KLRK1 and neoplasm: Ten days after the first injection of T cells, human CD4+ T cell counts were higher compared to CD8+ T cell counts in the circulation and both CD4+ and CD8+ T cells in GFP-NKG2D-z, GFP-NKG2D-BBz, and GFP-NKG2D-27z CAR cohorts were present in lower numbers in comparison to untransduced T cells, suggesting early NKG2DL-specific CAR T cell migration to specific tumor sites (Fig. 6d).