Vδ1 T cells exhibit high lactic acid resistance and antitumor activity in solid tumors

BACKGROUND: Vδ1 T cells are promising for solid tumor immunotherapy but limited by peripheral rarity and inefficient expansion. This study aimed to establish a scalable expansion protocol and evaluate the therapeutic potential of unmodified and CAR-engineered Vδ1 T cells. METHOD: Vδ1 T cells were expanded with a patented humanized Vδ1 TCR antibody plus cytokine cocktail (vs. commercial protocols). Transcriptomic profiling, in vitro cytotoxicity assays, in vivo xenograft experiments (vs. Vδ2 T cells), and PARP1-mediated lactate resistance analyses were performed. MSLN/NCL-targeted CAR-Vδ1 T cells were constructed and validated in OVCAR8-baring mice models. RESULTS: Average 1 × 10¹⁰ high-purity Vδ1 T cells were obtained from 10 mL peripheral blood, outperforming commercial protocols. Expanded cells retained a stem-like phenotype, exerted superior antitumor activity vs. Vδ2 T cells, and resisted lactate-induced apoptosis via high PARP1 expression. CAR and IL-15 modified Vδ1 T cells showed potent anti-tumor efficacy. CONCLUSIONS: This efficient Vδ1 T cell expansion protocol overcomes key clinical translation barriers. Vδ1 and CAR-Vδ1 T cells represent a novel off-the-shelf immunotherapeutic strategy for solid tumors.