Chemokine gene expression in anti-glomerular basement membrane antibody glomerulonephritis. Tang, Winson W., Songmei Yin, Arthur J. Wittwer, Meiying Qi. Department of Anatomic Pathology, Amgen Inc., Thousand Oaks, CA 91320 and Monsanto Corporate Research, Monsanto Company, St Louis, MO 63167
APStracts 2:0071F, 1995.
Chemokines may be important in the pathogenesis of glomerular leukocyte infiltration in anti-GBM Ab GN. We studied the expression of the C-C (MIP-1a, MCP-1, and RANTES) and C-X-C (PF4, IP-10, MIP-2 and CINC) chemokines 30 minutes, 3, 6, 9, 15 and 24 hrs after induction of heterologous phase anti-GBM Ab GN in Lewis rats. There was a rapid induction of CINC, MIP-2, MCP-1 and MIP-1a mRNAs in the glomeruli of nephritic rats 30 minutes after administration of the anti-GBM Ab, while increases in PF4 and IP-10 mRNAs were not seen until 3 hrs. The mRNA expression of PF4, MIP-1a, MIP-2 and IP-10 peaked at 3 hrs while CINC and MCP-1 peaked at 6 and 15 hrs, respectively. By comparison, the expression of RANTES mRNA in rats with anti-GBM Ab GN did not differ from those of control rats. These changes in chemokine gene expression were asociated with glomerular PMN and monocyte/macrophage infiltration which peaked at 3 (20.8+11.1 PMN/glom) and 24 (8.2+1.0 ED-1 cells/glom) hrs, respectively. The administration of dexamethasone suppressed glomerular chemokine mRNA expression (60-98%) at both 3 and 15 hrs which was associated with a 50-100% reduction in glomerular PMN and monocyte/macrophage infiltration, respectively. In vitro studies on IL-1 stimulated rat peritoneal macrophages demonstrated that glucocorticoids inhibited MCP-1 mRNA expression 86%. Finally, the administration of a neutralizing Ab to CINC decreased glomerular PMN infiltration 41% (11.5+4.9 vs. 19.5+8.9 PMN/glom, P=0.006) at 3 hrs which was associated with a 46% decline in glomerular myeloperoxidase content. These data provide evidence that multiple chemokines may be involved in the recruitment of leukocytes into the glomerulus in anti-GBM Ab GN.

Received 9 November 1994; accepted in final form 8 March 1995.
APS Manuscript Number F401-4.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  2 May 1995.