Differential HLA-dependent HIV evolution among subtypes

Retrovirology BioMed Central Open Access Poster presentation Differential HLA-dependent HIV evolution among subtypes DA Dilernia*1, L Lourta2, M Losso3 and H Salomon1 Address: 1National Reference Center for AIDS, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina, 2Hospital Ramos Mejia, Buenos Aires, Argentina and 3Nexo Asociación Civil, Buenos Aires, Argentina * Corresponding author from 2006 International Meeting of The Institute of Human Virology Baltimore, USA. 17–21 November, 2006 Published: 21 December 2006 Retrovirology 2006, 3(Suppl 1):P15 doi:10.1186/1742-4690-3-S1-P15 <supplement> <title> <p>2006 International Meeting of The Institute of Human Virology</p> </title> <note>Meeting abstracts. A single PDF containing all abstracts in this Supplement is available <a href=" http://www.biomedcentral.com/content/files/pdf/1742-4690-3-S1-full.pdf ">here</a></note> <url>http://www.biomedcentral.com/content/pdf/1742-4690-3-S1-info.pdf</url></supplement> © 2006 Dilernia et al; licensee BioMed Central Ltd. Introduction Population HLA-dependent evolution has been documented over the principal HIV proteins. Effect of subtype variability is uncertain. In Argentina, B subtype and recombinant BF variants circulate in equal proportions. types and that variants from subtype B and BF could respond differently to both natural and vaccine-induced immune response. Methods Blood samples were collected from 94 drug-naive HIV infected individuals. DNA and RNA extraction were performed from PBMC and plasma, respectively. HLA-A and B genes were genotyped by PCR-SSOP. Pol and vpu genes were amplified by RT-PCR and sequenced. Aminoacidic positions were codified as 0 = "equal state" (to consensus sequence) and 1 = "variated state" (polymorphism). Phylogenetic analyses were performed by BootScanning. Statistical analysis was performed by ODDS-ratio/power calculations, Fischer exact test, Logistic regression and randomization tests. Potential new epitopes and affinities with HLA were assessed by using BIMAS software. Results We found 95 polymorphisms associated with different HLA alleles. 44 out of them were inside predicted epitopes for the associated HLA allele. 13 out of them reduced the affinity for the HLA allele in the "variated" state. 5 out of them were associated with viral subtype. Conclusion Our results suggest that vpu could be undergoing adaptation to the immune response at the population level, as previously reported for pol gen. Associations with viral subtype suggest that this evolution is different among sub- Page 1 of 1 (page number not for citation purposes)