CD163 and proliferative glomerulonephritis: Recent studies indicate that the population of CD163 + M2 macrophages are prevalent in renal biopsies of proliferative glomerulonephritis, such as lupus nephritis, anti-neutrophil cytoplasmic antibodies (ANCA)-associated pauci-immune necrotizing glomerulonephritis, and membranoproliferative glomerulonephritis.