EXPRESSION OF MONOCYTE CHEMOATTRACTANT PROTEIN-1 IN EXPERIMENTAL CRESCENTIC GLOMERULONEPHRITIS IN RATS

Crescentic glomerulonephritis (CGN) is a rapidly progressive glomerula r disease that is usually associated with a poor prognosis, Monocytes/ macrophages are frequently observed in glomeruli in cases of CGN, and they are considered to play a crucial role in the pathogenesis of this disease, In this study we analyzed the glomerular expression of monoc yte chemoattractant protein-1 (MCP-1), a potent chemoattractant for mo nocytes, in an experimental model of CGN. A model of the disease was i nduced in the WKY strain of rats by intravenous injection of antiserum raised against glomerular basement membranes. Accumulation of monocyt es/macrophages in glomeruli was observed 4 hours after the injection o f antiserum, Northern blot analysis showed that the expression of mRNA for MCP-1 was enhanced within 4 hours, peaked on day 3-when it was 60 times that in the control-and then declined. Immunostaining with MCP- 1-specific antibody revealed the expression of MCP-1 protein in the di seased glomeruli but not in control glomeruli. Quantitative analysis o f glomerular MCP-1 protein by enzyme-linked immunosorbent assay reveal ed a level 46 times that in the control in reflecting the increase in mRNA for MCP-1, These results indicate that glomeruli of rats with CGN produce MCP-1, which may play an important role in the pathogenesis o f glomerular inflammation and crescent formation in CGN.