title: Sulphonated polystyrene as an optimal substratum for the adhesion and spreading of mesenchymal cells in monovalent and divalent saline solutions.
abstract: Cell adhesion and spreading were studied on sulphonated polystyrene dishes in serum-free saline (Mn, Na, Cl, buffer) i.e., without an intervening protein layer. Spreading as a function of surface charge density, SCD, peaked around 2-10 negative charges per square nanometer, corresponding to a monomolecular layer of sulphonate ions. At optimal SCD, macrophages, BHK-C13 and whole mouse embryo secondary cells all showed considerable spreading, even in monovalent saline-more so than on a conventional tissue-culture surface. But outside this narrow range of SCD, or on protein-coated surfaces, the divalent cation was indispensable. The biphasic effect of sulphonation on cell adhesion is consistent with the theory that a substratum need not be biochemically specific, provided it is physiochemically polar, rigid and dense. According to this theory, polystyrene of sub-optimal SCD would not be sufficiently polar, while supra-optimal sulphonation would produce a hydrogel surface, lacking in local rigidity and density, due to osmotic swelling. The principle of polymer exclusion, by a surface hydrogel layer, is also consistent with observations on the inhibitory effects of adsorbed proteins-viz., albumin, collagen, serum and cellular exudate, respectively-contrasted with the ready attachment of cells to a bare, optimally charged substratum, in this minimal in vitro system.
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D001639:Bicarbonates; D002448:Cell Adhesion / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D002746:Chlorpromazine / Q000494:pharmacology; D006224:Cricetinae; D003470:Culture Media; D003911:Dextrans / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D008264:Macrophages / Q000502:physiology; D008345:Manganese; D051379:Mice; D011137:Polystyrenes; D011188:Potassium; D012965:Sodium Chloride; D013451:Sulfonic Acids; D013499:Surface Properties
chemical_list: D001639:Bicarbonates; D003470:Culture Media; D003911:Dextrans; D011137:Polystyrenes; D013451:Sulfonic Acids; D008345:Manganese; D012965:Sodium Chloride; D004492:Edetic Acid; D011188:Potassium; D002746:Chlorpromazine