CD4 and neoplasm: Another engineered WR strain variant of Pexa-Vec, which expresses mGM-CSF, administered by i.t. injection in combination with anti-PD-1 antibody (aPD1), is reported to promote greater CD4+ and CD8+ T cell infiltration, tumor cell killing, and growth slowing of subcutaneous renal cell carcinomas (Rencas) in syngeneic mice and mammary tumors in MMTV-PyMT mice.10