IRF4 and common variable immunodeficiency: In patients with common variable immunodeficiency (CVID) without identified genetic defects, the terminal differentiation of B-cells was found to be affected by the overexpression of miR-125b-5p, via the down-regulation of B-lymphocyte-induced maturation protein 1 (BLIMP-1) and interferon regulatory factor 4 (IRF-4) transcription factors [98].