Platelet-derived growth factor: A potentially important cytokine in glomerular disease

Many glomerular diseases, including IgA nephropathy, membranoproliferative glomerulonephritis (GN), variants of idiopathic focal sclerosis, and lupus nephritis are characterized by mesangial cell proliferation. There is increasing evidence that mesangial cell proliferation in GN may not be a benign process, but may be associated with activation of the mesangial cell, as reflected by the acquisition of a smooth muscle cell-like pheno-type [1] and by the synthesis and secretion of increased amounts of normal and abnormal mesangial matrix components [2] and proteinases (David Lovett, manuscript submitted). Thus, an understanding of the mechanisms that initiate and maintain the proliferative response in active GN may provide useful insights into future therapeutic strategies of these diseases