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Showing papers on "SAIDS Vaccines published in 1995"


Journal ArticleDOI
24 Mar 1995-Science
TL;DR: Adult macaques do not develop disease after infection with a nef deletion mutant of the simian immunodeficiency virus (SIV) and are protected against challenge with pathogenic virus, but neonatal macaques developed persistently high levels of viremia after oral exposure to SIV nef, vpr, and negative regulatory element (NRE) deletion mutant.
Abstract: Adult macaques do not develop disease after infection with a nef deletion mutant of the simian immunodeficiency virus (SIV) and are protected against challenge with pathogenic virus. This finding led to the proposal to use nef-deleted viruses as live, attenuated vaccines to prevent human acquired immunodeficiency syndrome (AIDS). In contrast, neonatal macaques developed persistently high levels of viremia after oral exposure to and SIV nef, vpr, and negative regulatory element (NRE) deletion mutant. Severe hemolytic anemia, thrombocytopenia, and CD4+ T cell depletion were observed, indicating that neither nef nor vpr determine pathogenicity in neonates. Because such constructs have retained their pathogenic potential, they should not be used as candidate live, attenuated virus vaccines against human AIDS.

512 citations


Journal ArticleDOI
TL;DR: Findings show that live-attenuated vaccine can confer protection against SIV in macaques, and the mechanism of this potent protection must be understood and reproduced by less hazardous means.

235 citations


Journal ArticleDOI
TL;DR: Three of the four monkeys infected for greater than 600 days with a chimeric virus composed of SIVmac 239 expressing the human immunodeficiency virus type 1 HXBc2 env, tat, and rev genes were challenged intravenously with 100 animal infectious doses of the J5 clone of Sivmac 32H, an isolate derived by in vivo passage of Siva 251.
Abstract: Prior infection with a nef-deleted simian immunodeficiency virus (SIV) protects macaques not only against a homologous pathogenic SIV challenge but also against challenge with a chimeric SIV expressing a human immunodeficiency virus type 1 env gene (SHIV). Since this SHIV is itself nonpathogenic, we sought to explore the use of a nonpathogenic SHIV as a live, attenuated AIDS virus vaccine. Four cynomolgus monkeys infected for greater than 600 days with a chimeric virus composed of SIVmac 239 expressing the human immunodeficiency virus type 1 HXBc2 env, tat, and rev genes were challenged intravenously with 100 animal infectious doses of the J5 clone of SIVmac 32H, an isolate derived by in vivo passage of SIVmac 251. Three of the four monkeys became infected with SIVmac. This observation underlines the difficulty, even with a live virus vaccine, in protecting against an AIDS virus infection.

28 citations