The humanized CD37-CAR-T cells specifically target CD37-positive cells. (A). The structure of humanized CD37-CAR-T cells. The structure includes CD8 signaling peptide; humanized CD37 ScFv, CD8 hinge, CD28 TM (transmembrane domain); 41BB domain; CD3 zeta activation domain. (B). FACS with mouse and human FAB detected CAR-positive cells. (C). Humanized CD37-CAR-T cells killed CHO-CD37-positive cells and did not kill CHO cells. (D). Quantification of cytotoxicity shows significantly higher killing by CD37CAR-T cells in CHO-CD37 cells than Mock and T cells. *, hCD37 CAR-T cells with CHO-CD37 cells versus T and Mock CAR-T cells, p < 0.0001, One-Way ANOVA followed by Dunnett’s Multiple Comparison Test. (E). hCD37-CAR-T cells secrete significantly higher IFN-gamma with CHO-CD37 cells than with CHO cells. *, p < 0.05, IFN-gamma of humanized Hum CD37 CAR-T cells with CHO-CD37 cells versus same CAR-T cells with CHO cells by Student’s t-test.