抗肿瘤 T 细胞中 PRDM1 基因敲除增强过继免疫治疗的疗效

Adoptive cancer immunotherapy can induce objective clinical efficacy in patients with advanced cancer; however, a sustained response is achieved in a minority of cases. The persistence of infused T cells is an essential determinant of a durable therapeutic response. Antitumor T cells undergo a genome-wide remodeling of the epigenetic architecture upon repeated antigen encounters, which inevitably induces progressive T-cell differentiation and the loss of longevity. In this study, we identified PR domain zinc finger protein 1 (PRDM1) ie, Blimp-1, as a key epigenetic gene associated with terminal T-cell differentiation.

The genetic knockout of PRDM1 by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) supported the maintenance of an early memory phenotype and polyfunctional cytokine secretion in repeatedly stimulated chimeric antigen receptor (CAR)-engineered T cells. PRDM1 disruption promoted the expansion of less differentiated memory CAR-T cells in vivo, which enhanced T-cell persistence and improved therapeutic efficacy in multiple tumor models.

Mechanistically, PRDM1-ablated T cells displayed enhanced chromatin accessibility of the genes that regulate memory formation, thereby leading to the acquisition of gene expression profiles representative of early memory T cells.

PRDM1 knockout also facilitated maintaining an early memory phenotype and cytokine polyfunctionality in T-cell receptor-engineered T cells as well as tumor-infiltrating lymphocytes. In other words, targeting PRDM1 enabled the generation of superior antitumor T cells, which is potentially applicable to a wide range of adoptive cancer immunotherapies.