CD40 and systemic lupus erythematosus: More importantly, many of the markers on M1 macrophages were found to remarkably ascend in SLE serum, which were implicated in the pathogenesis of SLE [114, 115]; for instance, BAFF, a member of TNF superfamily originating from M1 and an enhancement factor of M1 polarization [116, 117], primarily participates in stimulating B cell activation [118]; costimulatory molecules CD40 and CD86 also improve the ability of M1 to activate B cells and facilitate autoantibody production [119, 120].