Fig. 1.

Adoptive T-cell therapies in chronic lymphocytic leukemia. T-cell mediated therapies include the adoptive transfer of allogeneic T cells as part of hemopoietic stem cell transplantation, the transfer of allogeneic or autologous T cells with a transgenic T-cell receptor, and the transfer of T cells with chimeric antigen receptors (CARs). Early studies used CARTcells without a co-stimulatory domain (1st generation). Current trials are using 2nd-generation CAR T cells, with either a CD28 or CD137 (4-1BB) co-stimulatory domain. Preclinical studies are investigating the combination of co-stimulatory domains (3 rd generation)