Perioperative myeloid cell remodeling shapes CAR-T cell efficacy in glioblastoma

Abstract

Glioblastoma (GBM) is characterized by a profoundly immunosuppressive tumor microenvironment (TME) that constrains the efficacy of chimeric antigen receptor (CAR)-T cell therapy. Here, we show that surgical resection in both male mice and human GBM ex vivo induces a rapid and sustained remodeling of the TME, marked by upregulation of TREM2 in myeloid cells followed by emergence of T cell exhaustion-like phenotypes. In male mice, targeting TREM2 reshapes the perioperative TME and potentiates tumor antigen-specific CAR-T cell responses, improving intratumoral persistence, proliferation, and effector differentiation, and resulting in enhanced survival. In parallel, we identify the timing of CAR-T cell administration as a critical determinant of therapeutic outcome, with neoadjuvant outperforming adjuvant treatment by preserving CAR-T cell effector function in mice. These findings establish perioperative myeloid cell remodeling and treatment timing as key determinants of CAR-T cell efficacy in GBM. Glioblastoma (GBM) is characterized by an immunosuppressive tumor microenvironment (TME). Here the authors report that surgical resection induces TREM2 associated immunosuppressive remodeling of the TME and test CAR-T based strategies to reshape the perioperative GBM TME.