The Conflicting Role of Myeloid Cells in CAR-T Cell Therapy

Chimeric antigen receptor T (CAR-T) cell therapy is revolutionizing cancer treatment in hematological malignancies, but challenges related to the tumor microenvironment have hindered CAR-T success, especially in solid tumors. Myeloid cells in particular have been implicated in CAR-T efficacy. In this review, we discuss the roles of myeloid cells in CAR-T-associated toxicities including cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, and immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome, along with strategies to treat these toxicities by modulating myeloid cells. The review also explores myeloid cell-mediated suppression or enhancement of CAR-T function. Finally, strategies employed to target myeloid cells in combination with CAR-T cell therapy will be investigated.