Acridine orange potentiation of actinomycin D uptake and activity

Acridine orange enhances the uptake of [(3)H]actinomycin D in disrupted and intact human lymphocytes, as measured by liquid scintillation and autoradiography. Proflavine, quinacrine, chloroquine, and ethidium bromide are not effective. In mice, acridine orange increases the capacity of actinomycin to reduce spleen weight. Type II acridine binding to DNA may be a prerequisite for actinomycin enhancement.