The effect of the collagen tripeptide fragment (GER) on the adhesion and spreading of fibroblasts depends on the properties of adhesive surface

: The effect of collagen tripeptide fragment GER on the adhesion and spreading of mouse embryonic fibroblasts STO to different substrates--polystyrene plastic and immobilized on plastic poly-L-lysine, fibronectin or gelatin was studied. Tripeptide GER has been found to participate in the regulation of fibroblast adhesion and spreading. Therewith, the tripeptide effect value on cell response was dependent both on the mode of tripeptide addition to culture medium and on the type of used substrate. During coincubation of fibroblasts with the tripeptide the stimulation of cell attachment and spreading to untreated plastic and plastic coated with fibronectin or gelatin was observed. At the same time the tripeptide did not change cell adhesion to immobilized poly-L-lysine. Preincubation of cells with the tripeptide resulted in partial inhibition of fibroblast adhesion and spreading on fibronectin- and gelatin-coated substrata. In was shown that the extent of activation and inhibition of adhesive processes on fibronectin was higher than such ones on gelatin after tripeptide treating. The data obtained support the assumption about concerted action of tripeptide GER (activity of which was dependent both on the used concentration of the tripeptide and on the mode of tripeptide addition to culture medium) and chemical characteristics of substrate (polymers of styrene and L-lysine, ECM proteins in native (fibronectin) or partly denatured (gelatin) form) on the cell adhesion and spreading. The main targets on which the GER peptide may affect during the formation of cell-substrate interactions are discussed.