Abstract: Objective To investigate whether calcineurin is upregulated along with podocytes injury in anti-glomerular basement membrane (GBM) disease, and the relationship with the clinicopathological characters and the kidney survival. Methods The expression of α isoform of calcineurin A subunit (CnAα) and synaptopodin was detected by immunohistochemistry and immunofluorescence, respectively, in renal biopsy tissues from 29 patients with anti-GBM disease compared with 8 cases with glomerular minimal lesion as control. And we analyzed the relationship between CnAα expression and the clinicopathological manifestations and outcome of anti GBM disease. Results CnAαwas upregulated in all anti-GBM disease patients, with the positive area significantly larger than that of glomerular minimal lesion (21.63%±14.27% vs 2.21%±1.41%，p<0.01). The expression of CnAα, with loss of synaptopodin, correlated well with anti-GBM antibody titer, SCr, HGB, crescents, cellular/fibrocellular crescent proportion and the renal outcome. Conclusion It was found for the first time that the overexpression of CnAα showed good correlation with anti-GBM disease activity, severity and prognosis, which may indicate that podocyte injury take part in crescents formation. The mechanism involved requires further research.

Key words: anti-glomerular basement membrane disease, calcineurin, podocyte