* To provide a surveillance system for newly emerging and naturally occurring recombinant HIV-1 strains in Cameroon and Gabon.
* To classify sera from HIV infected individuals according to their capacity to neutralise primary isolates representing different genetic clades.
* To characterize broadly neutralising antibodies and epitopes in individuals infected with HIV-1 of different genetic subtypes, and evaluate the role they play in disease protection.
* To investigate the susceptibility of HIV-1 strains belonging to different genetic clades, to both existing and experimental anti-HIV compounds and to provide a surveillance system for emerging strains of HIV-1 with naturally occurring mutations conferring antiviral drug resistance.
* To optimize the quantification of HIV RNA in plasma of patients infected with different types, subtypes and recombinant subtypes of HIV.
Making available to developing countries a simple economical serologic test to monitor circulating HIV-1 subtypes.
The study design will be as follows: both heteroduplex mobility assay (HMA) on PCR amplified fragments generated from HIV RNA in serum or plasma of HIV infected individuals and V3-peptide ELISA will be used to monitor the prevalence of different genetic subtypes of HIV-1. HMA on both gag and env fragments of the same isolate will allow to study the prevalence of recombinant viruses. Susceptibility of the different subtypes and the natural recombinant viruses towards various HIV inhibitors will be determined. Neutralizing antibody patterns in sera of individuals infected with all subtypes (A-H) within group M and representatives of group O to their homologous and heterologous primary isolates will be documented using a peripheral blood mononuclear cell based neutralisation assay. Neutralisation data will be analyzed by a multivariate (spectral mapping) analysis. Chimeric viruses consisting of neutralisation sensitive and insensitive primary HIV-1 strains will be constructed in order to characterize the epitopes playing a role in the neutralisation process. Human monoclonal antibodies with cross-clade neutralisation capacity will be generated.
Consecutive isolates and sera of long term, slow and rapid progressors will be analyzed in a time paired sequential manner in autologous and heterologous neutralisation experiments, in order to monitor the role of neutralisation antibodies in the progression of the infection.
Funding SchemeCSC - Cost-sharing contracts