Biological and biochemical criteria for the characterization of the transformed stage of BHK21 cells.

Some quantitative criteria for spontaneous and virus-induced transformation of BHK21 cells are described. The resistance to acid polysaccharides such as dextran sulphate in agarose medium is a characteristic shared by all tumorigenic clones. The increase in a high molecular weight integral membrane protein seems to be a biochemical feature correlated with this property.