CD28 and central nervous system cancer: Although previous studies have demonstrated that CCR5 expression is restricted to memory (CD28+CD45RA−) and effector (CD28−CD45RA− and CD28−CD45RA+) CD8+ T cells (23), in this study we also demonstrated that CCR5 was distinctly expressed in the CD38+HLA-DR+CD8+ T-cell population characterized as TEMRA+ (CD45RA+CCR7−) from patients with glioma.