CXCR3 and proliferative glomerulonephritis: They found that CXCR3 was highly expressed in glomerular structures and localized to mesangial cells of patients with proliferative glomerulonephritis (PGN), as demonstrated by morphology and double-label immunohistochemistry with monoclonal antibodies (mAbs) against CXCR3 and α-SMA, a disease marker of mesangial cells.