CTLA4 and melanoma: A deep multiparametric cytofluorimetric analysis of circulating T cells in advanced melanoma patients undergoing the combination treatment with anti-CTLA-4 mAb plus chemotherapy highlighted that increased levels in the peripheral blood of central memory T cells expressing co-stimulatory and activatory molecules (CD45RA−CD62L+ CCR7+ CD27+ CD28+ BTLA+/PD-1+) were associated with objective clinical responses [20,21].