In particular, it seems that pro-inflammatory cytokines could enhance the expression of microRNA-506 (miR-506) in BECs, resulting in the overexpression and mislocalization of PDC-E2 in PBC patients [61] followed by NKT cell, MAIT cell, and CD4+ and CD8+ cell infiltration around intrahepatic bile ducts [62]. This evidence concerns the gene CD4 and primary biliary cholangitis.