Binding of hyaluronate to the surface of cultured cells.

Abstract

The binding of hyaluronate to SV-3T3 [SV-40-transformed mouse fibroblast 3T3 cells] cells was measured by incubating a suspension of cell (released from the substratum with EDTA) with 3H-hyaluronate and applying the suspension of glass fiber filters which retained the cells and the bound hyaluronate. The extent of binding was a function of the concentration of labeled hyaluronate and the cell number. Most binding took place within the first 2 min of incubation and was not influenced by the presence or absence of divalent cations. The binding of labeled hyaluronate to SV-3T3 cells was prevented by addition of excess unlabeled hyaluronate. High MW preparations of hyaluronate were more effective in preventing binding than low MW preparations. The binding of [3H]hyaluronate was inhibited by high concentrations of oligosaccharide fragments of hyaluronate consisting of 6 sugars or more and by chondroitin. The sulfated glycosaminoglycans (chondroitin-4-sulfate, chondrotin-6-sulfate, dermatan sulfate, heparin and heparan sulfate) had little or no effect on the binding. The labeled hyaluronate bound to the cells was totally removed by incubating the cells with testicular hyaluronidase, Streptomyces hyaluronidase or trypsin, indicating that the hyaluronate-binding site are located on the cell surface.