CD4 and neoplasm: Interestingly we found that treatment with Ca alone resulted in a higher frequency of CD4+ PD-1+ T cells in the tumor (V=80.3 ± 2.2, Ca =89.7 ± 1.3; p=0.006), but not the spleen, and that there was a higher frequency of PD-1+ T cells in the TILs relative to the spleen, regardless of treatment.