Characteristics of REPCs. (A) Morphology of REPCs at days 1 and 7 in culture. Shown are representative microscopic images at a final magnification of 400×. (B) Expression of kidney fibroblast–specific markers on REPCs compared with human kidney tissue. The EMT marker FSP-1 was not expressed in REPCs. Shown are representative agarose gels stained with ethidium bromide. (C) Differential expression of epithelial and neuronal markers on REPC and HK2 cells. REPCs were negative for the epithelial marker N-cadherin and lectin staining, but positive for MAP-2, NF-L, and CD73. (D) Proliferation of REPCs under normoxic and hypoxic conditions. REPCs were cultured for up to 7 days under normoxic and hypoxic conditions. Cells were counted every day, and cell proliferation was not influenced by hypoxia. Shown are the means ± SD; n = 6.