Human serum albumin stimulates osteopontin and CD44 expression in human renal proximal tubular epithelial cells / 中国病理生理杂志

ABSTRACT

AIM: To investigate the expression of osteopontin (OPN) and CD44 in human renal proximal tubular epithelial cells stimulated by human serum albumin (HSA). METHODS: Proximal tubular epithelial HK-2 cells were stimulated by HSA at different concentrations for different time, then OPN mRNA production was detected by RT-PCR, and OPN protein was detected by Western blotting. The expression of OPN and CD44 in HK-2 cells after stimulation for 24 h or 48 h were detected by immunofluorescence with confocal laser scanning microscope. RESULTS: Osteopontin mRNA in HK-2 cells showed a highest expression at 3 h and 48 h after HSA stimulation. However, the expression of OPN protein in HK-2 cells reached the maximum at 24 h after HSA stimulation. OPN mRNA and protein showed a strong dose-dependence relation with the concentration of HSA. HSA also stimulated HK-2 cells to express CD44 protein, the fluorescence of CD44 was most prominent at 48 h after HSA stimulation. CONCLUSION: HSA stimulates human renal proximal tubular epithelial cells to express OPN and CD44.