Differential expression of various cytokine and chemokine genes between proliferative and non-proliferative glomerulonephritides.

BACKGROUND: Intraglomerular cellular proliferation is one of the major determinants for dividing various glomerulonephritis (GN) into two groups, such as proliferative versus non-proliferative. Cytokines and chemokines are involved in the pathogenetic pathways and would affect the functional and histologic sequelae. We hypothesized that the morphological difference might be based on the differential intrarenal expression of various cytokines and chemokines. We quantified the intrarenal gene expression of various cytokines and chemokines, and correlated it with clinical parameters. METHODS: Total RNA was extracted from 54 proliferative GN (PGN) core biopsy specimens and 42 non-proliferative GN (NPGN) specimens. Using the internal competitors, RT-PCR was instituted to quantify mRNAs. RESULTS: The magnitude of the gene expressions of IL-2, IFN-gamma, and IFN-gamma/IL-10 ratio were significantly higher in PGN than in NPGN. RANTES and IL-8 had more abundant gene messages in PGN. It was shown that Th1 cytokine was upregulated if GN was mediated by immune complexes regardless of cellular proliferation. But chemokines had the elevated levels of expression in PGN among immune complex-mediated GN. Up-regulation of the IFN-gamma/IL-10 ratio and TNF-alpha was associated with poor renal function at the time of biopsy. Renal tissues from the patients with a non-nephrotic range of proteinuria showed abundant messages for proinflammatory cytokines and chemokines. CONCLUSION: Th1, proinflammatory cytokines, and chemokines were more abundant in proliferative GN, and correlated with unfavorable clinical parameters. We propose that the clinical manifestations and diverse histologic features of human GN are associated with differential expressions of specific cytokines and chemokines.