CD4 and type 1 diabetes mellitus: The stimulation of CD3+CD4+ cells with 25(OH)D3 [62.4 nM] and 1,25(OH)2D3 [1 × 10−8 M] for 72 h revealed a reduced percentage of CD4+ cells isolated from T1D patient carrying “FF”, suggesting a beneficial balance in the T cell compartment [116].