靶向 PTPRZ1 的 RNA CAR-T 细胞在胶质母细胞瘤中发挥抗原特异性与旁观者抗肿瘤活性

The great success of chimeric antigen receptor (CAR) T-cell therapy in the treatment of patients with B-cell malignancies has prompted its translation to solid tumors. In the case of glioblastoma (GBM), clinical trials have shown modest efficacy, but efforts to develop more effective anti-GBM CAR T cells are ongoing. In this study, we selected protein tyrosine phosphatase receptor type Z (PTPRZ1) as a target for GBM treatment.

We isolated six anti-human PTPRZ1 single-chain variable fragments from a human phage display library and produced second-generation CAR T cells in an RNA format. Patient-derived GBM PTPRZ1-knockin cell lines were used to select the CAR construct that showed high cytotoxicity while consistently displaying high CAR expression (471_28z). CAR T cells incorporating 471_28z were able to release IFN , IL2, TNF , granzyme B, IL17A, IL6, and soluble FasL and displayed low tonic signaling.

Additionally, they maintained an effector memory phenotype after in vitro killing.

In addition, 471_28z CAR T cells displayed strong bystander killing against PTPRZ1-negative cell lines after preactivation by PTPRZ1-positive tumor cells but did not kill antigen-negative nontumor cells. In an orthotopic xenograft tumor model using NOD/SCID mice, a single dose of anti-PTPRZ1 CAR T cells significantly delayed tumor growth. Taken together, these results validate PTPRZ1 as a GBM target and prompt the clinical translation of anti-PTPRZ1 CAR T cells.