Expression of heat-shock protein 47 in mouse liver

Expression of heat-shock protein 47 in intact and fibrotic liver and in hepatic constituent cells was investigated in mice. Immunohistochemical study of intact liver and Western blot analysis of the protein from isolated liver cells revealed that stellate cells and smooth muscle cells of interlobular vessels, but not hepatocytes, Kupffer cells, or endothelial cells, expressed heat-shock protein 47. The protein was found in both vitamin-A-storing stellate cells and myofibroblast-like cells. The amount of the protein in cultured stellate cells was reduced by dexamethasone but was not regulated by quercetin, transforming growth factor beta, interferon gamma, or retinoic acid. In CCl4-treated or bile-duct-ligated mouse liver, the number of cells positive for heat-shock protein 47 markedly increased in the centrilobular area or around the periportal area, respectively, and the level of heat-shock protein 47 also increased.