Inhibition of attachment of human gingival fibroblast-like cells in vitro by saliva and salivary-sulfated glycoprotein in the presence of serum.

We have previously shown that human whole saliva and a high molecular weight sulfated glycoprotein (SGP) salivary component inhibits attachment of human gingival fibroblast-like cells to plastic substrata in serum-free conditions. The purpose of this study was to investigate the influence of saliva on attachment of these cells to tissue culture plastic in the presence of serum. Individual wells of multiwell dishes were coated with either sterile whole saliva or SGP, sequentially with fetal bovine serum followed by saliva or SGP, sequentially with the latter agents applied in the reverse order, with mixtures of saliva and serum or SGP and serum. Washed wells were seeded with 1.0 x 10(5) fibroblasts in alpha-MEM and numbers of adhering cells determined after 30 minutes. Saliva or SGP inhibited cell adherence as previously reported. Cell adherence in wells treated sequentially with saliva or SGP followed by serum, or with the latter followed by the salivary agents, was reduced significantly compared with that in untreated control wells. Wells treated with mixtures of serum and saliva or SGP exhibited progressive reduction in numbers of adhering cells as the concentration of the salivary agents increased. Significant suppression of attachment compared with controls also occurred when cells in alpha-MEM containing 15% serum were plated onto saliva- or SGP-treated wells. These results are consistent with the hypothesis that adsorbed salivary glycoprotein may bring about periodontal wound healing by repair rather than by regeneration by inhibiting fibroblast attachment to root surfaces in vivo.