Transformation-induced alterations in fibroblast adhesion: masking by trypsin treatment.

As assessed by initial rates of cell aggregation, adhesivity of EDTA-suspended cells is increased by SV 40 transformation of mouse 3T3 and human WI 38 fibroblasts. Preparation of cell suspensions by trypsin treatment decreases the aggregation rate and abolishes the difference between transformed and untransformed cells. These findings suggest that increased cellular adhesivity accompanies the surface alterations induced by viral transformation and that trypsinization masks these changes. Thus, use of freshly trypsinized cells in quantitative assessments of cellular adhesivity may yield results which do not reflect the actual cell properties.