Collagen-induced alterations in intercellular adhesion and antigen expression in retinoblastoma cells

Y79 human retinoblastoma cells, which typically grow as suspension cultures in vitro, show increased intercellular and cell-substratum adhesion, and form compact cellular aggregates when cultured on a collagen substratum. Concomitant with collagen-induced formation of compact cellular aggregates, is an increase in the binding of peanut lectin, especially at points of intercellular apposition. In addition, increases in the binding of antibodies against neuron-specific enolase and the cone-specific monoclonal antibody CSA-1 are noted following attachment and growth on collagen. In contrast, a decrease in the binding of antibodies against the glial marker, glial fibrillary acidic protein, is observed in collagen-attached cells. Thus, both the adhesive properties and the biochemical composition of Y79 retinoblastoma cells are altered by their attachment to and growth upon a collagenous substratum.