Project description:We introduced single-chain trimer (SCT) technologies into a high throughput platform for pMHC library generation that can be used for screening antigen specific CD8+ T cells. We compared the diversity of T cell receptor repertoire captured by SCT and folded peptide-MHC multimer presenting HLA-A02:01 restricted CMV peptide. We then constructed SCT libraries designed to capture SARS-CoV-2 spike specific CD8+ T cells from COVID-19 participants and healthy donors. TCR sequencing with antigen specificity was analyzed. The immunogenicity of these epitopes was validated by functional assays of T cells with cloned TCRs captured using SCT libraries.
Project description:HLA-E molecules can present self and pathogen-derived peptides to both NK-cells and T-cells. T-cells that recognize HLA-E peptides via their T-cell receptor (TCR) are termed donor-unrestricted T-cells due to restricted allelic variation of HLA-E. The composition and repertoire of HLA-E TCRs is not known so far. We performed TCR sequencing on CD8+ T-cells from 21 individuals recognizing HLA-E tetramers (TM) folded with 2 Mtb HLA-E restricted peptides. We sorted HLA-E Mtb TM+ and TMCD8+ T-cells directly ex vivo and performed bulk RNA-sequencing and single cell TCR sequencing. The identified TCR repertoire was diverse and showed no conservation between and within individuals. TCRs selected from our single cell TCR sequencing data could be activated upon HLA-E/peptide stimulation, although not robust, reflecting potentially weak interactions between HLA-E peptide complexes and TCRs. Thus, HLA-E Mtb specific T-cells have a highly diverse TCR repertoire.
Project description:HLA DRB1*15:01 is overrepresentated in Parkinson's disease patients and binds with high affinity to the ⍺-synuclein peptide, 32-46. Immunization of humanized mice expressing HLA DRB1*15:01 with ⍺-syn32-46 induces enteric phenotypes similar to those of prodromal Parkinson's disease. We collected the small intestines from HLA mice immunized with either Complete Freund's Adjuvant (CFA) with ⍺-syn32-46 or CFA alone, sorted the CD45+ immune cells, then performed single-cell RNA sequencing to evaluate gene expression at single cell resolution.
Project description:HLA DRB1*15:01 is overrepresentated in Parkinson's disease patients and binds with high affinity to the ⍺-synuclein peptide, 32-46. Immunization of humanized mice expressing HLA DRB1*15:01 with ⍺-syn32-46 induces enteric phenotypes similar to those of prodromal Parkinson's disease. We collected the ileum from HLA mice immunized with either Complete Freund's Adjuvant (CFA) with ⍺-syn32-46 or CFA alone, and sequenced the tissue with bulk RNA sequencing at 21 days post immunization to determine changes in gene expression.
Project description:DNA methyltransferase 3A (DNMT3A) and isocitrate dehydrogenase 1 & 2 (IDH1/2) are genes involved in epigenetic regulation, each mutated in 7-23% of acute myeloid leukemia (AML). Here, we investigated whether hotspot mutations in these genes encode neoantigens that can be targeted by immunotherapy. Five EBV-B cell lines expressing common HLA class I alleles were transduced with a minigene construct containing mutations that often occur in DNMT3A or IDH1/2. Peptides eluted from HLA class I alleles on these EBV-B cell lines were analyzed by tandem mass spec-trometry. We identified an HLA-A*01:01-binding DNMT3AR882H peptide and HLA-B*07:02-binding IDH2R140Q peptide, for which we searched for specific T cells in healthy individuals using pep-tide-HLA tetramers. Various T-cell clones were isolated showing specific reactivity against cell lines transduced with full-length DNMT3AR882H or IDH2R140Q genes, while cell lines transduced with wildtype genes were not recognized. One T-cell clone for DNMT3AR882H also reacted against patient AML cells with the mutation, while AML cells without the mutation were not recognized, thereby validating surface presentation of a DNMT3AR882H neoantigen that can potentially be targeted on HLA-A*01:01 positive AML by immunotherapy.
Project description:Several HLA allelic variants have been associated with protection from, or susceptibility to infectious and autoimmune diseases. Here, we examined whether specific HLA alleles would be associated with different Mtb infection outcomes. We found that DQA1*03:01, DPB1*04:02, and DRB4*01:01 were signficantly more frequent in inividuals with active TB (susceptibility alleles). Furthermore, individuals who express any of the three susceptibility alleles were associated with lower magnitude of responses against Mtb antigens. We investigated the gene expression changes induced in PBMCs by Mtb lysate and a peptide pool (MTB300) in individuals with or without expression of the susceptibility alleles.
Project description:Phase I Study of NT-175, an autologous T cell therapy product genetically engineered to express an HLA-A*02:01-restricted T cell receptor (TCR), targeting TP53 R175H mutant solid tumors.
Project description:Background Clinical success of T cell receptor (TCR) gene therapy has previously been demonstrated for NY-ESO-1 TCR gene therapy. To increase numbers of cancer patients that can be treated with TCR gene therapy we aimed to identify a novel set of high-affinity cancer specific TCRs targeting different cancer testis (CT) antigens in prevalent HLA class I alleles. Methods In this study, we selected based on publicly available gene expression databases the most promising CT genes to target. From these selected genes we identified by HLA peptidomics the naturally processed and presented HLA class I peptides. With these peptide-HLA tetramers were generated, and by single cell sorting CT specific CD8+ T cells were selected, and expanded from the allo-HLA repertoire of healthy donors. By several functional assays high avidity CT-specific T cell clones with safe recognition pattern were selected. To evaluate the potential for clinical application in TCR gene therapy, TCRs were sequenced and transferred into peripheral blood derived CD8+ T cells. Results In total we identified, 7 novel CT-specific TCRs that effectively target MAGE-A1, MAGE-A3, MAGE-A6 and MAGE-A9 in the context of human leukocyte antigen(HLA) -A1, -A2, -A3, -B7, -B35 and -C7. TCR gene transfer into CD8⁺ T cells resulted in efficient cytokine production and cytotoxicity of variety of different tumor types without detectable cross-reactivity. In addition, major in vivo antitumor effects of MAGE-A1 specific TCR engineered CD8⁺ T cells was observed in an orthotopic xenograft model for established multiple myeloma, in which bone marrow located tumor cells were completely eradicated after T cell injection. Conclusion The identification of 7 novel CT-specific TCRs, reactive against CT antigens presented in a variety of different HLA class I alleles, allows selection of therapeutic TCRs for an increased number of cancer patients, and will improve development of personalized TCR gene therapy.