Application of the enzyme histochemical method for the isolation of HeLa variant inducibly producing the Kasahara isozyme of alkaline phosphatase.

A cloning method utilizing the enzyme histochemical procedure was applied to isolate variant HeLa subclones which produce different alkaline phosphatase isozymes. Phosphate was used to distinguish between Kasahara isozyme and Regan isozyme. The use of filter paper made it possible to determine the localization of the Kasahara isozyme-positive colonies. By this method, two variant clones, HeLa S3-10 KP and HeLa S3-10 KN, were isolated. Kasahara isozyme was induced in the former by increased cell density, but not in the latter.