Influence of HAART on alternative reading frame immune responses over the course of HIV-1 infection.

Autor: Champiat S; Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America., Raposo RA, Maness NJ, Lehman JL, Purtell SE, Hasenkrug AM, Miller JC, Dean H, Koff WC, Hong MA, Martin JN, Deeks SG, Spotts GE, Pilcher CD, Hecht FM, Kallas EG, Garrison KE, Nixon DF
Jazyk: angličtina
Zdroj: PloS one [PLoS One] 2012; Vol. 7 (6), pp. e39311. Date of Electronic Publication: 2012 Jun 29.
DOI: 10.1371/journal.pone.0039311
Abstrakt: Background: Translational errors can result in bypassing of the main viral protein reading frames and the production of alternate reading frame (ARF) or cryptic peptides. Within HIV, there are many such ARFs in both sense and the antisense directions of transcription. These ARFs have the potential to generate immunogenic peptides called cryptic epitopes (CE). Both antiretroviral drug therapy and the immune system exert a mutational pressure on HIV-1. Immune pressure exerted by ARF CD8(+) T cells on the virus has already been observed in vitro. HAART has also been described to select HIV-1 variants for drug escape mutations. Since the mutational pressure exerted on one location of the HIV-1 genome can potentially affect the 3 reading frames, we hypothesized that ARF responses would be affected by this drug pressure in vivo.
Methodology/principal Findings: In this study we identified new ARFs derived from sense and antisense transcription of HIV-1. Many of these ARFs are detectable in circulating viral proteins. They are predominantly found in the HIV-1 env nucleotide region. We measured T cell responses to 199 HIV-1 CE encoded within 13 sense and 34 antisense HIV-1 ARFs. We were able to observe that these ARF responses are more frequent and of greater magnitude in chronically infected individuals compared to acutely infected patients, and in patients on HAART, the breadth of ARF responses increased.
Conclusions/significance: These results have implications for vaccine design and unveil the existence of potential new epitopes that could be included as vaccine targets.
Databáze: MEDLINE