COMPLEMENT-DEPENDENT INDUCTION OF DNA-SYNTHESIS AND CELL-PROLIFERATION IN HUMAN LIVER CONNECTIVE-TISSUE CELLS IN-VITRO

Liver connective tissue cells (LCTC) isolated from patients with fibro tic livers have morphological and biochemical characteristics of myofi broblasts. We have examined the proliferation of LCTC derived from nor mal livers and from livers with fibrosis of different etiologies, as w ell as proliferation of skin fibroblasts. We have compared proliferati on rates in the presence of fresh human serum and heat-inactivated ser um. While skin fibroblast and LCTC from normal liver showed no differe nce, proliferation of LCTC from fibrotic livers was markedly decreased in the presence of heat-inactivated serum. We demonstrate that the na tive complement component Cl is a factor involved in the induction of DNA synthesis and proliferation of LCTC isolated from fibrotic livers. We propose that native Cl, acting probably in cooperation with other growth factors, is involved in the expansion of connective tissue cell s during the development of liver fibrosis.