Mapping HIV-1 Subtype C gp120 Epitopes Using a Bioinformatic Approach

摘要

Human Immunodeficiency Type-1 subtype C (HIV-IC) is rapidly diverging among populations causing more than 48% of infections worldwide. HIV-IC gp120's 128 sequences available at Genbank were aligned and submitted to phylogenetic analysis. Three major clusters were identified: 72 sequences aligned with a Brazilian 0072eference sequence; 44 sequences aligned with an Ethiopian sequence and 12 could be group along with Indian isolates. A search was made for conserved HIV-IC cytotoxic T lymphocyte (CTL) epitopes to A*0201, A*0301, A*1101 e B*07 human leukocyte antigen (HLA) alleles (using Epijen software). Five most conserved epitopes were recognized: QMHEDIISL, CTHGIKPVV, NLTNNVKTI, AITQACPKV, CTRPNNNTR. Our results showed a recognized evolutionary force of HIV-1 to escape from CTL responses mutating sites that can be negatively select by host's immune system. The present study brings up a new approach to in silico epitope analysis taking into account geographical informations on virus diversity and host genetic background.