Thus, in addition to the B-cell defect, CVID patients might also display a) an exhausted thymic output (41) associated with significantly reduced naïve TCD4+ and naïve TCD8+ cell counts (17, 41, 42) and, b) Th1-mediated inflammatory processes (40, 59) associated with an increased frequency of circulating Th1/TFH CD4+ T-cells (44, 45, 60) and both EM and TE TCD8+ and TCRγδ+ T-cells (42, 55, 58, 61), in parallel to reduced Treg, Th2, Th17 and CM CD4+ T-cells (42, 61). This evidence concerns the gene CD4 and common variable immunodeficiency.