Expression of response gene to complement-32 in renal tissue of children with immunoglobulin A nephropathy

Abstract

Objective. This study aimed to investigate the expression and significance of response gene to complement-32 (RGC-32) in renal tissue of children with immunoglobulin A nephropathy (IgAN). Material and methods. Forty-five patients diagnosed as having IgAN by renal biopsy were enrolled. The expression of RGC-32, α-smooth muscle actin (α-SMA) and transforming growth factor-β₁ (TGF-β₁) was observed by immunohistostaining. The relationshis between the expression of RGC-32, α-SMA, TGF-β1, degree of renal pathological lesions in IgAN and clinical index were assessed by Spearman correlation. Results. Immunohistostaining analysis showed that RGC-32 protein was present in epithelial cells of renal tubules in normal and IgAN renal tissues. With more severe renal pathological lesions, the expression of RGC-32 in IgAN was increased. The expression of RGC-32 was positively correlated with that of α-SMA, TGF-β₁ and the degree of renal pathological lesions in children with IgAN (p < 0.05), but had no relationship with serum creatinine, urinary N-acetyl-β-d-glucosaminidase/creatinine, urinary microalbuminuria/creatinine, urinary microimmunoglobulin/creatinine or urinary α₁-microglobulin/creatinine ratio (p > 0.05). Conclusion. Expression of RGC-32 can reflect the degree of renal pathological lesions in IgAN. RGC-32 may participate in the renal tubulointerstitial lesions in children with IgAN, especially in epithelial –mesenchymal transition induced by TGF-β₁.

Key Words::

• epithelial –mesenchymal transition
• IgA nephropathy
• RGC-32
• renal tubulointerstitial fibrosis

Acknowledgements

We appreciate Professor Shi-You Chen, Georgia University, offering the polyclonal antibody anti-human RGC-32, and also a Chinese National Natural Science Foundation Grant. This work was supported by Chinese National Natural Science Foundation Grant 30871177, and was conducted in Department of Pathology, Shanghai Medical College, Fudan University, China.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.