TNFSF12 and type 2 diabetes mellitus: Increased levels of the receptors sTNF-R1, sTNF-R2, sCD30/TNFRSF8, and the ligands TVVEAK/TNFSF12, APRIL/TNFSF13, BAFF/TNFSF13B are characteristic of obese patients without T2DM.