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Benitez-Ribas, D.

Publications and source records attributed to Benitez-Ribas, D..

3 recordsLinked to original sources

Integrative single-cell multi-omics of CD19CARpos and CARneg T cells suggest drivers of immunotherapy response in B-cell neoplasias

How phenotypic, clonal, and functional heterogeneity of CAR-T-cells impact clinical outcomes remain understudied. Here, we integrated clonal kinetics with transcriptomic heterogeneity resolved by single-cell omics to explore cellular dynamics response of both non-transduced (CARneg) and transduced (CARpos)T-cells. CARneg and CARposT-cells were longitudinally interrogated in the manufactured infusion product (IP) and in-vivo at CAR-T cell expansion peak in five B-ALL patients treated with CD19CAR-T-cells (varni-cel). Significant differences were found in the cellular dynamics between CARpos and CARnegT-cells in response to therapy. CARposT-cells in the IP exhibited a significant higher CD4:CD8 ratio than CARnegT-cells, and the CD4:CD8 CARposT-cell composition impacted therapy outcome as confirmed in a larger cohort of 24 varni-cel-treated B-ALL patients. Conversely, an inverted trend in the CD4:CD8 CARposT-cell ratio was consistently observed at the expansion peak, with clonally expanding CD8+ effector memory and cytotoxic T-cells being the most abundant populations. Expanded cytotoxic CARpos{gamma}{delta}T cells emerged at the expansion peak, and the extent of their in-vivo expansion positively correlated with treatment efficacy, which was validated in a large cohort of B-ALL patients (n=18) treated with varni-cell and B-cell lymphoma patients (n=58) treated with either lisa-cel or axi-cel. Our data provide insights into the complexity and diversity of T-cell responses following CAR-T cell therapy and suggest drivers of immunotherapy response.

immunology↗

Immunofilaments Provide a Nanoscale Platform for In Vivo T Cell Expansion and Cancer Immunotherapy

Adoptive T cell therapy has successfully been implemented for the treatment of cancer. Nevertheless, the precarious ex vivo expansion of T cells by artificial antigen-presenting cells (aAPCs) remains cumbersome and can compromise T cell functionality, thereby limiting their therapeutic potential. Here, we propose a radically different approach aiming at direct expansion of T cells in vivo, thereby omitting the need for large-scale ex vivo T cell production. We engineered nanosized immunofilaments (IFs), consisting of a soluble semiflexible polyisocyanopeptide polymer backbone that presents peptide-loaded major histocompatibility complexes and co-stimulatory molecules in a multivalent fashion. We demonstrate that IFs readily activate and expand antigen-specific T cells in a manner highly similar to natural APCs, as evidenced by transcriptomic analyses of T cells. Upon intravenous injection, IFs reach lymphoid organs including spleen and lymph nodes and induce antigen-specific T cell responses in vivo. Moreover, IFs display remarkable anti-tumor efficacy resulting in inhibition of melanoma metastases formation and reduction of primary tumor growth in synergy with immune checkpoint blockade. In conclusion, nanosized IFs represent a powerful new type of aAPC that provide a modular platform for direct activation and expansion of antigen-specific T cells in vivo, which can greatly contribute to cancer immunotherapy.

immunology↗

Membrane receptor MerTK is a newly identified transcriptional regulator that associates to chromatin as nanoclusters during human DC differentiation

MerTK is a transmembrane receptor tyrosine kinase (RTK) mainly expressed in dendritic cells (DCs) and macrophages where it plays an important role in immunotolerance, but also in activating oncogenic signalling pathways. Albeit MerTK is exploited as clinical target in cancer and auto-immune disorders, the mechanisms that regulate its diverse functions are poorly understood. Here, we identified a remarkably high pool of the full receptor in the nucleus of human DCs. Nuclear translocation was ligand-dependent. Importantly, MerTK nuclear levels correlated to DC differentiation and were spatiotemporally regulated by the transmembrane receptor LRP-1. Using dual-colour super-resolution nanoscopy we discovered that nuclear MerTK forms nanoclusters, whose strength strongly depends on chromatin accessibility during DC differentiation. We finally revealed high transcription capacity of MerTK. Overall, our work indicates that nuclear MerTK acts as a transcription factor regulating DC differentiation, thus implicating for the first time a physiological function for RTK nuclear translocation in immunity.

immunology↗