The Interaction Between Macrophages And Cyst-lining Epithelial Cells And Its Mechanism In Polycystic Kidney Disease

Objective:This study was to explore the mechanism of the macrophages’ polarization and tubule cells proliferation in mocro-environment which is composed of OX161 cyst-lining epithelial cell,UCL93 renal epithelial cells and RAW264.7 microphages during the process of autosomal dominant polycystic kidney disease(ADPKD).Methods:1.Confirm the relationship between the process of ADPKD and the level of L-Lactic acid in kidney tissure of Pkd1 induced knockout mice.2.To confirm the association between the level of L-Lactic acid and cystic index in Pkd1 induced knockout mice.3.To test the expression of L-Lactic acid and MCP-1 in the conditional medium of OX161 and UCL93.4.To study whether L-Lactic acid triggers RAW264.7 mouse macrophages phenotype differentiation.RT-PCR、Western blot and Laser confocal imaging were used to analyze the expression of ARG1.5.To test whether ARG1 can be released out of the RAW264.7 cell,we collected the conditional medium of RAW264.7 cell which stimulated by L-Lactic acid before,enzyme-linked immunosorbent assay were used to analyzed the ARG1 expression in the conditional medium.6.To test whether the activity of ARG1 in RAW264.7 cell is high after treated by L-lactic acid,we collected RAW264.7 cell and text the activity of ARG1 in RAW264.7 cell.7.RAW264.7 cell was transwell co-cultured with OX161 or UCL93.EdU was used to detect the proliferation of OX161 and UCL93,Flow cytometry was preformed to test the periodic change.And then,Arginine inhibitor—Nω-hydroxy-Nor-L-arginine(Nor-NOHA)was added into the medium of co-culture system.The same metheds were performed to analyse the proliferation condition and the periodic change.8.We added ARG1 and Nor-NOHA into the condition medium of OX161,EdU was used to detect the proliferation of OX161,Flow cytometry was preformed to test the Periodic change,Western blot was used to analyse P-ERK protern.Results:1.Cystic index and L-Lactic acid were up-regulated in kidney disease with the prosess of ADPKD which was induced by Pkd1 induced knockout mice.2.OX161 cyst-lining epithelial cell and UCL93 renal epithelial cell secrete MCP-1 which can induce microphages around the cyst.L-Lactic acid was secreted by OX161 and UCL93,promotes macrophages differentiation and express ARG1.3.ARG1 could be secreted as a soluble factor and is a strong pro-proliferative molecule,which can promote the proliferation of cysts and the progression of ADPKD.Conclusion:In this experiment we find that OX161 and UCL93 cell both can secrete MCP-1,which induce microphages around the cyst.L-Lactic acid as a strong factor to stimulate macrophages differentiation and express ARG1,ARG1 serves as a strong pro-proliferative molecule,and reveals its possible mechanism.The interaction between microphages and renal epithelial cells lead to the progression of ADPKD.In general,this study might provide a new methed and strategy to prevent the progression of the disease and potential therapeutic target for ADPKD.