FCGR2A and neuromyelitis optica: The binding of the antibody Fc region to Fc gamma receptors on activated microglia/macrophages promotes their accumulation and plays an important role in NMO pathology, as evidenced by a reduction of tissue damage in NMO models involving mice lacking Fcgr3, mice treated with Fcgr blockers, or mice containing mutated NMO-IgG without ADCC function [28].