Studies on HIV epitopes as candidates for drug and vaccine development

Acquired Immune Deficiency Syndrome (AIDS) is the leading cause of death in humans in the age group 25 to 44.

The causative agent of AIDS is the HI virus, which is a retrovirus consisting of two types – the more pathogenic and widespread HIV-1, and HIV-2, which occurs mainly in West Africa.

According to estimates by the Joint United Nations Programme on AIDS, HIV continues to spread globally and has now been reported in every country in the world. It is estimated that there are 16,000 new HIV-1 infections daily, and 90% of those occur in developing countries. Sub-Saharan Africa had an estimated 22.5 million HIV infected people in 1999. Predicted are that this disease will have a major impact on the economies of developing countries.

The development of an effective treatment regime and a vaccine has been hindered by the extensive variability of the virus. It is this genetic diversity that forms the basis of the subtyping of the virus. Of note is that the strains occurring in the USA and Europe are primarily of subtype A and B, and those of sub-Saharan Africa are mainly of subtype C.

Vaccines developed to date have mainly focused on subtypes A and B, as the majority of work has been carried out in the USA and Europe. Little to no work has been carried out on vaccine development for subtype C, as this is largely a Third World problem. It is believed that any vaccine developed against subtypes A and B would not be effective against subtype C, thereby necessitating the independent development of vaccines for subtype C.

The current project makes use of protein homology modelling, testing of peptide inhibitors, NMR structural analysis, phage display, and a number of other techniques for the development of novel vaccine candidates.

For more information, contact:
Dr Colin Kenyon, Tel: +27 11 605 2702, Fax: +27 11 608 3020