title: HeLa cell adhesion to microcarriers in high shear conditions: evidence for membrane receptors for collagen but not laminin or fibronectin.
abstract: HeLa-S3 cells were analyzed for their ability to attach and spread on cell culture microcarriers that were made either positively or negatively charged with polymeric plastics or were coated with BSA, gelatin, fibronectin or laminin. The cells stuck to all microcarriers under low shear, i.e. low stirring conditions with similar rates of attachment. Except in the case of gelatin microcarriers where cells fully spread, cells did not or only partially spread on the others. Under high shear, cells attached with the following rates: positive = negative = gelatin = BSA greater than laminin greater than fibronectin. Cells detached from all but the gelatin and BSA coated beads. However, the cells did not fully spread on BSA beads. The observation that cells not only attached but also spread on gelatin beads indicated that gelatin could be a specific substratum adhesion protein while the other surfaces were 'non-specific'. It should be noted that neither antibodies to laminin nor fibronectin interfered with attachment to gelatin. Protein synthesis inhibitors reduced the attachment and spreading on gelatin beads under high but not low shear conditions. With low shear, attachment and spreading appeared normal. We concluded that the density of the cell surface attachment proteins was reduced by the protein synthesis inhibitors and there were not enough present to facilitate attachment under high shear. The results also indicated that protein synthesis was not essential for cell spreading. Proteolysis of the cell surface with low concentrations of trypsin abolished the attachment of cells to gelatin-coated beads. The reappearance of attachment ability took several hours and was inhibited by actinomycin-D.
mesh_terms: D002448:Cell Adhesion; D002462:Cell Membrane / Q000378:metabolism; D003094:Collagen / Q000378:metabolism*; D006367:HeLa Cells / Q000378:metabolism*; D006801:Humans; D008863:Microspheres; D014176:Protein Biosynthesis; D011956:Receptors, Cell Surface / Q000378:metabolism*; D038981:Receptors, Collagen; D017469:Receptors, Fibronectin; D017474:Receptors, Laminin; D014357:Trypsin / Q000494:pharmacology
chemical_list: D011956:Receptors, Cell Surface; D038981:Receptors, Collagen; D017469:Receptors, Fibronectin; D017474:Receptors, Laminin; D003094:Collagen; D014357:Trypsin