Notably, FcgRIIb is the only inhibitory receptor among the Fc gamma receptor (FcgR) family, and the loss of FcgRIIb facilitates immune responses resulting in the spontaneous development of full-blown lupus nephritis (serum anti-dsDNA, proteinuria, and uremia) after 6 months in FcgRIIb-/- mice. Here, FCGR2B is linked to lupus nephritis.