Variations in drug sensitivity among five mammalian cell lines used in an agar plate assay.

The drug sensitivity of four human cell lines was compared with that of Sarcoma 180 (of mouse origin) in an agar plate assay procedure. Significant differences in cell line response were found with actidione, methotrexate, puromycin aminonucleoside, strophanthin K, mitomycin C, and streptovitacin A. They ranged from 31-fold with mitomycin C to 8,500-fold with strophanthin K. The significance of the differences demonstrated in agar plates was discussed with particular reference to cell line selection for the assay of a specific drug by the agar plate technic and the value of cell line response pattern as a tool in drug identification.