western blotting analysis and monoclonal antibodies to individual cytokeratins revealed that untreated k562 cells expressed mr 52,000 ( no . 8 ) , 46,000 ( no . 18 ) , and 40,000 ( no . 19 ) cytokeratin polypeptides , which disappeared when the cells were exposed to hemin or to sodium butyrate to induce erythroid differentiation but were greatly enhanced when exposed to tpa .
C0007634
cells
C0007589
differentiation