Sensitivity of transformed and nontransformed cells to amphotericin B and several rifamycin derivatives.

SUMMARY Probable synergy has been demonstrated for the com binations of amphotercin B and each of several nifamycin Sv derivatives against nontransformed BALB/3T3 cells and cells transformed with munine sarcoma virus. Synergy also appeared to be present for the combinations of am photericin B and dimethyl formamide on ethanol. The transformed cells were more sensitive to the com binations than nontransfonmed cells, but this was depend ent on a selective toxicity of the amphotenicin B and not the rifamycins.