[Blood plasma fibronectin does not influence fibroblast-induced collagen gel contraction]

Human embryo fibroblasts were cultured within three-dimensional collagen gel in the Eagle medium supplemented with 10% calf serum. Addition of fibronectin (Fn) to the nutrient medium neither stimulated nor inhibited gel contraction by fibroblasts. Gel contraction also proceeded in the medium containing ultroser G or Fn exhausted calf serum. Addition of 10 or 50 micrograms/ml of Fn to the medium with ultroser G exerted no effect on the process of gel contraction. Addition of antibodies prepared against Fn (70 micrograms/ml) and tetrapeptide RGDS (100 and 500 micrograms/ml) to the medium supplemented with Fn exhausted calf serum did not change the rate of collagen gel contraction. The results obtained suggest that the rate of collagen gel contraction by fibroblasts is not dependent on the presence of exogenous fibronectin.