Prostaglandin E2, a seminal constituent, facilitates the replication of acquired immune deficiency syndrome virus in vitro.

Acquired immune deficiency syndrome (AIDS)-associated virus is thought to be transmitted effectively through semen during sexual activities from male to male or from male to female. Prostaglandin (PG) E2 is one of the immunosuppressive compounds present in high concentrations in human semen. We, therefore, investigated direct effects of PGE2 and other PGs on AIDS-associated virus infection and replication in vitro. First, type III human T-lymphotropic virus (HTLV-III) was used to infect a T-cell line (MT-4) in culture. PGE2 (10 nM to 10 microM) added to the culture medium enhanced the production of infectious virus in a dose-dependent fashion. In the presence of 5 microM PGE2, 2.5-fold more virus were released from the infected MT-4 cells as compared to untreated control cells on day 3 after infection. Second, when we used an HTLV-III continuous-producer cell line (Molt-4/HTLV-III), PGE2 and PGD2 added to the culture medium increased the number of viruses released from Molt-4/HTLV-III cells. Other PGs such as PGF2 alpha and 13,14-dihydro-15-keto PGE2 did not affect the replication of HTLV-III in this system. These results indicate that some PGs including seminal PGs enhance the AIDS-associated virus replication in vitro. We propose that PGE2 in human semen might directly facilitate the infection of AIDS-associated virus and cause the efficient transmission of the virus during sexual activities.