CD4 and neoplasm: Consistent with the effects of CCR2 gene deletion on anti-tumor responses (Figure 3), use of a CCR2 antagonist significantly increased CD8 T cell infiltration and to a lesser extent also boosted CD4+ T cell infiltration, too, and both intratumoral T cell populations had the phenotype of effector/memory T cells (CD44hi CD62Llow) (Figure 10).