IFNGR1 and systemic lupus erythematosus: Furthermore, although the total number of synaptic inclusions in phagocytic microglia was reduced in anti-IFNγR–treated lupus mice, we cannot exclude the presence of other potential activators of microglial phagocytosis in lupus mice, as neuron-derived factors can also evoke phagocytosis via phagocytic receptors on microglia (50).