The monoclonal antibodies used in this study were: CD3-pacific blue (PB) (clone UCHT-1; Dako, Trappes, France), CD4-peridin chlorophyll protein-cyanine 5.5 (PerCP-Cy5.5) (clone L200; BD, Le-Pont-de-Claix, France), CD45RA-phycoerythrin (PE) (clone HI100; BD), CCR7-allophycocyanin (APC) (clone 150503; R&D Systems Europe, Lille, France); CD8-phycoerythrin-cyanine 7 (PE-Cy7) (RPA-T8; BD), CD31-biotin (clone WM59; AbDSerotec, Düsseldorf, Germany); Ki-67-fluorescein isothiocyanate (FITC) (clone MIB-1; Dako), Bcl-2-FITC (clone 124; Dako) and strepatavidin-PE-Texas-RED (BD).