title: In vitro growth and differentiation of human kidney tubular cells on a basement membrane substrate.
abstract: Kidney cortical tubular cells, mainly proximal tubular cells, isolated from human kidney and grown either on a basement membrane substrate in chemically defined medium or on plastic in serum-supplemented medium, had substantial proliferative potential and could be propagated for more than 10 generations or 8 passages before senescence. Basement membrane produced on a plastic substrate by the HR-9 endodermal cell line could replace serum supplementation in promoting tubular cell growth. Tubular cells grown on an HR-9 basement membrane substrate exhibited stable epithelial morphology over an extended period of time; in the presence of 5% serum they differentiated into organized structures such as hemicysts and cell cords. Cells grown on plastic failed to differentiate and gradually degenerated. Tubular cells on HR-9 basement membrane were characterized by densely packed microvilli, abundant rough endoplasmic reticulum and free polysomes, basal cell membrane interdigitations, a well-developed endocytotic apparatus, and conspicuous junctional complexes--all features of the proximal tubular cell. Compared with cells on plastic substrate, there were higher levels of the brush border enzymes gamma-glutamyl transpeptidase, L-leucine aminopeptidase, and alkaline phosphatase in cells maintained on an HR-9 basement membrane substrate, further supporting the conclusion that a basement membrane substrate promoted differentiation of tubular cells. These data and morphological observations indicate that a basement membrane substrate can promote growth and both functional and morphologic differentiation of human kidney tubular cells.
mesh_terms: D001485:Basement Membrane / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D046508:Culture Techniques / Q000379:methods; D006801:Humans; D007684:Kidney Tubules / Q000166:cytology*; D008871:Microvilli / Q000201:enzymology; D010969:Plastics
chemical_list: D003470:Culture Media; D010969:Plastics