POTENTIAL IMMUNE-BASED INTERVENTIONS TO REDUCE HIV-1 VERTICAL TRANSMISSION

Abstract

This article reviews the historical basis, current research models, and possible future directions of transplacental immune-based prophylaxis of transmission of HIV-1 from mother to child. By taking advantage of transplacental passage of immunoglobulin G (IgG) molecules or derivatives, it may be possible to provide protection against HIV-1 vertical transmission, in addition to that provided by maternal and neonatal antiretroviral chemoprophylaxis with zidovudine (ZDV).10 Because antiretroviral drugs are unlikely to be able to completely eradicate HIV-1 infection from an already infected host, it seems inescapable that some form of immunotherapy must be given to either eradicate infection or to restore the immune system.47 A transplacental approach could be used to provide immune-based prophylaxis, either passive or active immunization. Passive immunoprophylaxis would include giving mothers HIV-specific IgG antibodies or derivatives, and active immunoprophylaxis would include giving mothers HIV-1 vaccines, to which they would generate HIV-specific IgG antibodies. In both cases, transplacental passage of these substances might either prevent the fetus or neonate from acquiring HIV-1 infection altogether or facilitate the eradication of HIV-1 from the infant. In addition, in those infants who become infected despite prophylaxis, provision of in utero immunotherapy might prove beneficial in reconstituting the humoral and cellular immune system in combination with antiretroviral therapy after birth.