TNF and lupus nephritis: The M1-like macrophage subtype has long been believed to be a source of pathology in lupus nephritis [25] and the high levels of IL-6 [35, 36], IFN-ɣ [35] and TNF-α [36] found in patients with lupus nephritis support the important role of pro-inflammatory M1-like macrophages in the pathogenesis of the disease.