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Vega, F.

Publications and source records attributed to Vega, F..

6 recordsLinked to original sources

A novel KIR3DL2-directed CAR T-cell therapy for cutaneous and systemic T-cell lymphomas

Chimeric antigen receptor (CAR) T-cell therapy has transformed the treatment of B-cell malignancies and multiple myeloma, but its extension to T-cell lymphomas (TCLs) has been constrained by the paucity of antigens that can be safely targeted. While targeting pan-T antigens broadens the therapeutic reach across various TCLs, it carries a substantial risk of immunosuppression and infection. Here, we report killer cell immunoglobulin-like receptor, three Ig domains and long cytoplasmic tail 2 (KIR3DL2/CD158k) as a viable target for CAR T-cell therapy against a wide range of TCLs. Using single-cell RNA-seq data analysis and flow cytometric phenotyping, we observed that KIR3DL2 expression is restricted to a subset of mature NK cells and a minor fraction of CD8 T cells, with negligible expression in other healthy adult tissues. Among TCLs, KIR3DL2 expression was noted in various subtypes of cutaneous and systemic TCLs. Anti-KIR3DL2 CAR constructs (3DL2CARs) efficiently and selectively redirected T cells against antigen-positive cell lines but not isogenic KIR3DL2-negative counterparts, with antigen-specific signaling, cytotoxicity, proliferation, and cytokine production. Importantly, 3DL2CART cells produced sustained tumor regression and prolonged survival in two distinct cell line-derived xenograft models of cutaneous TCL and in one patient-derived xenograft model of hepatosplenic TCL. 3DL2CART cells exhibited minimal off-target activity against bystander immune cells and showed no appreciable fratricide. To mitigate the risk of tumor cell contamination in autologous CAR T-cell products, we established a two-tiered strategy that integrates immunomagnetic depletion of KIR3DL2-positive tumor cells with in vivo activation of a safety switch if inadvertently transduced malignant cells contribute to immune escape. Together, our results establish the preclinical efficacy and safety of 3DL2CART-cell therapy and support its clinical translation. This approach may offer a targeted alternative to pan-T-cell-directed CAR T-cell strategies for patients with relapsed/refractory cutaneous and systemic TCLs, addressing a critical unmet clinical need.

immunology↗

A patient derived xenograft repository capturing clinical and molecular heterogeneity of large B-cell lymphoma

Large B-cell lymphomas (LBCLs) are a clinically and molecularly diverse group of malignancies with a rapidly evolving therapeutic landscape that has introduced new areas of clinical need such as post-CD19 chimeric antigen receptor T (CART19) progression. Patient derived xenograft (PDX) models are an important tool for mechanistic studies and preclinical evaluation of new therapies and can be generated from a variety of clinical contexts that capture tumor-intrinsic resistance mechanisms. We therefore undertook a comprehensive effort to generate PDX models that encompass the molecular landscape of LBCLs and include important clinical scenarios for new drug development. Here we describe the first 48 models within this publicly available repository, capturing the transcriptional and genetic subsets of LBCL. These models also include 23 generated from post-CART progression biopsies which reproduce patterns of progression driven by CD19 mutation or expression loss, as well as tumor cell-intrinsic CART19 resistance that we validate in vivo. STATEMENT OF SIGNIFICANCEYang et al. describe X-LYMPH (Xenografts of Lymphoma), a publicly available and molecularly annotated PDX repository that captures the heterogeneity of large B-cell lymphoma. X-LYMPH includes models of chimeric antigen receptor T cell resistance, providing a shared foundation for mechanistic research and therapeutic development for lymphomas.

cancer biology↗

Microbial metabolism of food allergens determines the severity of IgE-mediated anaphylaxis

Anaphylaxis is an acute, potentially life-threatening reaction, often triggered by foods and largely mediated by IgE. Critically important to anaphylaxis are the factors that modulate its severity. The human microbiota is known to influence oral tolerance, but the microbial mechanisms directly involved in IgE-mediated anaphylaxis remain unknown. Here, we demonstrate that human saliva and jejunum harbor peanut-degrading bacteria that metabolize immunodominant allergens (Ara h 1 and 2) and alter IgE-binding. Additionally, we provide in vivo evidence that oral bacteria metabolize peanut allergens, influencing systemic allergen exposure and anaphylaxis severity. Finally, in clinical studies, we observe that common peanut-degrading bacteria, such as Rothia, from the oral cavity, are more abundant in peanut-allergic patients who exhibit better tolerance to allergen exposure. Altogether, these results demonstrate that human microbiota modulates IgE-mediated reactions through allergen metabolism. We reveal a novel microbial mechanism with potential to prevent, or reduce, the severity of IgE-mediated anaphylaxis.

immunology↗

Multidimensional single-cell analysis identifies a role of CD2-CD58 interactions for clinical antitumor T cell responses

The in vivo persistence of adoptively transferred T cells is predictive of anti-tumor response. Identifying functional properties of infused T cells that lead to in vivo persistence and tumor eradication has remained elusive. We profiled CD19-specific CAR T cells that comprise the infusion products used to treat large B cell lymphomas using high-throughput single-cell technologies based on Timelapse Imaging Microscopy In Nanowell Grids (TIMING) that integrates killing, cytokine secretion, and transcriptional profiling. Our results show that the directional migration of CD19-specific CAR T cells is correlated with polyfunctionality. We identified that CD2 on T cells is associated with directional migration and that the interaction between CD2 on T cells and CD58 on lymphoma cells accelerates killing and serial killing. Consistent with this, we observed elevated CD58 expression on pre-treatment tumor samples in patients with relapsed or refractory large B cell lymphomas treated with CD19-specific CAR T cell therapy was associated with complete clinical response and survival. These results highlight the importance of studying dynamic T-cell tumor cell interactions in identifying optimal antitumor responses. KEY POINTS- Profiling patient infusion products revealed that polyfunctional CAR T cells show directional migration, which is associated with higher CD2 expression - The ligand for CD2, CD58 is expressed at higher levels in the tumors of lymphoma patients who respond better to CAR T cell treatment

immunology↗

Immune microenvironment subtypes and association with tumor cell mutations and antigen expression in follicular lymphoma.

Follicular lymphoma (FL) is a B-cell lymphoma with a complex tumor microenvironment that is rich in non-malignant immune cells. We applied single-cell RNA-sequencing to characterize the diverse tumor and immune cell populations of FL and identified major phenotypic subsets of FL T-cells including a novel cytotoxic CD4 T-cell population. Their relative proportions of T-cells defined four major FL subtypes, characterized by differential representation or relative depletion of distinct T-cell subsets. By integrating exome sequencing, we observed that somatic mutations are associated with, but not definitive for, reduced antigen presentation on FL cells. In turn, expression of MHC class II genes by FL cells was associated with significant differences in the proportions and targetable immunophenotypic characteristics. This provides a classification framework of the FL microenvironment, their association with FL genotypes and antigen presentation, and informs different potential immunotherapeutic strategies based upon tumor cell MHC class II expression. Statement of significanceWe have characterized the FL-infiltrating T-cells, identified cytotoxic CD4 T-cells as an important component, showed that the abundance of these T-cell populations is associated with tumor-cell-intrinsic characteristics, and identified sets of targetable immune checkpoints on T-cells that differed between FLs with normal versus low antigen presentation.

cancer biology↗

An Out-of-Patagonia dispersal explains most of the worldwide genetic distribution in Saccharomyces eubayanus

Saccharomyces eubayanus represents missing cryotolerant ancestor of lager yeast hybrid and can be found in Patagonia in association with Nothofagus forests. The limited number of isolates and associated genomes available has prevented to resolve the S. eubayanus origin and evolution. Here, we present a sampling effort at an unprecedented scale and report the isolation of 160 strains from ten sampling sites along 2,000 km distance in South America. We sequenced the genome of 82 strains and, together with other 25 available genomes, performed comprehensive phylogenetic analysis. Our results revealed the presence of three main Patagonia-B lineages together with dozens of admixed strains distributed in three mosaic clusters. The PB-1 lineage isolated from Tierra del Fuego exhibited the highest genetic diversity, lowest LD blocks and highest Fis values compared to the other lineages, suggesting a successful adaptation to cold temperatures in extreme environments and greater inbreeding rates in Tierra del Fuego. Differences between lineages and strains were found in terms of aneuploidy and pangenome content, evidencing a lateral gene transfer event in PB-2 strains from an unknown donor species. Overall, the Patagonian lineages, particularly southern populations, showed a greater global genetic diversity compared to Holarctic and Chinese lineages, supporting the scenario of a S. eubayanus colonization from Patagonia and then spread towards northern and western regions, including the Holarctic (North America and China) and New Zealand. Interestingly, fermentative capacity and maltose consumption resulted negatively correlated with latitude, indicating a better fermentative performance in norther populations. Our genome analysis together with previous reports in the sister species S. uvarum strongly suggests that the S. eubayanus ancestor could have originated in Patagonia or the Southern Hemisphere, rather than China, yet further studies are needed to resolve this conflicting scenario. Understanding S. eubayanus evolutionary history is crucial to resolve the unknown origin of the lager yeast and might open new avenues for biotechnological applications.

genomics↗