[Derivation of a mutant (HPRT-) cell line based on K-562 human erythromyeloleukemia]

A mutant (HPRT-) cell line was obtained by a series of passages in the medium with 8-azaguanine on the basis of human erythromyeloleukemia K-562 cells. Rapid total death of the cells in a selective medium containing hypoxanthine, aminopterine and thymidine (3 to 4 passages) supported the deficiency as regards hypoxanthine phosphoribosyltransferase. Preliminary experiments aimed at cytotoxicity studies demonstrated that the new mutant cell line lost the property, common to the parent K-562 line, of being sensitive to the attack of natural killers.