FCGR2B and acquired epidermolysis bullosa: Although a full discussion of IVIg-Fcγ receptor biology is beyond the scope of this review, it is important to note that inhibitory FcγRIIB were required for the anti-inflammatory effects of IVIg in murine models of ITP (72), nephrotoxic nephritis (82), and epidermolysis bullosa acquisita (EBA) (54).