Polarized M2c macrophages have a promoting effect on the epithelial-to-mesenchymal transition of human renal tubular epithelial cells.

This study planned to explore the effects of M2c macrophages on epithelial-to-mesenchymal transition (EMT) of human renal proximal tubular epithelial cells (HK-2). Human monocytic leukaemia cells were induced by TPA and IL-10 to differentiate M2c macrophages. Subsequently HK-2 cells were co-cultured with the M2c macrophages in Transwell chamber. After 48 h of co-culturing the HK-2 cells were detected in the mRNA and protein expression of E-cadherin, α-SMA and vimentin with RT-PCR, immunofluorescence and Western blot respectively. Besides, the migration ability of the HK-2 cells was estimated with Transwell migration assay. ANOVA was used to compare the difference between groups and Student's t-test to conduct multiple comparisons of two groups. P < 0.05 was considered statistically significant. The results showed that the mRNA and protein expression of α-SMA and vimentin of the HK-2 cells were increased but the E-cadherin decreased significantly after 48 h co-culturing with the M2c macrophages (P < 0.05 or P < 0.01). And the migration ability of HK-2 cells were also increased significantly (P < 0.05). It may be concluded that polarized M2c macrophages may have a promoting effect on the EMT of HK-2 cells.