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Biomedical subjects

R Le Grand

Publications and source records attributed to R Le Grand.

3 recordsLinked to original sources

Specific and non-specific immunity and protection of macaques against SIV infection.

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.

Animals

Antibody-dependent enhancement and neutralization pattern of sera from SIV-infected or HIV-2-vaccinated rhesus monkeys.

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.

AIDS Vaccines