CD8A and cancer: Chimeric antigen receptor (CAR) T cells also use this approach, with the goal of stimulating the immune response to eliminate the cancer cells.23 However, the degree to which immunosuppressive immune cells infiltrate a tumor and suppress or exclude cytotoxic CD8+ T cells exists in a wide spectrum across cancer.23–25 This serves to explain why ICB and CAR T cell therapy are ineffective against many solid tumors, and also why targeting immunosuppressive myeloid cells such as macrophages in combination with ICB has become of interest.