CD4 and neoplasm: It was observed that CD11b+ myeloid cells were the most numerous cell population of all the tumor-infiltrating leukocytes in the MC38 control group and amounted to 65%, whereas T lymphocytes and NK cells together constituted approximately 16% (the percentage of CD4+ cells amounted to 7.5%; CD8+—6.7% and CD49b+—1.5%; Figures 4D,F).