CD4 and B-cell chronic lymphocytic leukemia: From the clinical point of view, Tαβ CD4+CD8lo cells have been found to be expanded in response to CMV [56,57], as well as in different types of cancer, including CLL, which strongly supports its potential role in anti-tumoral immunosurveillance against HLA-II+ cells, like CLL cells [58,59,60,61].