Analysis of marker enzymes in the K562 erythroleukaemia cell line: no coordinate expression of red cell enzymes on induction of haemoglobin synthesis.

Six sublines of the K562 erythroleukaemic cell line were examined by starch gel electrophoresis for the red cell enzymes carbonic anhydrase, CA I and II, pyruvate kinase, PK1 (R), and lactic dehydrogenase, LDH (B), both uninduced and following induction of haemoglobin synthesis with sodium butyrate or haemin. Neither CA or PK1 (R) enzymes were present constitutively found to be inducible characteristics; the LDH isoenzyme pattern showed equal expression of A and B subunits and did not change to the red cell form (B greater than A) on induction. Subline heterogeneity was also examined by analysis of a further 11 polymorphic enzymes, and cell line contamination was found not to account for the previously reported variations in inducibility by sodium butyrate.