8-Azaguanine resistant African green monkey kidney cell mutants (Vero 153): isolation and characterization

A clone of Vero cells resistant to up to 20 micrograms/ml 8-azaguanine was isolated. This clone (designated Vero 153) has a doubling rate of approximately 24 h and a maximum cell density of 10,000/mm2. Deficiency of the enzyme hypoxanthine guanine phosphoribosyl transferase (HGPRT) in Vero 153 was demonstrated by methods of radiochromatography. Vero 153 is susceptible to hypoxanthine-thymidine-aminopterin (HAT) medium and its resistance to 8-azaguanine seems to be nonreversible. Like parental cells, Vero 153 was also incapable of interferon production when challenged with Newcastle disease virus (NDV) or poly(inosinic acid) . poly(cytidylic acid) (poly I:C). Similar chromosome complements (majority range 56 to 57) and band patterns were observed in cells harvested at Passages 10, 20, and 50. The potential use of Vero 153 for somatic cell hybridization for purposes of gene mapping, virus rescue, and the control of interferon production is discussed.