CD38 regulates the metabolism and the immunomodulation of tumor microenvironments, making it an essential component to anti-cancer therapies. Researchers at Nationwide Children’s Hospital developed a novel technology using CD38 as a new insertion site for NK and T cells. They generated CAR-NK and CAR-T cells by integrating the DNA encoding CAR in the CD38 locus to enhance anti-tumor activity and improve metabolic function of NK and T cells. Additionally, this can be used in combination with CD38 monoclonal antibodies without risking fratricide.