Dataset Information

Eradication of tumors with pre-existing antigenic heterogeneity by vaccine-mediated co-engagement of CAR T and endogenous T cells

ABSTRACT: Chimeric Antigen Receptor (CAR) T-cell therapy can be effective in treating human cancer but, loss/downregulation of the antigen recognized by the CAR poses a major obstacle to tumor eradication. Here, we report an approach for vaccine boosting CAR T-cells, which triggers engagement of the endogenous immune system to stop antigen-negative tumor escape. Vaccine boosting enhanced CAR T-cell polyfunctionality, increased tumor antigen uptake by dendritic cells, and elicited priming of endogenous anti-tumor T cells (antigen spreading). This process required vaccine-induced enhancements in CAR T IFN-γ production and a metabolic shift in CAR T-cells toward oxidative phosphorylation. Antigen spreading induced by vaccine-boosted CAR-T therapy enabled control of solid tumors with substantial pre-existing heterogeneity, which was further enhanced by genetically amplifying CAR T IFN-γ expression. Thus, CAR T cell-derived IFN-γ plays a critical role in promoting endogenous anti-tumor immunity, and vaccine boosting provides a clinically-translatable strategy to drive such responses against solid tumors.

ORGANISM(S): Mus musculus

PROVIDER: GSE211938 | GEO | 2025/08/07

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Anti-cancer immunotherapy approaches are increasingly coveted. Chimeric antigen receptor (CAR)-T cell therapy has been shown to be an effective treatment for hematological tumors, but the treatment of solid tumors still lacks effectiveness, due to lower intra-tumor infiltration of CAR-T cells and tumor-induced immunosuppression. Macrophages represent a very large proportion of the tumor environment, participate in many aspects to tumor development and therefore represent interesting therapeutic targets. Macrophages can infiltrate solid tumor tissue and interact with almost all cellular components in the tumor microenvironment. In addition, macrophages can also promote a direct anti-tumor response by phagocyting tumor cells. We have developed macrophages expressing a CAR receptor against the HER2 antigen. The CAR receptor possesses an intracellular domain CD3ζ having homology with the protein FcεRI-γ, which once activated by the recognition antibody-antigen, induces the phagocytic activity of macrophages. 72% of macrophages express the CAR after transduction. CAR-M can specifically phagocyte HER2 coated-beads in a much more effective way than WT macrophages. We have then confirmed the capacity of CAR-M to phagocyte HER2+ cancer cell lines. Co-culture of CAR-M with breast cancer tumoroids (HER2+ or HER2-) has also been performed demonstrating their efficacy in a more complex environment. However, in the tumor microenvironment, due to their plasticity, macrophages tend to adopt an anti-inflammatory phenotype losing their anti-tumor activities. We have therefore developed a combined strategy by inhibiting two proprotein convertases, Furin and PC1/3 in CAR-M. The inhibition of furin or PC1/3 induces an increase in pro-inflammatory markers and maintains macrophage activation in the presence of cancer cells. In addition, HER2+ CAR-M with shFurin or shPC1/3 greatly increases the phagocytic activity on Her2+ beads or Her2+ tumors. These enzymes are therefore phenotypic regulators of macrophages. Our strategy is therefore based on a double activation of tumor-infiltrating macrophages. The first one consists in boosting the phagocytic activity of macrophages by having them express a CAR receptor targeting a tumor antigen. The second allows their reprogramming towards a pro- inflammatory phenotype by the inhibition of Furin and/or PC1/3 proprotein convertases

Project description:All nucleated mammalian cells express major histocompatibility complex (MHC) proteins that present peptides on cell surfaces for immune surveillance. These MHC-presented peptides (pMHC) can convey non-self antigens derived from pathogens or mutations to amount T-cell responses. Alterations in tumor-specific antigens – particularly mutation-bearing peptides (neoantigens) presented by MHC — can serve as potent substrates for anti-tumor immune responses. Here we employed an integrated genomic and proteomic antigen discovery strategy aimed at measuring interferon gamma (IFN-γ) induced alterations to antigen presentation, using a lymphoma cell line. IFN-γ treatment resulted in a set of differentially expressed proteins (2 % of all quantified proteins) including components of antigen presentation machinery or interferon signaling pathways. In addition, several proteasome subunits were found to be modulated, consistent with previous reports of immunoproteasome induction by IFN-γ exposure. This finding suggests that a modest proteomic response to IFN-γ could create larger alteration to cells antigen repertoires. Accordingly, by surveying immunopeptides, distinct peptide repertoires were exclusively observed in the IFN-γ induced samples. Furthermore, an additional set of presented peptides distinguished control and the IFN-γ samples by their altered relative abundances including neoantigens. Accordingly, we developed a classification system to distinguish peptides which are differentially presented due to altered expression from novel peptides resulting from changes in antigen processing. Taken together, these data demonstrate that IFN-γ can re-shape antigen repertoires by identity and by abundance. Extending this approach to models with greater clinical relevance should help develop strategies by which immunopeptide repertoires are intentionally reshaped to improve endogenous or vaccine-induced anti-tumor immune responses and potentially anti-viral immune responses.

Dataset Information

Eradication of tumors with pre-existing antigenic heterogeneity by vaccine-mediated co-engagement of CAR T and endogenous T cells

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets