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Shahbazy M, Ramarathinam SH, Li C, Illing PT, Faridi P, Croft NP, Purcell AW. MHCpLogics: an interactive machine learning-based tool for unsupervised data visualization and cluster analysis of immunopeptidomes. Brief Bioinform 2024; 25:bbae087. [PMID: 38487848 PMCID: PMC10940831 DOI: 10.1093/bib/bbae087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 12/12/2023] [Accepted: 02/15/2024] [Indexed: 03/18/2024] Open
Abstract
The major histocompatibility complex (MHC) encodes a range of immune response genes, including the human leukocyte antigens (HLAs) in humans. These molecules bind peptide antigens and present them on the cell surface for T cell recognition. The repertoires of peptides presented by HLA molecules are termed immunopeptidomes. The highly polymorphic nature of the genres that encode the HLA molecules confers allotype-specific differences in the sequences of bound ligands. Allotype-specific ligand preferences are often defined by peptide-binding motifs. Individuals express up to six classical class I HLA allotypes, which likely present peptides displaying different binding motifs. Such complex datasets make the deconvolution of immunopeptidomic data into allotype-specific contributions and further dissection of binding-specificities challenging. Herein, we developed MHCpLogics as an interactive machine learning-based tool for mining peptide-binding sequence motifs and visualization of immunopeptidome data across complex datasets. We showcase the functionalities of MHCpLogics by analyzing both in-house and published mono- and multi-allelic immunopeptidomics data. The visualization modalities of MHCpLogics allow users to inspect clustered sequences down to individual peptide components and to examine broader sequence patterns within multiple immunopeptidome datasets. MHCpLogics can deconvolute large immunopeptidome datasets enabling the interrogation of clusters for the segregation of allotype-specific peptide sequence motifs, identification of sub-peptidome motifs, and the exportation of clustered peptide sequence lists. The tool facilitates rapid inspection of immunopeptidomes as a resource for the immunology and vaccine communities. MHCpLogics is a standalone application available via an executable installation at: https://github.com/PurcellLab/MHCpLogics.
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Affiliation(s)
- Mohammad Shahbazy
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
| | - Chen Li
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
| | - Patricia T Illing
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
| | - Pouya Faridi
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia
- Monash Proteomics and Metabolomics Platform, Department of Medicine, School of Clinical Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Nathan P Croft
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
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Wang SS, Pandey K, Watson KA, Abbott RC, Mifsud NA, Gracey FM, Ramarathinam SH, Cross RS, Purcell AW, Jenkins MR. Endogenous H3.3K27M derived peptide restricted to HLA-A∗02:01 is insufficient for immune-targeting in diffuse midline glioma. Mol Ther Oncolytics 2023; 30:167-180. [PMID: 37674626 PMCID: PMC10477804 DOI: 10.1016/j.omto.2023.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 08/11/2023] [Indexed: 09/08/2023] Open
Abstract
Diffuse midline glioma (DMG) is a childhood brain tumor with an extremely poor prognosis. Chimeric antigen receptor (CAR) T cell therapy has recently demonstrated some success in DMG, but there may a need to target multiple tumor-specific targets to avoid antigen escape. We developed a second-generation CAR targeting an HLA-A∗02:01 restricted histone 3K27M epitope in DMG, the target of previous peptide vaccination and T cell receptor-mimics. These CAR T cells demonstrated specific, titratable, binding to cells pulsed with the H3.3K27M peptide. However, we were unable to observe scFv binding, CAR T cell activation, or cytotoxic function against H3.3K27M+ patient-derived models. Despite using sensitive immunopeptidomics, we could not detect the H3.3K27M26-35-HLA-A∗02:01 peptide on these patient-derived models. Interestingly, other non-mutated peptides from DMG were detected bound to HLA-A∗02:01 and other class I molecules, including a novel HLA-A3-restricted peptide encompassing the K27M mutation and overlapping with the H3 K27M26-35-HLA-A∗02:01 peptide. These results suggest that targeting the H3 K27M26-35 mutation in context of HLA-A∗02:01 may not be a feasible immunotherapy strategy because of its lack of presentation. These findings should inform future investigations and clinical trials in DMG.
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Affiliation(s)
- Stacie S. Wang
- The Walter and Eliza Hall Institute of Medical Research, Immunology Division, Parkville, VIC 3052, Australia
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- The University of Melbourne, Department of Medical Biology, Parkville, VIC 3052, Australia
| | - Kirti Pandey
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Katherine A. Watson
- The Walter and Eliza Hall Institute of Medical Research, Immunology Division, Parkville, VIC 3052, Australia
| | - Rebecca C. Abbott
- The Walter and Eliza Hall Institute of Medical Research, Immunology Division, Parkville, VIC 3052, Australia
- The University of Melbourne, Department of Medical Biology, Parkville, VIC 3052, Australia
| | - Nicole A. Mifsud
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Fiona M. Gracey
- Myrio Therapeutics, 6-16 Joseph St, Blackburn North, Melbourne, VIC 3130, Australia
| | - Sri H. Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Ryan S. Cross
- The Walter and Eliza Hall Institute of Medical Research, Immunology Division, Parkville, VIC 3052, Australia
| | - Anthony W. Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Misty R. Jenkins
- The Walter and Eliza Hall Institute of Medical Research, Immunology Division, Parkville, VIC 3052, Australia
- The University of Melbourne, Department of Medical Biology, Parkville, VIC 3052, Australia
- La Trobe University, La Trobe Institute for Molecular Science, Bundoora, VIC, Australia
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Pandey K, Wang SS, Mifsud NA, Faridi P, Davenport AJ, Webb AI, Sandow JJ, Ayala R, Monje M, Cross RS, Ramarathinam SH, Jenkins MR, Purcell AW. A combined immunopeptidomics, proteomics, and cell surface proteomics approach to identify immunotherapy targets for diffuse intrinsic pontine glioma. Front Oncol 2023; 13:1192448. [PMID: 37637064 PMCID: PMC10455951 DOI: 10.3389/fonc.2023.1192448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 07/19/2023] [Indexed: 08/29/2023] Open
Abstract
Introduction Diffuse intrinsic pontine glioma (DIPG), recently reclassified as a subtype of diffuse midline glioma, is a highly aggressive brainstem tumor affecting children and young adults, with no cure and a median survival of only 9 months. Conventional treatments are ineffective, highlighting the need for alternative therapeutic strategies such as cellular immunotherapy. However, identifying unique and tumor-specific cell surface antigens to target with chimeric antigen receptor (CAR) or T-cell receptor (TCR) therapies is challenging. Methods In this study, a multi-omics approach was used to interrogate patient-derived DIPG cell lines and to identify potential targets for immunotherapy. Results Through immunopeptidomics, a range of targetable peptide antigens from cancer testis and tumor-associated antigens as well as peptides derived from human endogenous retroviral elements were identified. Proteomics analysis also revealed upregulation of potential drug targets and cell surface proteins such as Cluster of differentiation 27 (CD276) B7 homolog 3 protein (B7H3), Interleukin 13 alpha receptor 2 (IL-13Rα2), Human Epidermal Growth Factor Receptor 3 (HER2), Ephrin Type-A Receptor 2 (EphA2), and Ephrin Type-A Receptor 3 (EphA3). Discussion The results of this study provide a valuable resource for the scientific community to accelerate immunotherapeutic approaches for DIPG. Identifying potential targets for CAR and TCR therapies could open up new avenues for treating this devastating disease.
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Affiliation(s)
- Kirti Pandey
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Stacie S. Wang
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Children’s Cancer Centre, Royal Children’s Hospital, Parkville, VIC, Australia
| | - Nicole A. Mifsud
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Pouya Faridi
- Monash Proteomics and Metabolomics Facility, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- School of Clinical Sciences, Department of Medicine, Monash University, Clayton, VIC, Australia
- Department of Medicine, Sub-Faculty of Clinical and Molecular Medicine, Faculty of Medicine, Nursing & Health Sciences, Monash University, Clayton, VIC, Australia
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Molecular and Translational Medicine, School of Medicine, Nursing and Health Sciences, Monash University, Clayton, VIC, Australia
| | - Alexander J. Davenport
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Andrew I. Webb
- Advanced Technology and Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Jarrod J. Sandow
- Advanced Technology and Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Rochelle Ayala
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Michelle Monje
- Department of Neurology and Neurological Sciences and Howard Hughes Medical Institute, Stanford University, Stanford, CA, United States
| | - Ryan S. Cross
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Sri H. Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Misty R. Jenkins
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- The Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
- LaTrobe Institute for Molecular Science, LaTrobe University, Bundoora, VIC, Australia
| | - Anthony W. Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
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Shahbazy M, Ramarathinam SH, Illing PT, Jappe EC, Faridi P, Croft NP, Purcell AW. Benchmarking bioinformatics pipelines in data-independent acquisition mass spectrometry for immunopeptidomics. Mol Cell Proteomics 2023; 22:100515. [PMID: 36796644 PMCID: PMC10060114 DOI: 10.1016/j.mcpro.2023.100515] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 01/26/2023] [Accepted: 02/06/2023] [Indexed: 02/16/2023] Open
Abstract
Immunopeptidomes are the peptide repertoires bound by the molecules encoded by the major histocompatibility complex (MHC) (human leukocyte antigen (HLA) in humans). These HLA-peptide complexes are presented on the cell surface for immune T-cell recognition. Immunopeptidomics denotes the utilization of tandem mass spectrometry (MS/MS) to identify and quantify peptides bound to HLA molecules. Data-independent acquisition (DIA) has emerged as a powerful strategy for quantitative proteomics and deep proteome-wide identification; however, DIA application to immunopeptidomics analyses has so far seen limited use. Further, of the many DIA data processing tools currently available, there is no consensus in the immunopeptidomics community on the most appropriate pipeline(s) for in-depth and accurate HLA peptide identification. Herein, we benchmarked four commonly used spectral library-based DIA pipelines developed for proteomics applications (Skyline, Spectronaut, DIA-NN, and PEAKS) for their ability to perform immunopeptidome quantification. We validated and assessed the capability of each tool to identify and quantify HLA-bound peptides. Generally, DIA-NN and PEAKS provided higher immunopeptidome coverage with more reproducible results. Skyline and Spectronaut conferred more accurate peptide identification with lower experimental false-positive rates. All tools demonstrated reasonable correlations in quantifying precursors of HLA-bound peptides. Our benchmarking study suggests a combined strategy of applying at least two complementary DIA software tools to achieve the greatest degree of confidence and in-depth coverage of immunopeptidome data.
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Affiliation(s)
- Mohammad Shahbazy
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Sri H Ramarathinam
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Patricia T Illing
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Emma C Jappe
- Evaxion Biotech, Bredgade 34E, DK-1260 Copenhagen, Denmark
| | - Pouya Faridi
- Department of Medicine, School of Clinical Sciences, Monash University, Clayton, VIC 3800, Australia.
| | - Nathan P Croft
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Anthony W Purcell
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
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Ramarathinam SH, Faridi P, Peng A, Szeto P, Wong NC, Behren A, Shackleton M, Purcell AW. Abstract 1373: PeptidePCR: Direct identification of cancer vaccine targets from scant clinical samples. Cancer Res 2022. [DOI: 10.1158/1538-7445.am2022-1373] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Peptides presented by Human Leukocyte antigen (HLA) class I and II molecules form an important component of the adaptive immune response against tumors. Identifying HLA-bound peptides is therefore crucial to understand the specificity of T cell responses in cancer. Due to sample limitations, it is often difficult or impossible to confirm epitope presentation in clinical biopsy material. To develop truly personal medicine, target epitopes need to be directly identified or validated in patient tumors at the peptide antigen level.
Methodology: We have developed a microscale HLA immunoprecipitation protocol which when combined with a tandem mass tag (TMT)-based barcoding approach was able to identify HLA-bound peptides. HLA-complexes were affinity purified from either cultured cells, patient-derived xenograft or melanoma biopsies and the peptide cargo was tagged using TMT barcodes and analyzed using high-resolution mass spectrometry. Like primers in PCR, the carrier peptides and multiplexing of samples amplifies the signal enabling sensitive detection.
Results: By using this strategy, we identified HLA-bound peptides from as few as ~1000 cultured cells. We demonstrate the clinical utility of this approach by confirming the presentation of around 1000 peptides from a challenging melanoma biopsy (~1-20mg in total), including 11 well-known T-cell response-inducing epitopes and other potential epitopes derived from Melanoma-associated antigens and neoantigens.
Conclusion: This strategy will be useful for studying peptidome subsets in other clinical samples where the amount of tissue available via sampling is limiting, including biopsies taken for autoimmune diseases and infections, or to sample rare cell types in tissue/cell samples, such as different antigen-presenting cell subsets. The approach can directly isolate antigens that are already presented by HLA molecules, thereby increasing the precision of personalized approaches to cancer treatment with less than 1-week turnaround times.
Citation Format: Sri H. Ramarathinam, Pouya Faridi, Angela Peng, Pacman Szeto, Nicholas C. Wong, Andreas Behren, Mark Shackleton, Anthony W. Purcell. PeptidePCR: Direct identification of cancer vaccine targets from scant clinical samples [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1373.
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Affiliation(s)
| | - Pouya Faridi
- 1Monash University, Clayton, Victoria, Australia
| | - Angela Peng
- 2Monash University and Alfred Health, Clayton, Victoria, Australia
| | - Pacman Szeto
- 2Monash University and Alfred Health, Clayton, Victoria, Australia
| | | | - Andreas Behren
- 3Olivia Newton-John Cancer Research Institute and La Trobe University, Heidelberg, Victoria, Australia
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Illing PT, Ramarathinam SH, Purcell AW. New insights and approaches for analyses of immunopeptidomes. Curr Opin Immunol 2022; 77:102216. [PMID: 35716458 DOI: 10.1016/j.coi.2022.102216] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/10/2022] [Indexed: 11/03/2022]
Abstract
Human leucocyte antigen (HLA) molecules play a key role in health and disease by presenting antigen to T-lymphocytes for immunosurveillance. Immunopeptidomics involves the study of the collection of peptides presented within the antigen-binding groove of HLA molecules. Identifying their nature and diversity is crucial to understanding immunosurveillance especially during infection or for the recognition and potential eradication of tumours. This review discusses recent advances in the isolation, identification, and quantitation of these peptide antigens. New informatics approaches and databases have shed light on the extent of peptide antigens derived from unconventional sources including peptides derived from transcripts associated with frame shifts, long noncoding RNA, incorrectly annotated untranslated regions, post-translational modifications, and proteasomal splicing. Several challenges remain in successful analysis of immunopeptides, yet recent developments point to unexplored biology waiting to be unravelled.
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Affiliation(s)
- Patricia T Illing
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.
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Kim ML, Hardy MY, Edgington-Mitchell LE, Ramarathinam SH, Chung SZ, Russell AK, Currie I, Sleebs BE, Purcell AW, Tye-Din JA, Wicks IP. Hydroxychloroquine inhibits the mitochondrial antioxidant system in activated T cells. iScience 2021; 24:103509. [PMID: 34934928 DOI: 10.1016/j.isci.2021.103509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/15/2021] [Accepted: 11/20/2021] [Indexed: 12/30/2022] Open
Abstract
Although hydroxychloroquine (HCQ) has long been used to treat autoimmune diseases, its mechanism of action remains poorly understood. In CD4 T-cells, we found that a clinically relevant concentration of HCQ inhibited the mitochondrial antioxidant system triggered by TCR crosslinking, leading to increased mitochondrial superoxide, impaired activation-induced autophagic flux, and reduced proliferation of CD4 T-cells. In antigen-presenting cells, HCQ also reduced constitutive activation of the endo-lysosomal protease legumain and toll-like receptor 9, thereby reducing cytokine production, but it had little apparent impact on constitutive antigen processing and peptide presentation. HCQ's effects did not require endo-lysosomal pH change, nor impaired autophagosome-lysosome fusion. We explored the clinical relevance of these findings in patients with celiac disease-a prototypic CD4 T-cell-mediated disease-and found that HCQ limits ex vivo antigen-specific T cell responses. We report a T-cell-intrinsic immunomodulatory effect from HCQ and suggest potential re-purposing of HCQ for celiac disease.
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Affiliation(s)
- Man Lyang Kim
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Melinda Y Hardy
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Laura E Edgington-Mitchell
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3052, Australia.,Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia.,Department of Oral and Maxillofacial Surgery, New York University College of Dentistry, Bluestone Center for Clinical Research, New York, NY 10010, USA
| | - Sri H Ramarathinam
- Infection and Immunity Program and The Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, Clayton, VIC 3800, Australia
| | - Shan Zou Chung
- Infection and Immunity Program and The Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, Clayton, VIC 3800, Australia
| | - Amy K Russell
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia
| | - Iain Currie
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Brad E Sleebs
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Anthony W Purcell
- Infection and Immunity Program and The Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, Clayton, VIC 3800, Australia
| | - Jason A Tye-Din
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia.,Gastroenterology Department, Royal Melbourne Hospital, Parkville, VIC 3052, Australia
| | - Ian P Wicks
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia.,Rheumatology Unit, Royal Melbourne Hospital, Parkville, VIC 3052, Australia
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Owen RS, Ramarathinam SH, Bailey A, Gastaldello A, Hussey K, Skipp PJ, Purcell AW, Siddle HV. The differentiation state of the Schwann cell progenitor drives phenotypic variation between two contagious cancers. PLoS Pathog 2021; 17:e1010033. [PMID: 34780568 PMCID: PMC8629380 DOI: 10.1371/journal.ppat.1010033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 07/20/2021] [Revised: 11/29/2021] [Accepted: 10/13/2021] [Indexed: 01/04/2023] Open
Abstract
Contagious cancers are a rare pathogenic phenomenon in which cancer cells gain the ability to spread between genetically distinct hosts. Nine examples have been identified across marine bivalves, dogs and Tasmanian devils, but the Tasmanian devil is the only mammalian species known to have given rise to two distinct lineages of contagious cancer, termed Devil Facial Tumour 1 (DFT1) and 2 (DFT2). Remarkably, DFT1 and DFT2 arose independently from the same cell type, a Schwann cell, and while their ultra-structural features are highly similar they exhibit variation in their mutational signatures and infection dynamics. As such, DFT1 and DFT2 provide a unique framework for investigating how a common progenitor cell can give rise to distinct contagious cancers. Using a proteomics approach, we show that DFT1 and DFT2 are derived from Schwann cells in different differentiation states, with DFT2 carrying a molecular signature of a less well differentiated Schwann cell. Under inflammatory signals DFT1 and DFT2 have different gene expression profiles, most notably involving Schwann cell markers of differentiation, reflecting the influence of their distinct origins. Further, DFT2 cells express immune cell markers typically expressed during nerve repair, consistent with an ability to manipulate their extracellular environment, facilitating the cell’s ability to transmit between individuals. The emergence of two contagious cancers in the Tasmanian devil suggests that the inherent plasticity of Schwann cells confers a vulnerability to the formation of contagious cancers. Cancer can be an infectious pathogen, with nine known cases, infecting bivalves, dogs and two independent tumours circulating in the endangered Tasmanian devil. These cancers, known as Devil Facial Tumour 1 (DFT1) and Devil Facial Tumour 2 (DFT2), spread through the wild population much like parasites, moving between genetically distinct hosts during social biting behaviours and persisting in the population. As DFT1 and DFT2 are independent contagious cancers that arose from the same cell type, a Schwann cell, they provide a unique model system for studying the emergence of phenotypic variation in cancers derived from a single progenitor cell. In this study, we have shown that these two remarkably similar tumours have emerged from Schwann cells in different differentiation states. The differentiation state of the progenitor has altered the characteristics of each tumour, resulting in different responses to external signals. This work demonstrates that the cellular origin of infection can direct the phenotype of a contagious cancer and how it responds to signals from the host environment. Further, the plasticity of Schwann cells may make these cells more prone to forming contagious cancers, raising the possibility that further parasitic cancers could emerge from this cell type.
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Affiliation(s)
- Rachel S. Owen
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Sri H. Ramarathinam
- Department of Biochemistry and Molecular Biology and the Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Alistair Bailey
- Centre for Cancer Immunology, University of Southampton, Southampton, United Kingdom
- Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Annalisa Gastaldello
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Kathryn Hussey
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Paul J. Skipp
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
- Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Anthony W. Purcell
- Department of Biochemistry and Molecular Biology and the Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Hannah V. Siddle
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
- Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
- * E-mail:
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Son ET, Faridi P, Paul-Heng M, Leong ML, English K, Ramarathinam SH, Braun A, Dudek NL, Alexander IE, Lisowski L, Bertolino P, Bowen DG, Purcell AW, Mifsud NA, Sharland AF. The self-peptide repertoire plays a critical role in transplant tolerance induction. J Clin Invest 2021; 131:e146771. [PMID: 34428180 DOI: 10.1172/jci146771] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 08/18/2021] [Indexed: 11/17/2022] Open
Abstract
While direct allorecognition underpins both solid organ allograft rejection and tolerance induction, the specific molecular targets of most directly alloreactive CD8+ T cells have not been defined. In this study, we used a combination of genetically engineered major histocompatibility complex class I (MHC I) constructs, mice with a hepatocyte-specific mutation in the class I antigen-presentation pathway, and immunopeptidomic analysis to provide definitive evidence for the contribution of the peptide cargo of allogeneic MHC I molecules to transplant tolerance induction. We established a systematic approach for the discovery of directly recognized pMHC epitopes and identified 17 strongly immunogenic H-2Kb-associated peptides recognized by CD8+ T cells from B10.BR (H-2k) mice, 13 of which were also recognized by BALB/c (H-2d) mice. As few as 5 different tetramers used together were able to identify a high proportion of alloreactive T cells within a polyclonal population, suggesting that there are immunodominant allogeneic MHC-peptide complexes that can account for a large component of the alloresponse.
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Affiliation(s)
- Eric T Son
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Pouya Faridi
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Moumita Paul-Heng
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Mario L Leong
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Kieran English
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Sri H Ramarathinam
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Asolina Braun
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nadine L Dudek
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Ian E Alexander
- Gene Therapy Research Unit, Children's Medical Research Institute, The University of Sydney, Faculty of Medicine and Health and Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,The University of Sydney, Sydney Medical School, Discipline of Child and Adolescent Health, Westmead, New South Wales, Australia
| | - Leszek Lisowski
- Translational Vectorology Research Unit, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, Australia.,Vector and Genome Engineering Facility, Children's Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, Australia.,Military Institute of Medicine, Laboratory of Molecular Oncology and Innovative Therapies, Warsaw, Poland
| | - Patrick Bertolino
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - David G Bowen
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia.,Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Anthony W Purcell
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nicole A Mifsud
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Alexandra F Sharland
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
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10
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Ramarathinam SH, Purcell AW. Proteomics special issue: Precision immunology and oncology. Proteomics 2021; 21:e2000159. [PMID: 34510736 DOI: 10.1002/pmic.202000159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 08/12/2021] [Indexed: 11/09/2022]
Affiliation(s)
- Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and the Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and the Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
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11
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Scull KE, Pandey K, Ramarathinam SH, Purcell AW. Immunopeptidogenomics: Harnessing RNA-Seq to Illuminate the Dark Immunopeptidome. Mol Cell Proteomics 2021; 20:100143. [PMID: 34509645 PMCID: PMC8724885 DOI: 10.1016/j.mcpro.2021.100143] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 08/10/2021] [Accepted: 08/24/2021] [Indexed: 01/08/2023] Open
Abstract
Human leukocyte antigen (HLA) molecules are cell-surface glycoproteins that present peptide antigens on the cell surface for surveillance by T lymphocytes, which contemporaneously seek signs of disease. Mass spectrometric analysis allows us to identify large numbers of these peptides (the immunopeptidome) following affinity purification of solubilized HLA-peptide complexes. However, in recent years, there has been a growing awareness of the "dark side" of the immunopeptidome: unconventional peptide epitopes, including neoepitopes, which elude detection by conventional search methods because their sequences are not present in reference protein databases (DBs). Here, we establish a bioinformatics workflow to aid identification of peptides generated by noncanonical translation of mRNA or by genome variants. The workflow incorporates both standard transcriptomics software and novel computer programs to produce cell line-specific protein DBs based on three-frame translation of the transcriptome. The final protein DB also includes sequences resulting from variants determined by variant calling on the same RNA-Seq data. We then searched our experimental data against both transcriptome-based and standard DBs using PEAKS Studio (Bioinformatics Solutions, Inc). Finally, further novel software helps to compare the various result sets arising for each sample, pinpoint putative genomic origins for unconventional sequences, and highlight potential neoepitopes. We applied the workflow to study the immunopeptidome of the acute myeloid leukemia cell line THP-1, using RNA-Seq and immunopeptidome data. We confidently identified over 14,000 peptides from three replicates of purified HLA peptides derived from THP-1 cells using the conventional UniProt human proteome. Using the transcriptome-based DB generated using our workflow, we recapitulated >85% of these and also identified 1029 unconventional peptides not explained by UniProt, including 16 sequences caused by nonsynonymous variants. Our workflow, which we term "immunopeptidogenomics," can provide DBs, which include pertinent unconventional sequences and allow neoepitope discovery, without becoming too large to search. Immunopeptidogenomics is a step toward unbiased search approaches that are needed to illuminate the dark side of the immunopeptidome.
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Affiliation(s)
- Katherine E Scull
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Kirti Pandey
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
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12
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Ramarathinam SH, Ho BK, Dudek NL, Purcell AW. HLA class II immunopeptidomics reveals that co-inherited HLA-allotypes within an extended haplotype can improve proteome coverage for immunosurveillance. Proteomics 2021; 21:e2000160. [PMID: 34357683 DOI: 10.1002/pmic.202000160] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 01/05/2023]
Abstract
Human leucocyte antigen (HLA) class II molecules in humans are encoded by three different loci, HLA-DR, -DQ, and -DP. These molecules share approximately 70% sequence similarity and all present peptide ligands to circulating T cells. While the peptide repertoires of numerous HLA-DR, -DQ, and -DP allotypes have been examined, there have been few reports on the combined repertoire of these co-inherited molecules expressed in a single cell as an extended HLA haplotype. Here we describe the endogenous peptide repertoire of a human B lymphoblastoid cell line (C1R) expressing the class II haplotype HLA-DR12/DQ7/DP4. We have identified 71350 unique naturally processed peptides presented collectively by HLA-DR12, HLA-DQ7, or HLA-DP4. The resulting "haplodome" is complemented by the cellular proteome defined by standard LC-MS/MS approaches. This large dataset has shed light on properties of these class II ligands especially the preference for membrane and extracellular source proteins. Our data also provides insights into the co-evolution of these conserved haplotypes of closely linked and co-inherited HLA molecules; which together increase sequence coverage of cellular proteins for immune surveillance with minimal overlap between each co-inherited HLA-class II allomorph.
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Affiliation(s)
- Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Bosco K Ho
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nadine L Dudek
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
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13
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Khoury G, Lee MY, Ramarathinam SH, McMahon J, Purcell AW, Sonza S, Lewin SR, Purcell DFJ. The RNA-Binding Proteins SRP14 and HMGB3 Control HIV-1 Tat mRNA Processing and Translation During HIV-1 Latency. Front Genet 2021; 12:680725. [PMID: 34194479 PMCID: PMC8236859 DOI: 10.3389/fgene.2021.680725] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/17/2021] [Indexed: 01/23/2023] Open
Abstract
HIV-1 Tat protein is essential for virus production. RNA-binding proteins that facilitate Tat production may be absent or downregulated in resting CD4+ T-cells, the main reservoir of latent HIV in people with HIV (PWH) on antiretroviral therapy (ART). In this study, we examined the role of Tat RNA-binding proteins on the expression of Tat and control of latent and productive infection. Affinity purification coupled with mass spectrometry analysis was used to detect binding partners of MS2-tagged tat mRNA in a T cell-line model of HIV latency. The effect of knockdown and overexpression of the proteins of interest on Tat transactivation and translation was assessed by luciferase-based reporter assays and infections with a dual color HIV reporter virus. Out of the 243 interactions identified, knockdown of SRP14 (Signal Recognition Particle 14) negatively affected tat mRNA processing and translation as well as Tat-mediated transactivation, which led to an increase in latent infection. On the other hand, knockdown of HMGB3 (High Mobility Group Box 3) resulted in an increase in Tat transactivation and translation as well as an increase in productive infection. Footprinting experiments revealed that SRP14 and HMGB3 proteins bind to TIM-TAM, a conserved RNA sequence-structure in tat mRNA that functions as a Tat IRES modulator of tat mRNA. Overexpression of SRP14 in resting CD4+ T-cells from patients on ART was sufficient to reverse HIV-1 latency and induce virus production. The role of SRP14 and HMGB3 proteins in controlling HIV Tat expression during latency will be further assessed as potential drug targets.
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Affiliation(s)
- Georges Khoury
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Michelle Y. Lee
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Sri H. Ramarathinam
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - James McMahon
- Victorian Infectious Diseases Service, The Royal Melbourne Hospital at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Anthony W. Purcell
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Secondo Sonza
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - Sharon R. Lewin
- Victorian Infectious Diseases Service, The Royal Melbourne Hospital at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, VIC, Australia
| | - Damian F. J. Purcell
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
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14
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Li C, Revote J, Ramarathinam SH, Chung SZ, Croft NP, Scull KE, Huang Z, Ayala R, Braun A, Mifsud NA, Illing PT, Faridi P, Purcell AW. Resourcing, annotating, and analysing synthetic peptides of SARS-CoV-2 for immunopeptidomics and other immunological studies. Proteomics 2021; 21:e2100036. [PMID: 33811468 PMCID: PMC8250278 DOI: 10.1002/pmic.202100036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/15/2021] [Accepted: 03/15/2021] [Indexed: 12/27/2022]
Abstract
SARS‐CoV‐2 has caused a significant ongoing pandemic worldwide. A number of studies have examined the T cell mediated immune responses against SARS‐CoV‐2, identifying potential T cell epitopes derived from the SARS‐CoV‐2 proteome. Such studies will aid in identifying targets for vaccination and immune monitoring. In this study, we applied tandem mass spectrometry and proteomic techniques to a library of ∼40,000 synthetic peptides, in order to generate a large dataset of SARS‐CoV‐2 derived peptide MS/MS spectra. On this basis, we built an online knowledgebase, termed virusMS (https://virusms.erc.monash.edu/), to document, annotate and analyse these synthetic peptides and their spectral information. VirusMS incorporates a user‐friendly interface to facilitate searching, browsing and downloading the database content. Detailed annotations of the peptides, including experimental information, peptide modifications, predicted peptide‐HLA (human leukocyte antigen) binding affinities, and peptide MS/MS spectral data, are provided in virusMS.
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Affiliation(s)
- Chen Li
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Jerico Revote
- Monash Bioinformatics Platform, Monash University, Melbourne, Victoria, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Shan Zou Chung
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nathan P Croft
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Katherine E Scull
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Ziyi Huang
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Rochelle Ayala
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Asolina Braun
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nicole A Mifsud
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Patricia T Illing
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Pouya Faridi
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
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15
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Abstract
This article describes the purification of HLA-bound peptides and their subsequent sequencing by mass spectrometry. These methods can be used for both HLA class I and class II molecules and can be adapted to different species depending on the availability of specific antibodies. Peptides can be successfully isolated from a variety of sample types, including in vitro cultured cells and primary tissues. The method involves the affinity capture of HLA-peptide complexes and separation of peptides from HLA heavy chains, followed by tailored interrogation by mass spectrometry to take into account the non-tryptic nature of endogenously derived HLA-bound peptides. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Preparation of immunoaffinity column Alternate Protocol 1: Preparation of microscale immunoaffinity column Basic Protocol 2: Generation of cell lysate and HLA immunoaffinity purification Alternate Protocol 2: Microscale immunoaffinity purification Basic Protocol 3: Separation of HLA peptides by reverse-phase high-performance liquid chromatography (RP-HPLC) Alternate Protocol 3: Isolation of HLA peptides using molecular weight cutoff (MWCO) filter Basic Protocol 4: Mass spectrometry and data analysis.
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Affiliation(s)
- Kirti Pandey
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
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16
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Gastaldello A, Ramarathinam SH, Bailey A, Owen R, Turner S, Kontouli N, Elliott T, Skipp P, Purcell AW, Siddle HV. The immunopeptidomes of two transmissible cancers and their host have a common, dominant peptide motif. Immunology 2021; 163:169-184. [PMID: 33460454 PMCID: PMC8114214 DOI: 10.1111/imm.13307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/16/2020] [Accepted: 01/04/2021] [Indexed: 12/28/2022] Open
Abstract
Transmissible cancers are malignant cells that can spread between individuals of a population, akin to both a parasite and a mobile graft. The survival of the Tasmanian devil, the largest remaining marsupial carnivore, is threatened by the remarkable emergence of two independent lineages of transmissible cancer, devil facial tumour (DFT) 1 and devil facial tumour 2 (DFT2). To aid the development of a vaccine and to interrogate how histocompatibility barriers can be overcome, we analysed the peptides bound to major histocompatibility complex class I (MHC‐I) molecules from Tasmanian devil cells and representative cell lines of each transmissible cancer. Here, we show that DFT1 + IFN‐γ and DFT2 cell lines express a restricted repertoire of MHC‐I allotypes compared with fibroblast cells, potentially reducing the breadth of peptide presentation. Comparison of the peptidomes from DFT1 + IFNγ, DFT2 and host fibroblast cells demonstrates a dominant motif, despite differences in MHC‐I allotypes between the cell lines, with preference for a hydrophobic leucine residue at position 3 and position Ω of peptides. DFT1 and DFT2 both present peptides derived from neural proteins, which reflects a shared cellular origin that could be exploited for vaccine design. These results suggest that polymorphisms in MHC‐I molecules between tumours and host can be ‘hidden’ by a common peptide motif, providing the potential for permissive passage of infectious cells and demonstrating complexity in mammalian histocompatibility barriers.
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Affiliation(s)
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and the Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Alistair Bailey
- Centre for Cancer Immunology, University of Southampton, Southampton, UK.,Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Rachel Owen
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Steven Turner
- Centre for Cancer Immunology, University of Southampton, Southampton, UK
| | - N Kontouli
- Centre for Cancer Immunology, University of Southampton, Southampton, UK
| | - Tim Elliott
- Centre for Cancer Immunology, University of Southampton, Southampton, UK.,Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Paul Skipp
- School of Biological Sciences, University of Southampton, Southampton, UK.,Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and the Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Hannah V Siddle
- School of Biological Sciences, University of Southampton, Southampton, UK.,Institute for Life Sciences, University of Southampton, Southampton, UK
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17
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Jappe EC, Garde C, Ramarathinam SH, Passantino E, Illing PT, Mifsud NA, Trolle T, Kringelum JV, Croft NP, Purcell AW. Thermostability profiling of MHC-bound peptides: a new dimension in immunopeptidomics and aid for immunotherapy design. Nat Commun 2020; 11:6305. [PMID: 33298915 PMCID: PMC7726561 DOI: 10.1038/s41467-020-20166-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 11/18/2020] [Indexed: 12/12/2022] Open
Abstract
The features of peptide antigens that contribute to their immunogenicity are not well understood. Although the stability of peptide-MHC (pMHC) is known to be important, current assays assess this interaction only for peptides in isolation and not in the context of natural antigen processing and presentation. Here, we present a method that provides a comprehensive and unbiased measure of pMHC stability for thousands of individual ligands detected simultaneously by mass spectrometry (MS). The method allows rapid assessment of intra-allelic and inter-allelic differences in pMHC stability and reveals profiles of stability that are broader than previously appreciated. The additional dimensionality of the data facilitated the training of a model which improves the prediction of peptide immunogenicity, specifically of cancer neoepitopes. This assay can be applied to any cells bearing MHC or MHC-like molecules, offering insight into not only the endogenous immunopeptidome, but also that of neoepitopes and pathogen-derived sequences.
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Affiliation(s)
- Emma C Jappe
- Evaxion Biotech, Bredgade 34E, 1260, Copenhagen, Denmark
- Department of Health Technology, Technical University of Denmark, 2800, Lyngby, Denmark
| | | | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Ethan Passantino
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Patricia T Illing
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Nicole A Mifsud
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Thomas Trolle
- Evaxion Biotech, Bredgade 34E, 1260, Copenhagen, Denmark
| | | | - Nathan P Croft
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
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18
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Faridi P, Woods K, Ostrouska S, Deceneux C, Aranha R, Duscharla D, Wong SQ, Chen W, Ramarathinam SH, Lim Kam Sian TCC, Croft NP, Li C, Ayala R, Cebon JS, Purcell AW, Schittenhelm RB, Behren A. Spliced Peptides and Cytokine-Driven Changes in the Immunopeptidome of Melanoma. Cancer Immunol Res 2020; 8:1322-1334. [PMID: 32938616 DOI: 10.1158/2326-6066.cir-19-0894] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/20/2020] [Accepted: 08/20/2020] [Indexed: 11/16/2022]
Abstract
Antigen recognition by CD8+ T cells is governed by the pool of peptide antigens presented on the cell surface in the context of HLA class I complexes. Studies have shown not only a high degree of plasticity in the immunopeptidome, but also that a considerable fraction of all presented peptides is generated through proteasome-mediated splicing of noncontiguous regions of proteins to form novel peptide antigens. Here, we used high-resolution mass spectrometry combined with new bioinformatic approaches to characterize the immunopeptidome of melanoma cells in the presence or absence of IFNγ. In total, we identified more than 60,000 peptides from a single patient-derived cell line (LM-MEL-44) and demonstrated that IFNγ induced changes in the peptidome, with an overlap of only approximately 50% between basal and treated cells. Around 6% to 8% of the peptides were identified as cis-spliced peptides, and 2,213 peptides (1,827 linear and 386 cis-spliced peptides) were derived from known melanoma-associated antigens. These peptide antigens were equally distributed between the constitutive- and IFNγ-induced peptidome. We next examined additional HLA-matched patient-derived cell lines to investigate how frequently these peptides were identified and found that a high proportion of both linear and spliced peptides was conserved between individual patient tumors, drawing on data amassing to more than 100,000 peptide sequences. Several of these peptides showed in vitro immunogenicity across multiple patients with melanoma. These observations highlight the breadth and complexity of the repertoire of immunogenic peptides that can be exploited therapeutically and suggest that spliced peptides are a major class of tumor antigens.
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Affiliation(s)
- Pouya Faridi
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Katherine Woods
- Cancer Immunobiology, Olivia Newton-John Cancer Research Institute, Austin Hospital, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
| | - Simone Ostrouska
- Cancer Immunobiology, Olivia Newton-John Cancer Research Institute, Austin Hospital, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
| | - Cyril Deceneux
- Cancer Immunobiology, Olivia Newton-John Cancer Research Institute, Austin Hospital, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
| | - Ritchlynn Aranha
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Divya Duscharla
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Stephen Q Wong
- Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Weisan Chen
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Terry C C Lim Kam Sian
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nathan P Croft
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Chen Li
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Rochelle Ayala
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Jonathan S Cebon
- Cancer Immunobiology, Olivia Newton-John Cancer Research Institute, Austin Hospital, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
| | - Ralf B Schittenhelm
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia. .,Monash Proteomics & Metabolomics Facility, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Andreas Behren
- Cancer Immunobiology, Olivia Newton-John Cancer Research Institute, Austin Hospital, Heidelberg, Victoria, Australia. .,School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
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19
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Mei S, Ayala R, Ramarathinam SH, Illing PT, Faridi P, Song J, Purcell AW, Croft NP. Immunopeptidomic Analysis Reveals That Deamidated HLA-bound Peptides Arise Predominantly from Deglycosylated Precursors. Mol Cell Proteomics 2020; 19:1236-1247. [PMID: 32357974 PMCID: PMC7338083 DOI: 10.1074/mcp.ra119.001846] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 04/20/2020] [Indexed: 12/20/2022] Open
Abstract
The presentation of post-translationally modified (PTM) peptides by cell surface HLA molecules has the potential to increase the diversity of targets for surveilling T cells. Although immunopeptidomics studies routinely identify thousands of HLA-bound peptides from cell lines and tissue samples, in-depth analyses of the proportion and nature of peptides bearing one or more PTMs remains challenging. Here we have analyzed HLA-bound peptides from a variety of allotypes and assessed the distribution of mass spectrometry-detected PTMs, finding deamidation of asparagine or glutamine to be highly prevalent. Given that asparagine deamidation may arise either spontaneously or through enzymatic reaction, we assessed allele-specific and global motifs flanking the modified residues. Notably, we found that the N-linked glycosylation motif NX(S/T) was highly abundant across asparagine-deamidated HLA-bound peptides. This finding, demonstrated previously for a handful of deamidated T cell epitopes, implicates a more global role for the retrograde transport of nascently N-glycosylated polypeptides from the ER and their subsequent degradation within the cytosol to form HLA-ligand precursors. Chemical inhibition of Peptide:N-Glycanase (PNGase), the endoglycosidase responsible for the removal of glycans from misfolded and retrotranslocated glycoproteins, greatly reduced presentation of this subset of deamidated HLA-bound peptides. Importantly, there was no impact of PNGase inhibition on peptides not containing a consensus NX(S/T) motif. This indicates that a large proportion of HLA-I bound asparagine deamidated peptides are generated from formerly glycosylated proteins that have undergone deglycosylation via the ER-associated protein degradation (ERAD) pathway. The information herein will help train deamidation prediction models for HLA-peptide repertoires and aid in the design of novel T cell therapeutic targets derived from glycoprotein antigens.
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Affiliation(s)
- Shutao Mei
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Rochelle Ayala
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Sri H Ramarathinam
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Patricia T Illing
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Pouya Faridi
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Jiangning Song
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia
| | - Anthony W Purcell
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia.
| | - Nathan P Croft
- Biomedicine Discovery Institute and Department of Biochemistry & Molecular Biology, Monash University, Melbourne, VIC, Australia.
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20
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Osterbye T, Nielsen M, Dudek NL, Ramarathinam SH, Purcell AW, Schafer-Nielsen C, Buus S. HLA Class II Specificity Assessed by High-Density Peptide Microarray Interactions. J Immunol 2020; 205:290-299. [PMID: 32482711 DOI: 10.4049/jimmunol.2000224] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 04/22/2020] [Indexed: 01/26/2023]
Abstract
The ability to predict and/or identify MHC binding peptides is an essential component of T cell epitope discovery, something that ultimately should benefit the development of vaccines and immunotherapies. In particular, MHC class I prediction tools have matured to a point where accurate selection of optimal peptide epitopes is possible for virtually all MHC class I allotypes; in comparison, current MHC class II (MHC-II) predictors are less mature. Because MHC-II restricted CD4+ T cells control and orchestrated most immune responses, this shortcoming severely hampers the development of effective immunotherapies. The ability to generate large panels of peptides and subsequently large bodies of peptide-MHC-II interaction data are key to the solution of this problem, a solution that also will support the improvement of bioinformatics predictors, which critically relies on the availability of large amounts of accurate, diverse, and representative data. In this study, we have used rHLA-DRB1*01:01 and HLA-DRB1*03:01 molecules to interrogate high-density peptide arrays, in casu containing 70,000 random peptides in triplicates. We demonstrate that the binding data acquired contains systematic and interpretable information reflecting the specificity of the HLA-DR molecules investigated, suitable of training predictors able to predict T cell epitopes and peptides eluted from human EBV-transformed B cells. Collectively, with a cost per peptide reduced to a few cents, combined with the flexibility of rHLA technology, this poses an attractive strategy to generate vast bodies of MHC-II binding data at an unprecedented speed and for the benefit of generating peptide-MHC-II binding data as well as improving MHC-II prediction tools.
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Affiliation(s)
- Thomas Osterbye
- Department of Immunology and Microbiology, University of Copenhagen, DK-2200 Copenhagen, Denmark;
| | - Morten Nielsen
- Department of Health Technology, Technical University of Denmark, DK-2800 Lyngby, Denmark.,Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín, B1650 San Martín, Argentina
| | - Nadine L Dudek
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and
| | - Sri H Ramarathinam
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and
| | - Anthony W Purcell
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and
| | | | - Soren Buus
- Department of Immunology and Microbiology, University of Copenhagen, DK-2200 Copenhagen, Denmark
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21
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Le Nours J, Gherardin NA, Ramarathinam SH, Awad W, Wiede F, Gully BS, Khandokar Y, Praveena T, Wubben JM, Sandow JJ, Webb AI, von Borstel A, Rice MT, Redmond SJ, Seneviratna R, Sandoval-Romero ML, Li S, Souter MNT, Eckle SBG, Corbett AJ, Reid HH, Liu L, Fairlie DP, Giles EM, Westall GP, Tothill RW, Davey MS, Berry R, Tiganis T, McCluskey J, Pellicci DG, Purcell AW, Uldrich AP, Godfrey DI, Rossjohn J. A class of γδ T cell receptors recognize the underside of the antigen-presenting molecule MR1. Science 2020; 366:1522-1527. [PMID: 31857486 DOI: 10.1126/science.aav3900] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 09/20/2019] [Accepted: 11/21/2019] [Indexed: 12/12/2022]
Abstract
T cell receptors (TCRs) recognize antigens presented by major histocompatibility complex (MHC) and MHC class I-like molecules. We describe a diverse population of human γδ T cells isolated from peripheral blood and tissues that exhibit autoreactivity to the monomorphic MHC-related protein 1 (MR1). The crystal structure of a γδTCR-MR1-antigen complex starkly contrasts with all other TCR-MHC and TCR-MHC-I-like complex structures. Namely, the γδTCR binds underneath the MR1 antigen-binding cleft, where contacts are dominated by the MR1 α3 domain. A similar pattern of reactivity was observed for diverse MR1-restricted γδTCRs from multiple individuals. Accordingly, we simultaneously report MR1 as a ligand for human γδ T cells and redefine the parameters for TCR recognition.
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Affiliation(s)
- Jérôme Le Nours
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Nicholas A Gherardin
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Sri H Ramarathinam
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Wael Awad
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Florian Wiede
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Peter MacCallum Cancer Centre, Melbourne, Victoria 3000, Australia
| | - Benjamin S Gully
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Yogesh Khandokar
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - T Praveena
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Jacinta M Wubben
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Jarrod J Sandow
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Andrew I Webb
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.,Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Anouk von Borstel
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Michael T Rice
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Samuel J Redmond
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Rebecca Seneviratna
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Maria L Sandoval-Romero
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Shihan Li
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Michael N T Souter
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Sidonia B G Eckle
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Alexandra J Corbett
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Hugh H Reid
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Ligong Liu
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Queensland, Brisbane, Queensland 4072, Australia
| | - David P Fairlie
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Edward M Giles
- Department of Paediatrics, Monash University, and Centre for Innate Immunity and Infectious Disease, Hudson Institute of Medicine, Clayton, Victoria 3168, Australia
| | - Glen P Westall
- Lung Transplant Service, Alfred Hospital, Melbourne, Victoria 3004, Australia.,Department of Medicine, Monash University, Clayton, Victoria 3800, Australia
| | - Richard W Tothill
- Department of Clinical Pathology and Centre for Cancer Research, University of Melbourne, Parkville, Victoria 3052, Australia.,The Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3000, Australia
| | - Martin S Davey
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Richard Berry
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Tony Tiganis
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Peter MacCallum Cancer Centre, Melbourne, Victoria 3000, Australia
| | - James McCluskey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Daniel G Pellicci
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Adam P Uldrich
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Dale I Godfrey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000, Australia. .,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia. .,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.,Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
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22
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Faridi P, Li C, Ramarathinam SH, Illing PT, Mifsud NA, Ayala R, Song J, Gearing LJ, Croft NP, Purcell AW. Response to Comment on "A subset of HLA-I peptides are not genomically templated: Evidence for cis- and trans-spliced peptide ligands". Sci Immunol 2020; 4:4/38/eaaw8457. [PMID: 31420321 DOI: 10.1126/sciimmunol.aaw8457] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 07/15/2019] [Indexed: 12/15/2022]
Abstract
This is our response to the Technical Comment by Rolfs et al. where we point out errors in their reanalysis of our data.
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Affiliation(s)
- Pouya Faridi
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Chen Li
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Department of Biology, Institute of Molecular Systems Biology, ETH-Zürich, Zürich 8093, Switzerland
| | - Sri H Ramarathinam
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Patricia T Illing
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Nicole A Mifsud
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Rochelle Ayala
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Jiangning Song
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Centre for Data Science, Faculty of Information Technology, Monash University, Melbourne, Victoria 3800, Australia
| | - Linden J Gearing
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research and Department of Molecular and Translational Science, School of Clinical Science, Monash University, Clayton, Victoria 3168, Australia
| | - Nathan P Croft
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
| | - Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
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23
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Faridi P, Li C, Ramarathinam SH, Vivian JP, Illing PT, Mifsud NA, Ayala R, Song J, Gearing LJ, Hertzog PJ, Ternette N, Rossjohn J, Croft NP, Purcell AW. A subset of HLA-I peptides are not genomically templated: Evidence for cis- and trans-spliced peptide ligands. Sci Immunol 2019; 3:3/28/eaar3947. [PMID: 30315122 DOI: 10.1126/sciimmunol.aar3947] [Citation(s) in RCA: 114] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 05/29/2018] [Accepted: 08/31/2018] [Indexed: 12/19/2022]
Abstract
The diversity of peptides displayed by class I human leukocyte antigen (HLA) plays an essential role in T cell immunity. The peptide repertoire is extended by various posttranslational modifications, including proteasomal splicing of peptide fragments from distinct regions of an antigen to form nongenomically templated cis-spliced sequences. Previously, it has been suggested that a fraction of the immunopeptidome constitutes such cis-spliced peptides; however, because of computational limitations, it has not been possible to assess whether trans-spliced peptides (i.e., the fusion of peptide segments from distinct antigens) are also bound and presented by HLA molecules, and if so, in what proportion. Here, we have developed and applied a bioinformatic workflow and demonstrated that trans-spliced peptides are presented by HLA-I, and their abundance challenges current models of proteasomal splicing that predict cis-splicing as the most probable outcome. These trans-spliced peptides display canonical HLA-binding sequence features and are as frequently identified as cis-spliced peptides found bound to a number of different HLA-A and HLA-B allotypes. Structural analysis reveals that the junction between spliced peptides is highly solvent exposed and likely to participate in T cell receptor interactions. These results highlight the unanticipated diversity of the immunopeptidome and have important implications for autoimmunity, vaccine design, and immunotherapy.
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Affiliation(s)
- Pouya Faridi
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Chen Li
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Department of Biology, Institute of Molecular Systems Biology,ETH Zurich, Zurich 8093, Switzerland
| | - Sri H Ramarathinam
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Julian P Vivian
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Patricia T Illing
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Nicole A Mifsud
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Rochelle Ayala
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Jiangning Song
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Monash Centre for Data Science, Faculty of Information Technology, Monash University, Melbourne, Victoria 3800, Australia
| | - Linden J Gearing
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research and Department of Molecular and Translational Science, School of Clinical Science, Monash University, Clayton, Victoria 3168, Australia
| | - Paul J Hertzog
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research and Department of Molecular and Translational Science, School of Clinical Science, Monash University, Clayton, Victoria 3168, Australia
| | | | - Jamie Rossjohn
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.,Institute of Infection and Immunity, Cardiff University School of Medicine,Heath Park, Cardiff CF14 4XN, UK
| | - Nathan P Croft
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
| | - Anthony W Purcell
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
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24
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Garde C, Ramarathinam SH, Jappe EC, Nielsen M, Kringelum JV, Trolle T, Purcell AW. Improved peptide-MHC class II interaction prediction through integration of eluted ligand and peptide affinity data. Immunogenetics 2019; 71:445-454. [PMID: 31183519 DOI: 10.1007/s00251-019-01122-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 05/31/2019] [Indexed: 01/17/2023]
Abstract
Major histocompatibility complex (MHC) class II antigen presentation is a key component in eliciting a CD4+ T cell response. Precise prediction of peptide-MHC (pMHC) interactions has thus become a cornerstone in defining epitope candidates for rational vaccine design. Current pMHC prediction tools have, so far, primarily focused on inference from in vitro binding affinity. In the current study, we collate a large set of MHC class II eluted ligands generated by mass spectrometry to guide the prediction of MHC class II antigen presentation. We demonstrate that models developed on eluted ligands outperform those developed on pMHC binding affinity data. The predictive performance can be further enhanced by combining the eluted ligand and pMHC affinity data in a single prediction model. Furthermore, by including ligand data, the peptide length preference of MHC class II can be accurately learned by the prediction model. Finally, we demonstrate that our model significantly outperforms the current state-of-the-art prediction method, NetMHCIIpan, on an external dataset of eluted ligands and appears superior in identifying CD4+ T cell epitopes.
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Affiliation(s)
- Christian Garde
- Evaxion Biotech, Bredgade 34E, DK-1260, Copenhagen, Denmark.
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology & Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia
| | - Emma C Jappe
- Evaxion Biotech, Bredgade 34E, DK-1260, Copenhagen, Denmark.,Department of Bio and Health Informatics, Technical University of Denmark, DK-2800, Lyngby, Denmark
| | - Morten Nielsen
- Department of Bio and Health Informatics, Technical University of Denmark, DK-2800, Lyngby, Denmark.,Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín, Buenos Aires, Argentina
| | | | - Thomas Trolle
- Evaxion Biotech, Bredgade 34E, DK-1260, Copenhagen, Denmark
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology & Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia.
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25
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Purcell AW, Ramarathinam SH, Ternette N. Mass spectrometry-based identification of MHC-bound peptides for immunopeptidomics. Nat Protoc 2019; 14:1687-1707. [PMID: 31092913 DOI: 10.1038/s41596-019-0133-y] [Citation(s) in RCA: 180] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 01/08/2019] [Indexed: 01/13/2023]
Abstract
Peptide antigens bound to molecules encoded by the major histocompatibility complex (MHC) and presented on the cell surface form the targets of T lymphocytes. This critical arm of the adaptive immune system facilitates the eradication of pathogen-infected and cancerous cells, as well as the production of antibodies. Methods to identify these peptide antigens are critical to the development of new vaccines, for which the goal is the generation of effective adaptive immune responses and long-lasting immune memory. Here, we describe a robust protocol for the identification of MHC-bound peptides from cell lines and tissues, using nano-ultra-performance liquid chromatography coupled to high-resolution mass spectrometry (nUPLC-MS/MS) and recent improvements in methods for isolation and characterization of these peptides. The protocol starts with the immunoaffinity capture of naturally processed MHC-peptide complexes. The peptides dissociate from the class I human leukocyte antigens (HLAs) upon acid denaturation. This peptide cargo is then extracted and separated into fractions by HPLC, and the peptides in these fractions are identified using nUPLC-MS/MS. With this protocol, several thousand peptides can be identified from a wide variety of cell types, including cancerous and infected cells and those from tissues, with a turnaround time of 2-3 d.
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Affiliation(s)
- Anthony W Purcell
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Nicola Ternette
- The Jenner Institute, Mass Spectrometry Laboratory, Target Discovery Institute, University of Oxford, Oxford, UK.
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26
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Abstract
INTRODUCTION Our immune system discriminates self from non-self by examining the peptide cargo of human leukocyte antigen (HLA) molecules displayed on the cell surface. Successful recognition of HLA-bound non-self peptides can induce T cell responses leading to, for example, the destruction of infected cells. Today, largely due to advances in technology, we have an unprecedented capability to identify the nature of these presented peptides and unravel the true complexity of antigen presentation. Areas covered: In addition to conventional linear peptides, HLA molecules also present post-translationally modified sequences comprising a wealth of chemical and structural modifications, including a novel class of noncontiguous spliced peptides. This review focuses on these emerging themes in antigen presentation and how mass spectrometry in particular has contributed to a new view of the antigenic landscape that is presented to the immune system. Expert Commentary: Advances in the sensitivity of mass spectrometers and use of hybrid fragmentation technologies will provide more information-rich spectra of HLA bound peptides leading to more definitive identification of T cell epitopes. Coupled with improvements in sample preparation and new informatics workflows, studies will access novel classes of peptide antigen and allow interrogation of rare and clinically relevant samples.
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Affiliation(s)
- Sri H Ramarathinam
- a Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute , Monash University , Clayton , VIC , Australia
| | - Nathan P Croft
- a Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute , Monash University , Clayton , VIC , Australia
| | - Patricia T Illing
- a Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute , Monash University , Clayton , VIC , Australia
| | - Pouya Faridi
- a Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute , Monash University , Clayton , VIC , Australia
| | - Anthony W Purcell
- a Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute , Monash University , Clayton , VIC , Australia
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27
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Ramarathinam SH, Gras S, Alcantara S, Yeung AWS, Mifsud NA, Sonza S, Illing PT, Glaros EN, Center RJ, Thomas SR, Kent SJ, Ternette N, Purcell DFJ, Rossjohn J, Purcell AW. Identification of Native and Posttranslationally Modified HLA-B*57:01-Restricted HIV Envelope Derived Epitopes Using Immunoproteomics. Proteomics 2018; 18:e1700253. [PMID: 29437277 DOI: 10.1002/pmic.201700253] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/29/2018] [Indexed: 12/20/2022]
Abstract
The recognition of pathogen-derived peptides by T lymphocytes is the cornerstone of adaptive immunity, whereby intracellular antigens are degraded in the cytosol and short peptides assemble with class I human leukocyte antigen (HLA) molecules in the ER. These peptide-HLA complexes egress to the cell surface and are scrutinized by cytotoxic CD8+ T-cells leading to the eradication of the infected cell. Here, naturally presented HLA-B*57:01 bound peptides derived from the envelope protein of the human immunodeficiency virus (HIVenv) are identified. HIVenv peptides are present at a very small percentage of the overall HLA-B*57:01 peptidome (<0.1%) and both native and posttranslationally modified forms of two distinct HIV peptides are identified. Notably, a peptide bearing a natively encoded C-terminal tryptophan residue is also present in a modified form containing a kynurenine residue. Kynurenine is a major product of tryptophan catabolism and is abundant during inflammation and infection. Binding of these peptides at a molecular level and their immunogenicity in preliminary functional studies are examined. Modest immune responses are observed to the modified HIVenv peptide, highlighting a potential role for kynurenine-modified peptides in the immune response to HIV and other viral infections.
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Affiliation(s)
- Sri H Ramarathinam
- Infection and Immunity Program, Biomedicine Discovery Institute & Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Stephanie Gras
- Infection and Immunity Program, Biomedicine Discovery Institute & Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia.,ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia
| | - Sheilajen Alcantara
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Australia
| | - Amanda W S Yeung
- Mechanisms of Disease and Translational Medicine, Department of Pathology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Nicole A Mifsud
- Infection and Immunity Program, Biomedicine Discovery Institute & Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Secondo Sonza
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Australia
| | - Patricia T Illing
- Infection and Immunity Program, Biomedicine Discovery Institute & Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Elias N Glaros
- Mechanisms of Disease and Translational Medicine, Department of Pathology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Robert J Center
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Australia.,Burnet Institute, Melbourne, Australia
| | - Shane R Thomas
- Mechanisms of Disease and Translational Medicine, Department of Pathology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, Australia
| | - Stephen J Kent
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Australia.,Melbourne Sexual Health Centre, Central Clinical School, Monash University, Melbourne, Australia.,ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, University of Melbourne, Parkville, Australia
| | - Nicola Ternette
- The Jenner Institute, Target Discovery Institute Mass Spectrometry Laboratory, University of Oxford, Oxford, UK
| | - Damian F J Purcell
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program, Biomedicine Discovery Institute & Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia.,ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia.,Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Anthony W Purcell
- Infection and Immunity Program, Biomedicine Discovery Institute & Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
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28
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Ting YT, Petersen J, Ramarathinam SH, Scally SW, Loh KL, Thomas R, Suri A, Baker DG, Purcell AW, Reid HH, Rossjohn J. The interplay between citrullination and HLA-DRB1 polymorphism in shaping peptide binding hierarchies in rheumatoid arthritis. J Biol Chem 2018; 293:3236-3251. [PMID: 29317506 DOI: 10.1074/jbc.ra117.001013] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 12/21/2017] [Indexed: 12/22/2022] Open
Abstract
The HLA-DRB1 locus is strongly associated with rheumatoid arthritis (RA) susceptibility, whereupon citrullinated self-peptides bind to HLA-DR molecules bearing the shared epitope (SE) amino acid motif. However, the differing propensity for citrullinated/non-citrullinated self-peptides to bind given HLA-DR allomorphs remains unclear. Here, we used a fluorescence polarization assay to determine a hierarchy of binding affinities of 34 self-peptides implicated in RA against three HLA-DRB1 allomorphs (HLA-DRB1*04:01/*04:04/*04:05) each possessing the SE motif. For all three HLA-DRB1 allomorphs, we observed a strong correlation between binding affinity and citrullination at P4 of the bound peptide ligand. A differing hierarchy of peptide-binding affinities across the three HLA-DRB1 allomorphs was attributable to the β-chain polymorphisms that resided outside the SE motif and were consistent with sequences of naturally presented peptide ligands. Structural determination of eight HLA-DR4-self-epitope complexes revealed strict conformational convergence of the P4-Cit and surrounding HLA β-chain residues. Polymorphic residues that form part of the P1 and P9 pockets of the HLA-DR molecules provided a structural basis for the preferential binding of the citrullinated self-peptides to the HLA-DR4 allomorphs. Collectively, we provide a molecular basis for the interplay between citrullination of self-antigens and HLA polymorphisms that shape peptide-HLA-DR4 binding affinities in RA.
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Affiliation(s)
- Yi Tian Ting
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and
| | - Jan Petersen
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and.,the Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Sri H Ramarathinam
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and
| | - Stephen W Scally
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and
| | - Khai L Loh
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and
| | - Ranjeny Thomas
- the University of Queensland Diamantina Institute, Translational Research Institute, Princess Alexandra Hospital, Brisbane 4102, Australia
| | - Anish Suri
- the Janssen Research and Development, Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, B-2340-Beerse, Belgium
| | - Daniel G Baker
- the Janssen Research and Development, LLC, Spring House, Pennsylvania 19002, and
| | - Anthony W Purcell
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and
| | - Hugh H Reid
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and .,the Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Jamie Rossjohn
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, and .,the Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.,the Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, Wales, United Kingdom
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29
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Caron E, Espona L, Kowalewski DJ, Schuster H, Ternette N, Alpízar A, Schittenhelm RB, Ramarathinam SH, Lindestam Arlehamn CS, Chiek Koh C, Gillet LC, Rabsteyn A, Navarro P, Kim S, Lam H, Sturm T, Marcilla M, Sette A, Campbell DS, Deutsch EW, Moritz RL, Purcell AW, Rammensee HG, Stevanovic S, Aebersold R. An open-source computational and data resource to analyze digital maps of immunopeptidomes. eLife 2015; 4. [PMID: 26154972 PMCID: PMC4507788 DOI: 10.7554/elife.07661] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 07/07/2015] [Indexed: 02/06/2023] Open
Abstract
We present a novel mass spectrometry-based high-throughput workflow and an open-source computational and data resource to reproducibly identify and quantify HLA-associated peptides. Collectively, the resources support the generation of HLA allele-specific peptide assay libraries consisting of consensus fragment ion spectra, and the analysis of quantitative digital maps of HLA peptidomes generated from a range of biological sources by SWATH mass spectrometry (MS). This study represents the first community-based effort to develop a robust platform for the reproducible and quantitative measurement of the entire repertoire of peptides presented by HLA molecules, an essential step towards the design of efficient immunotherapies. DOI:http://dx.doi.org/10.7554/eLife.07661.001 The cells of the immune system protect us by recognizing telltale molecules produced by damaged and diseased cells, or by infection-causing microorganisms (which are also called pathogens). To help with this process, the cells in our bodies display small fragments of proteins (called peptides) on their surface that are then checked by the immune cells. Collectively, these peptides are referred to as the ‘immunopeptidome’, and deciphering the complexity of the human immunopeptidome is important for both basic research and medical science. Such an achievement would help to guide the development of next-generation vaccines and therapies against autoimmune disorders, infectious diseases and cancers. In the past, immune peptides were mostly identified using a technique that is commonly called ‘shotgun’ mass spectrometry. However, this approach doesn't always provide reproducible results. In 2012, researchers reported the development of a new approach—which they called ‘SWATH’ mass spectrometry—that could yield more reproducible data. Now, Caron et al.—including many of the researchers involved in the 2012 study—have developed a large collection of standardized tests that use SWATH mass spectrometry to analyze the human immunopeptidome. The workflow and the computational and data resources developed as part of this international effort are the first steps toward highly reproducible and measurable analyses of the immunopeptidome across many samples. Moreover, the large repository of assays generated by the project has been made public and will serve a large community of researchers, which should enable better collaborations. In the future, SWATH mass spectrometry could be used as a robust technology for the reproducible detection and measurement of pathogen-specific or cancer-specific immune peptides. This could greatly help in the design of personalized immune-based therapies. DOI:http://dx.doi.org/10.7554/eLife.07661.002
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Affiliation(s)
- Etienne Caron
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zurich, Switzerland
| | - Lucia Espona
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zurich, Switzerland
| | - Daniel J Kowalewski
- Department of Immunology, Interfaculty Institute for Cell Biology, University of Tübingen, Tübingen, Germany
| | - Heiko Schuster
- Department of Immunology, Interfaculty Institute for Cell Biology, University of Tübingen, Tübingen, Germany
| | - Nicola Ternette
- Target Discovery Institute Mass Spectrometry Laboratory, University of Oxford, Oxford, United Kingdom
| | - Adán Alpízar
- Proteomics Unit, Spanish National Biotechnology Centre, Madrid, Spain
| | - Ralf B Schittenhelm
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Sri H Ramarathinam
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | | | - Ching Chiek Koh
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zurich, Switzerland
| | - Ludovic C Gillet
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zurich, Switzerland
| | - Armin Rabsteyn
- Department of Immunology, Interfaculty Institute for Cell Biology, University of Tübingen, Tübingen, Germany
| | - Pedro Navarro
- Institute for Immunology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sangtae Kim
- Pacific Northwest National Laboratory, Richland, United States
| | - Henry Lam
- Division of Biomedical Engineering and Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Theo Sturm
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zurich, Switzerland
| | - Miguel Marcilla
- Proteomics Unit, Spanish National Biotechnology Centre, Madrid, Spain
| | - Alessandro Sette
- La Jolla Institute for Allergy and Immunology, La Jolla, United States
| | | | | | | | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Hans-Georg Rammensee
- Department of Immunology, Interfaculty Institute for Cell Biology, University of Tübingen, Tübingen, Germany
| | - Stefan Stevanovic
- Department of Immunology, Interfaculty Institute for Cell Biology, University of Tübingen, Tübingen, Germany
| | - Ruedi Aebersold
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zurich, Switzerland
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30
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Schittenhelm RB, Dudek NL, Croft NP, Ramarathinam SH, Purcell AW. A comprehensive analysis of constitutive naturally processed and presented HLA-C*04:01 (Cw4)-specific peptides. ACTA ACUST UNITED AC 2014; 83:174-9. [PMID: 24397554 DOI: 10.1111/tan.12282] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 11/06/2013] [Accepted: 12/03/2013] [Indexed: 02/01/2023]
Abstract
The human B lymphoblastoid cell line C1R is widely regarded as human leukocyte antigen-A (HLA-A)/HLA-B negative and is therefore frequently exploited as a recipient cell line to study HLA class I functions. However, the normal levels of HLA-C*04:01 often hamper the investigation of introduced HLA class I allomorphs, which is particularly evident in sensitive applications such as mass spectrometry. Here we describe the comprehensive analysis of endogenous HLA-C*04:01 ligands expressed on the surface of C1R cells to (i) define a large sequence dataset of HLA-C*04:01 ligands, to (ii) refine the HLA-C*04:01 peptide-binding motif and (iii) to provide a resource that allows discrimination between peptides bound to introduced HLA class I subtypes and to the endogenous HLA-C*04:01 molecules.
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Affiliation(s)
- R B Schittenhelm
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, 3800, Victoria, Australia
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31
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Scull KE, Dudek NL, Corbett AJ, Ramarathinam SH, Gorasia DG, Williamson NA, Purcell AW. Secreted HLA recapitulates the immunopeptidome and allows in-depth coverage of HLA A*02:01 ligands. Mol Immunol 2012; 51:136-42. [PMID: 22424782 DOI: 10.1016/j.molimm.2012.02.117] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 02/15/2012] [Accepted: 02/20/2012] [Indexed: 10/28/2022]
Abstract
HLA molecules are cell-surface glycoproteins that present peptides, derived from intracellular protein antigens, for surveillance by T lymphocytes. Secreted HLA (sHLA) technology is a powerful approach for studying these peptides, since it facilitates large-scale production of HLA-bound peptides. We compared secreted and membrane-bound forms of HLA A2 in terms of intracellular trafficking and their bound peptide repertoire (termed the immunopeptidome). We demonstrate that sHLA and membrane bound HLA (mHLA) negotiate intracellular compartments with similar maturation kinetics. Moreover, mass spectrometry revealed a substantial overlap in the immunopeptidome was observed when HLA A2-bound peptides were purified from various sources of sHLA and mHLA. By combining machine based algorithms with manual validation, we identified 1266 non-redundant peptides. Analysis of these peptides revealed a number bearing post-translational modifications, although some of these may arise spontaneously others represent modifications performed within the cell that survive antigen processing. Peptides bearing some of these modifications have not previously been described for HLA ligands, therefore, this compendium of 1266 non-redundant peptide sequences adds greatly to the existing database of HLA A2 ligands. Peptides from all sources displayed comparable HLA A2 consensus binding motifs, peptide lengths, predicted HLA A2 binding affinities and putative source antigens. We conclude that sHLA is a valid and useful technique for studying the immunopeptidome.
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Affiliation(s)
- Katherine E Scull
- Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, 30 Flemington Rd, Parkville, VIC, Australia
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32
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Kulkarni KP, Ramarathinam SH, Friend J, Yeo L, Purcell AW, Perlmutter P. Rapid microscale in-gel processing and digestion of proteins using surface acoustic waves. Lab Chip 2010; 10:1518-20. [PMID: 20517556 DOI: 10.1039/c001501f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new method for in-gel sample processing and tryptic digestion of proteins is described. Sample preparation, rehydration, in situ digestion and peptide extraction from gel slices are dramatically accelerated by treating the gel slice with surface acoustic waves (SAWs). Only 30 minutes total workflow time is required for this new method to produce base peak chromatograms (BPCs) of similar coverage and intensity to those observed for traditional processing and overnight digestion. Simple set up, good reproducibility, excellent peptide recoveries, rapid turnover of samples and high confidence protein identifications put this technology at the fore-front of the next generation of proteomics sample processing tools.
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Affiliation(s)
- Ketav P Kulkarni
- School of Chemistry, Monash University, PO Box 23, Melbourne, 3800, Australia
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33
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Petersen J, Wurzbacher SJ, Williamson NA, Ramarathinam SH, Reid HH, Nair AKN, Zhao AY, Nastovska R, Rudge G, Rossjohn J, Purcell AW. Phosphorylated self-peptides alter human leukocyte antigen class I-restricted antigen presentation and generate tumor-specific epitopes. Proc Natl Acad Sci U S A 2009; 106:2776-81. [PMID: 19196958 PMCID: PMC2650342 DOI: 10.1073/pnas.0812901106] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Indexed: 11/18/2022] Open
Abstract
Human leukocyte antigen (HLA) class I molecules present a variety of posttranslationally modified epitopes at the cell surface, although the consequences of such presentation remain largely unclear. Phosphorylation plays a critical cellular role, and deregulation in phosphate metabolism is associated with disease, including autoimmunity and tumor immunity. We have solved the high-resolution structures of 3 HLA A2-restricted phosphopeptides associated with tumor immunity and compared them with the structures of their nonphosphorylated counterparts. Phosphorylation of the epitope was observed to affect the structure and mobility of the bound epitope. In addition, the phosphoamino acid stabilized the HLA peptide complex in an epitope-specific manner and was observed to exhibit discrete flexibility within the antigen-binding cleft. Collectively, our data suggest that phosphorylation generates neoepitopes that represent demanding targets for T-cell receptor ligation. These findings provide insights into the mode of phosphopeptide presentation by HLA as well as providing a platform for the rational design of a generation of posttranslationally modified tumor vaccines.
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Affiliation(s)
- Jan Petersen
- Protein Crystallography Unit, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia; and
| | - Stephanie J. Wurzbacher
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Nicholas A. Williamson
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Sri H. Ramarathinam
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Hugh H. Reid
- Protein Crystallography Unit, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia; and
| | - Ashish K. N. Nair
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Anne Y. Zhao
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Roza Nastovska
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Geordie Rudge
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Jamie Rossjohn
- Protein Crystallography Unit, Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Victoria 3800, Australia; and
| | - Anthony W. Purcell
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
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34
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Lam AKY, Ramarathinam SH, Purcell AW, O'Hair RAJ. Can alpha- and beta-alanine containing peptides be distinguished based on the CID spectra of their protonated ions? J Am Soc Mass Spectrom 2008; 19:1743-1754. [PMID: 18964084 DOI: 10.1016/j.jasms.2008.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 09/05/2008] [Accepted: 09/05/2008] [Indexed: 05/27/2023]
Abstract
The fragmentation reactions of isomeric dipeptides containing alpha- and beta-alanine residues (alphaAla-alphaAla, alphaAla-betaAla, betaAla-alphaAla, and betaAla-betaAla) were studied using a combination of low-energy and energy resolved collision induced dissociation (CID). Each dipeptide gave a series of different fragment ions, allowing for differentiation. For example, peptides containing an N-terminal beta-Ala residue yield a diagnostic imine loss, while lactam ions at m/z 72 are unique to peptides containing beta-Ala residues. In addition, MS(3) experiments were performed. Structure-specific fragmentation reactions were observed for y(1) ions, which help identify the C-terminal residue. The MS(3) spectra of the b(2) ions are different suggesting they are unique for each peptide. Density functional theory (DFT) calculations predict that b(2) ions formed via a neighboring group attack by the amide are thermodynamically favored over those formed via neighboring group attack by the N-terminal amine. Finally, to gain further insight into the unique fragmentation chemistry of the peptides containing an N-terminal beta-alanine residue, the fragmentation reactions of protonated beta-Ala-NHMe were examined using a combination of experiment and DFT calculations. The relative transition-state energies involved in the four competing losses (NH(3), H(2)O, CH(3)NH(2), and CH(2)=NH) closely follow the relative abundances of these as determined via CID experiments.
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Affiliation(s)
- Adrian K Y Lam
- School of Chemistry, The University of Melbourne, Victoria, Australia
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