AIDS vaccine developments.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to R Le Grand.
Explore the source record for details and available documents.
The simian immunodeficiency virus is a retrovirus closely related to the human immunodeficiency viruses; it induces an AIDS-like disease in macaques, and provides therefore an obvious animal model for anti-lentiviral drug and vaccine strategy assessments. In our experiment, we immunized rhesus macaques with a purified and formalin-inactivated whole SIVmac251 antigen preparation. Most of these monkeys were still protected for more than 4 months following a heterologous SIVsm intravenous challenge. Both virus stocks, for vaccine preparation and challenge, were provided by culture supernatants of infected T cells of human origin. Four of the protected macaques were then reimmunized with the same antigen preparation and rechallenged intravenously with a homologous rhesus cell grown SIVmac251. Unexpectedly, all animals developed clinical and biological evidence of infection by day 15 after the second challenge.
Neutralizing and enhancing activities in sera were detected by using an in vitro infection assay of HUT78 cells. Ten animals were vaccinated with HIV-2ROD recombinant vaccinia viruses and respective purified proteins. Only sera from monkeys vaccinated with env elicited neutralizing antibodies. No antibody-dependent enhancement (ADE) properties were detected in all the tested sera. Six other macaques were infected with SIV-mac251. All of them had detectable ADE properties in their sera. No major neutralizing activity was detected.