantigen contact area and antigenic peptide binding groove of HLA-DR. J Immunol 1995; 155:4757-65. [PMID: 7594477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In the endoplasmic reticulum, MHC class II alpha beta dimers associate with the trimeric invariant chain (li), generating a nine-subunit (alpha beta li)3 complex. In the presence of li, the peptide binding groove is blocked, so that loading with self or antigenic peptides can only occur after proteolytic removal of li in specialized post-Golgi compartments. The class II-associated invariant chain peptide region of li (about residues 81-104) is known to mediate binding to class II molecules and blockade of the groove, but this does not exclude additional contact sites for li. Using a set of overlapping li peptides and recombinant soluble li, we demonstrate here that a large segment of li encompassing approximately residues 71 to 128 interacts with HLA-DR molecules. The N- and C-terminal regions of this li segment appear to bind outside the peptide groove to the contact area for the staphylococcal superantigen Staphylococcus aureus enterotoxin B on the alpha 1 domain. The core region of this segment (residues 95-108) prevents binding of antigenic peptides, probably by interaction with the peptide groove. Occupation of the groove with antigenic peptides abolishes binding not only of the core region, but also that of those li peptides that bind outside the groove. These findings suggest the existence of distinct conformational states of class II molecules, with li binding preferentially to one form.
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Affiliation(s)
- A B Vogt
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
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39
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Vogt AB, Stern LJ, Amshoff C, Dobberstein B, Hämmerling GJ, Kropshofer H. Interference of distinct invariant chain regions with superantigen contact area and antigenic peptide binding groove of HLA-DR. The Journal of Immunology 1995. [DOI: 10.4049/jimmunol.155.10.4757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
In the endoplasmic reticulum, MHC class II alpha beta dimers associate with the trimeric invariant chain (li), generating a nine-subunit (alpha beta li)3 complex. In the presence of li, the peptide binding groove is blocked, so that loading with self or antigenic peptides can only occur after proteolytic removal of li in specialized post-Golgi compartments. The class II-associated invariant chain peptide region of li (about residues 81-104) is known to mediate binding to class II molecules and blockade of the groove, but this does not exclude additional contact sites for li. Using a set of overlapping li peptides and recombinant soluble li, we demonstrate here that a large segment of li encompassing approximately residues 71 to 128 interacts with HLA-DR molecules. The N- and C-terminal regions of this li segment appear to bind outside the peptide groove to the contact area for the staphylococcal superantigen Staphylococcus aureus enterotoxin B on the alpha 1 domain. The core region of this segment (residues 95-108) prevents binding of antigenic peptides, probably by interaction with the peptide groove. Occupation of the groove with antigenic peptides abolishes binding not only of the core region, but also that of those li peptides that bind outside the groove. These findings suggest the existence of distinct conformational states of class II molecules, with li binding preferentially to one form.
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Affiliation(s)
- A B Vogt
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
| | - L J Stern
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
| | - C Amshoff
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
| | - B Dobberstein
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
| | - G J Hämmerling
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
| | - H Kropshofer
- German Cancer Research Center, Tumorimmunology Program, Heidelberg, Germany
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40
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Kropshofer H, Vogt AB, Hämmerling GJ. Structural features of the invariant chain fragment CLIP controlling rapid release from HLA-DR molecules and inhibition of peptide binding. Proc Natl Acad Sci U S A 1995; 92:8313-7. [PMID: 7667286 PMCID: PMC41147 DOI: 10.1073/pnas.92.18.8313] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The invariant chain (Ii) prevents binding of ligands to major histocompatibility complex (MHC) class II molecules in the endoplasmic reticulum and during intracellular transport. Stepwise removal of the Ii in a trans-Golgi compartment renders MHC class II molecules accessible for peptide loading, with CLIP (class II-associated Ii peptides) as the final fragment to be released. Here we show that CLIP can be subdivided into distinct functional regions. The C-terminal segment (residues 92-105) of the CLIP-(81-105) fragment mediates inhibition of self- and antigenic peptide binding to HLA-DR2 molecules. In contrast, the N-terminal segment CLIP-(81-98) binds to the Staphylococcus aureus enterotoxin B contact site outside the peptide-binding groove on the alpha 1 domain and does not interfere with peptide binding. Its functional significance appears to lie in the contribution to CLIP removal: the dissociation of CLIP-(81-105) is characterized by a fast off-rate, which is accelerated at endosomal pH, whereas in the absence of the N-terminal CLIP-(81-91), the off-rate of C-terminal CLIP-(92-105) is slow and remains unaltered at low pH. Mechanistically, the N-terminal segment of CLIP seems to prevent tight interactions of CLIP side chains with specificity pockets in the peptide-binding groove that normally occurs during maturation of long-lived class II-peptide complexes.
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Affiliation(s)
- H Kropshofer
- Tumor Immunology Program, German Cancer Research Center, Heidelberg
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41
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Vogt AB, Kropshofer H, Kalbacher H, Kalbus M, Rammensee HG, Coligan JE, Martin R. Ligand motifs of HLA-DRB5*0101 and DRB1*1501 molecules delineated from self-peptides. The Journal of Immunology 1994. [DOI: 10.4049/jimmunol.153.4.1665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Antigenic peptides are presented to CD4+ T cells by MHC class II molecules via a highly polymorphic peptide-binding groove. The two HLA-DR alleles isotypically expressed on HLA-DR15Dw2-positive cells, DRB1*1501 (DR2b) and DRB5*0101 (DR2a) molecules, show a number of differences in polymorphic residues of the beta-chain, including the Gly-Val-dimorphism at position beta 86. Therefore, different requirements for interaction of peptides with these alleles must be expected. In this study, naturally processed self-peptides were eluted from purified HLA-DR15Dw2 molecules and related to DRB1*1501 or DRB5*0101 molecules by binding assays. An alignment of self-peptides and foreign peptides allowed the delineation of putative anchor motifs. N- and C-terminally truncated and alanine-substituted derivatives of the DR15Dw2 restricted myelin basic protein epitope MBP(85-105) confirmed their validity. Thus, DRB5*0101 requires a bulky hydrophobic residue (F or Y) at position i as a primary anchor, and Q or an aliphatic residue, such as V, I, or M, at position i + 3; positively charged residues at positions i + 7 and i + 8 are secondary anchors. For DRB1*1501, a nonaromatic, hydrophobic anchor (L, V, or I) at position i is supplemented by a bulky hydrophobic residue (F or Y) at position i + 3 as primary anchor; an additional hydrophobic side chain represented by M, I, V, or F occurs at position i + 6. Therefore, MBP(85-105) seems to contain two MHC interaction sites for DRB1*1501 and DRB5*0101, respectively, that may contribute to its immunodominance. Because HLA-DR15 Dw2 is associated with susceptibility to develop multiple sclerosis, the delineation of ligand motifs of the two DR2 alleles may help to study the interaction between potential autoantigenic peptides and these molecules in the future.
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Affiliation(s)
- A B Vogt
- Center of Medical and Natural Sciences, University of Tübingen, Germany
| | - H Kropshofer
- Center of Medical and Natural Sciences, University of Tübingen, Germany
| | - H Kalbacher
- Center of Medical and Natural Sciences, University of Tübingen, Germany
| | - M Kalbus
- Center of Medical and Natural Sciences, University of Tübingen, Germany
| | - H G Rammensee
- Center of Medical and Natural Sciences, University of Tübingen, Germany
| | - J E Coligan
- Center of Medical and Natural Sciences, University of Tübingen, Germany
| | - R Martin
- Center of Medical and Natural Sciences, University of Tübingen, Germany
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Vogt AB, Kropshofer H, Kalbacher H, Kalbus M, Rammensee HG, Coligan JE, Martin R. Ligand motifs of HLA-DRB5*0101 and DRB1*1501 molecules delineated from self-peptides. J Immunol 1994; 153:1665-73. [PMID: 7519208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Antigenic peptides are presented to CD4+ T cells by MHC class II molecules via a highly polymorphic peptide-binding groove. The two HLA-DR alleles isotypically expressed on HLA-DR15Dw2-positive cells, DRB1*1501 (DR2b) and DRB5*0101 (DR2a) molecules, show a number of differences in polymorphic residues of the beta-chain, including the Gly-Val-dimorphism at position beta 86. Therefore, different requirements for interaction of peptides with these alleles must be expected. In this study, naturally processed self-peptides were eluted from purified HLA-DR15Dw2 molecules and related to DRB1*1501 or DRB5*0101 molecules by binding assays. An alignment of self-peptides and foreign peptides allowed the delineation of putative anchor motifs. N- and C-terminally truncated and alanine-substituted derivatives of the DR15Dw2 restricted myelin basic protein epitope MBP(85-105) confirmed their validity. Thus, DRB5*0101 requires a bulky hydrophobic residue (F or Y) at position i as a primary anchor, and Q or an aliphatic residue, such as V, I, or M, at position i + 3; positively charged residues at positions i + 7 and i + 8 are secondary anchors. For DRB1*1501, a nonaromatic, hydrophobic anchor (L, V, or I) at position i is supplemented by a bulky hydrophobic residue (F or Y) at position i + 3 as primary anchor; an additional hydrophobic side chain represented by M, I, V, or F occurs at position i + 6. Therefore, MBP(85-105) seems to contain two MHC interaction sites for DRB1*1501 and DRB5*0101, respectively, that may contribute to its immunodominance. Because HLA-DR15 Dw2 is associated with susceptibility to develop multiple sclerosis, the delineation of ligand motifs of the two DR2 alleles may help to study the interaction between potential autoantigenic peptides and these molecules in the future.
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Affiliation(s)
- A B Vogt
- Center of Medical and Natural Sciences, University of Tübingen, Germany
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Martin R, Vogt AB, Kropshofer H, Lichtenfels R. Association of HLA and multiple sclerosis. Behring Inst Mitt 1994:158-170. [PMID: 7998908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Multiple Sclerosis (MS) is a demyelinating disease of the central nervous system. Although the cause of MS is still unknown, it is considered an autoimmune disease based on the composition of inflammatory infiltrates in the brain and on parallels with a T-cell-mediated animal model of demyelinating diseases called experimental allergic encephalomyelitis (EAE). Similar to other autoimmune diseases, the immunogenetic background, in particular the MHC/HLA type, contributes to susceptibility. This review summarizes the current knowledge about the association between HLA background and MS as well as immunological findings in EAE and MS. Finally, an attempt is made to explain how structural interactions between disease-associated HLA type and binding of an autoantigenic peptide could relate to disease.
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Affiliation(s)
- R Martin
- Neurologische Universitätsklinik, Universität Tübingen, Germany
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Lichtenfels R, Biddison WE, Schulz H, Vogt AB, Martin R. CARE-LASS (calcein-release-assay), an improved fluorescence-based test system to measure cytotoxic T lymphocyte activity. J Immunol Methods 1994; 172:227-39. [PMID: 7518485 DOI: 10.1016/0022-1759(94)90110-4] [Citation(s) in RCA: 218] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
CARE-LASS is a highly sensitive, fast, simple and safe fluorometric microassay. Target cells are loaded with acetoxymethyl ester of calcein (calcein-AM) that passively crosses the cell membrane. Intracellular esterases convert the molecule to calcein, a polar fluorochrome which, in cells with intact plasma membranes, displays good retention characteristics and low pH sensitivity. In analogy to standard 51Cr release assays, the CARE-LASS system is based on the release of a marker into the supernatant that is measured by an automated fluorescence scanner and correlates with the number of lysed cells. We tested the CARE-LASS system by measuring cytotoxicity in major histocompatibility complex (MHC) class I and MHC class II restricted cytotoxic T lymphocyte (CTL) assays as well as lymphokine activated killer (LAK) mediated cytotoxicity. We applied a small set of target cell lines at various effector to target (E:T) ratios, at different antigen concentrations and compared CARE-LASS CTL data to data resulting from conventional 51Cr release assays. The CARE-LASS system provides a reliable and sensitive method to measure cell-mediated cytotoxicity.
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Affiliation(s)
- R Lichtenfels
- Department of Neurology, Medical School, University of Tübingen, Germany
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Lehmacher A, Vogt AB, Hensel R. Biosynthesis of cyclic 2,3-diphosphoglycerate. Isolation and characterization of 2-phosphoglycerate kinase and cyclic 2,3-diphosphoglycerate synthetase from Methanothermus fervidus. FEBS Lett 1990; 272:94-8. [PMID: 2226838 DOI: 10.1016/0014-5793(90)80456-s] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Starting from 2-phosphoglycerate the biosynthesis of cDPG comprises two steps: (i) the phosphorylation of 2-phosphoglycerate to 2,3-diphosphoglycerate and (ii) the intramolecular cyclization to cyclic 2,3-diphosphoglycerate. The involved enzymes, 2-phosphoglycerate kinase and cyclic 2,3-diphosphoglycerate synthetase, were purified form Methanothermus fervidus. Their molecular and catalytic properties were characterized.
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Affiliation(s)
- A Lehmacher
- Max-Planck-Institut für Biochemie, Martinsried, FRG
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