CD4 and central nervous system cancer: The proportions of major lymphocyte subpopulations such as CD19+ B cells, CD3+ T cells, CD3+/CD4+ helper T cells, CD3+/CD8+ cytotoxic T cells, CD4+/CD25+/FoxP3+ and CD8+/CD25+/FoxP3+ Tregs, CD3+/CD56+, CD3+/CD94+, CD3+/NKG2D+ NK-like T cells (NKT), CD56+/CD94+, CD3-/CD56+, CD56+/CD69+, CD3-/CD69+, CD3-/NKG2D+, CD3-/NKp30, and CD3-/NKp40 NK cells were assessed in the peripheral blood of 75 patients with gliomas at first diagnosis (6 grade II, 13 grade III and 56 grade IV) and healthy controls (n = 15).