CD4 and neoplasm: The affinity of DMF5 (Kd 40 μM) (115) was higher than DMF4, but interestingly still lower than the murine wild-type receptor 2C (Kd 30 μM) [Note: like DMF5, the 2C TCR exhibited some activity in CD4 T cells in vitro, although in vivo anti-tumor activity of CD4 T cells with the 2C TCR was less effective than the higher-affinity TCR m33, with a Kd of 30 nM (76)].