Resistance-associated epitopes of HIV-1C - Highly probable candidates for a multi-epitope vaccine

Abstract

Earlier studies have identified a large number of immunogenic epitopes in HIV-1. Efforts are required to prioritize these epitopes in order to identify the best candidates for formulating an effective multi-epitope vaccine for HIV. We modeled 155 known cytotoxic T lymphocyte epit-opes of HIV-1 subtype C on the 3D structure of HLA-A *0201, HLA-B *2705, and HLA-B *5101 using MOD-PROPEP, as these alleles are known to be associated with resistance to HIV/slow progression to AIDS. Thirty-six epitopes were identified to bind to all the three HLA alleles with better binding affinity than the control peptides com-plexed with each HLA allele but not to any of the HLA alleles reported to be associated with susceptibility to HIV infection/rapid progression to disease. As increase in stability of the epitope-HLA complex results in increased immu-nogenicity, the short-listed epitopes could be suitable candidates for vaccine development. Twenty of the 36 epit-opes were polyfunctional in nature adding to their immuno-logical relevance for vaccine design. Further, 9 of the 20 polyfunctional epitopes were found to bind to all three resistance-associated HLA alleles using an additional method, adding worth to their potential as candidates for a vaccine formulation for HIV-1C. © Springer-Verlag 2012.