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Boschert, T.

Publications and source records attributed to Boschert, T..

5 recordsLinked to original sources

Conserved programs and specificities of T cells targeting hematological malignancies

T cell-mediated immune surveillance is critical for cancer control, yet its endogenous effectiveness in hematological malignancies remains limited and poorly understood. Here, we integrate single-cell T cell receptor (TCR) profiling, HLA immunopeptidomics and functional antigen mapping to dissect the specificity landscape of bone marrow lymphocytes (BMLs) in multiple myeloma (MM) and acute myeloid leukemia (AML). We identify a rare subset of tumor-reactive T cells that exhibit a stereotyped transcriptional state distinct from bystander and virus-specific populations. Across both malignancies, immunopeptidomic profiling uncovers a partially conserved antigen repertoire enriched for noncanonical peptides, including products of novel or unannotated open reading frames (nuORFs), pseudogenes, and clonotypic immunoglobulin sequences. Several of these epitopes are recurrently presented and associated with convergent TCR responses across individuals. Based on this immune architecture, we develop a TCR-intrinsic fitness model that infers BML tumor specificity from transcriptional cues and stratifies immunotherapy response across three independent patient cohorts. Together, these findings map the latent potential of endogenous anti-tumor immunity in two biologically distinct diseases and provide a framework for decoding and restoring productive immune surveillance of hematological malignancies. HighlightsO_LISingle-cell resolved TCR profiling maps rare tumor-reactive T cells in the bone marrow of multiple myeloma (MM) and acute myeloid leukemia (AML) reveals conserved transcriptional programs C_LIO_LIA shared immunopeptidome across MM and AML includes noncanonical epitopes from nuORFs and idiotype sequences C_LIO_LIConserved tumor antigens elicit convergent T cell responses across patients C_LI O_LIA TCR fitness model predicts tumor specificity in bone marrow lymphocytes and stratifies immunotherapy response in both hematological malignancies C_LI

immunology↗

makeTCR: a Flexible Platform for Rapid, Scalable, Single-Step T Cell Receptor Synthesis

Personalised cell therapies utilising T cell receptors (TCRs) show tremendous clinical promise, though TCR synthesis and validation techniques lag behind our ability to sequence TCR repertoires. To address this gap, we developed makeTCR: a flexible modular, scalable TCR cloning system that enables single-step, 100% fidelity assembly of {beta} and {gamma}{delta} TCRs into commonly used expression vectors. By implementing cell-free manufacturing, makeTCR enables patient-derived TCRs to be functionally validated within 48 hours. We provide an open-source, easily extensible, web-based graphical platform that integrates existing tools to simplify and standardise the manufacture of TCRs across all scales of synthesis.

immunology↗

T-FINDER: A highly sensitive, pan-HLA platform for functional T cell receptor and ligand discovery

Effective, unbiased, high-throughput methods to functionally identify both class II and class I HLA-presented T cell epitopes and their cognate T cell receptors (TCRs) are essential for and prerequisite to diagnostic and therapeutic applications, yet remain underdeveloped. Addressing this bottleneck, we established T-FINDER (T cell Functional Identification and (Neo)-antigen Discovery of Epitopes and Receptors), a platform that rapidly deconvolutes CD4 and CD8 TCR reactivities to targets physiologically processed and presented by an individuals unmanipulated, complete HLA haplotype. By using a highly sensitive TCR signaling reporter capable of detecting even low-affinity TCR:ligand interactions, T-FINDER not only robustly identifies unknown peptide:HLA ligands from complex antigen libraries, but also rapidly screens and functionally validates the specificity of complex TCR libraries against known or predicted targets. To demonstrate its pan-HLA presentation capacity, we apply the platform to multiple TCR-based applications, including glioma, celiac disease, and rheumatoid arthritis, providing unique biological insights and showcasing T-FINDERs potency and versatility.

immunology↗

Neoepitope-specific vaccination of a patient with diffuse midline glioma targeting H3K27M induces polyclonal B and T cell responses across diverse HLA alleles

H3K27M, a driver mutation with T- and B-cell neoepitope characteristics, defines an aggressive subtype of diffuse glioma with poor survival. We functionally dissect the immune response of one patient who was treated with an H3K27M peptide vaccine and subsequently entered complete remission. The vaccine robustly expanded class II HLA-restricted peripheral H3K27M-specific T cells. Using functional assays, we characterized 34 clonally unique H3K27M-reactive T cell receptors and identified critical, conserved motifs in their CDR3 regions. Using detailed HLA mapping, we further demonstrate that diverse HLA-DQ, and -DR alleles present immunogenic H3K27M epitopes. Furthermore, we identified and profiled H3K27M-reactive B cell receptors from activated B cells in the cerebrospinal fluid. Our results uncover the breadth of the adaptive immune response against a shared clonal neoantigen across multiple HLA allelotypes and support the use of class II-restricted peptide vaccines to stimulate tumor-specific T and B cells harboring receptors with therapeutic potential.

cancer biology↗

ARDitox: platform for the prediction of TCRs potential off-target binding

Cellular immunotherapies, such as those utilizing T lymphocytes expressing native or engineered T cell receptors (TCRs), have already demonstrated therapeutic efficacy. However, some high-affinity TCRs have also proved to be fatal due to off-target immunotoxicity. This process occurs when the immune system acts against epitopes found on both tumor cells and healthy tissues. Moreover, some TCRs can be cross-reactive to epitopes with highly dissimilar sequences. To address this issue, we developed ARDitox, a novel in silico method based on computational immunology and artificial intelligence (AI) for predicting and analyzing potential off-target binding. We tested the performance of ARDitox in silico on different cases found in the literature where TCRs were used to target cancer-related antigens, as well as on a set of TCRs targeting a viral epitope. ARDitox was able to identify previously reported cross-reactive epitopes in line with the data available in the literature. In addition, we investigated a TCR targeting an HLA-A*02:01-restricted immunodominant epitope from the glioblastoma-associated antigen NLGN4X, identifying a cross-reactive ADH1A epitope that would not be detected in murine models. In conclusion, our in silico approach is a powerful tool that identifies potential off-target epitopes, complementing preclinical studies in developing safer cell therapies targeting tumor(- associated) antigens.

immunology↗