CD147 renal expression as a biomarker for progressive IgAN

Abstract

BACKGROUND/AIMS: Recent studies have demonstrated that tubulointerstitial injury can predict renal outcomes better than the other histological parameters in patients with IgA nephropathy (IgAN). CD147 is a key regulator of renal tubulointerstitial fibrosis in cellular and animal models. However, it is not clear whether the expression of CD147 correlates with tubulointerstitial injury in IgAN patients. METHODS: We analyzed the degree of CD147 expression and localization in renal biopsy tissues from IgAN patients and correlated their immunostaining scores with clinical and histological parameters. RESULTS: Elevated CD147 expression was found in the basolateral membrane of renal tubules in IgAN patients; however, in normal kidney samples, positive staining for CD147 was not found in the tubular epithelial cells (P = 0.000). CD147 protein expression in the renal tubules showed a negative correlation with estimated glomerular filtration rate (eGFR; r = -0.600, P = 0.000) and a positive correlation with serum creatinine (Scr; r = 0.322, P = 0.002) and tubulointerstitial lesions (r = 0.525, P = 0.000). Moreover, a high level of CD147 correlated with the activation of Slug expression and E-cadherin repression in patients with IgAN. Kaplan-Meier survival curves showed that elevated CD147 expression was associated with decreased renal survival. Multivariate analyses further demonstrated that a high CD147 immunostaining score was an independent predictor of renal outcome in patients with IgAN (HR = 8.731, P = 0.041). CONCLUSION: CD147 expression is associated with tubulointerstitial injury and predicts renal prognosis in IgA nephropathy. CD147 may be an early marker for tubulointerstitial injury IgA nephropathy.