Inhibition of human immunodeficiency virus type 1 replication by nonionic block polymer surfactants

Eight block copolymers of hydrophilic polyoxyethylene and hydrophobic polyoxypropylene were examined for their effects on the replication of human immunodeficiency virus type 1 (HIV-1) in H9 cells. Although the polymers decreased cellular replication, they did not appear to be toxic to the cells; rather, they seemed to arrest cellular growth. Three triblock copolymers were found to inhibit HIV replication at low concentrations. Maximum inhibition was achieved at concentrations of 50 micrograms/ml by day 5 following infection. The combination of azidothymidine with both HIV-1-inhibitory and noninhibitory copolymers resulted in antagonistic effects, with an increase in viral replication, compared to treatment with copolymers or azidothymidine alone. These copolymers should be useful in the study of the mechanism of HIV replication in cell cultures and may yield clinically useful compounds in combination therapies for HIV infection.