Differentiated properties characteristic of renal proximal epithelium in a cell line derived from a normal monkey...

The JTC-12 cell, an established cell line derived from a normal monkey kidney, was studied in an attempt to characterize the epithelial qualities. Phase contrast microscopy showed dome formation in confluent monolayers and electron microscopic examinations revealed the presence of numerous microvilli on the apical membranes and desmosome between cells. Sonicated cells showed activities of gamma-glutamyl transpeptidase, leucine aminopeptidase, alkaline phosphatase, and trehalase, marker enzymes of renal proximal epithelium. Alkaline phosphatase activity exhibited the characteristics of a renal type isozyme. Furthermore, confluent JTC-12 monolayers exhibited Na+-dependent transport of hexose, amino acid as well as inorganic phosphate. These findings indicate that JTC-12 cells in monolayer culture maintain ultrastructural, biochemical, and physiological properties of renal proximal epithelial cells. This cell line will be useful for further studies on cellular functions of renal proximal epithelium.