Changes in quantity of fibronectin from human skin fibroblasts with cellular aging

Using an enzyme-linked immunosorbent assay, we investigated the amount of cell surface fibronectin and the amount released to the culture medium in human skin fibroblasts during successive cultivation. Cell surface fibronectin did not show a remarkable change in quantity through early and midpassage, but it decreased markedly in late passage. Released fibronectin per cell also did not show a remarkable change through early and midpassage. In late passage, however, it exhibited a marked increase.