Immunological and virological characterization of HIV-1 viremia controllers in the North Region of Brazil

BACKGROUND A rare phenotype of clinical non-progressors to AIDS is not well understood and the new protocol for universal treatment, may block the understanding of viral control thus it is crucial to define this controversial group. METHODS A cohort of 30 persons followed a criteria for viremia control groups 1 (VC1; n = 2) and 2 (VC2; n = 7) and non-viral controllers (NC; n = 21) including number of years of diagnosis, LTCD4+, LTCD8+ counts, plasma viral load and the absence of ART; 241 uninfected control persons were matched to age and sex. Infected persons were regularly examined and submitted to two or three annual laboratory measurements. Polymorphisms and allele frequencies of CCR5Δ32 and SDF1-3'A were detected in the genomic DNA. Plasma levels of cytokines (IL-2, IL-4, IL-5, IL-9, IL-10, IL-13, IL-17 and IFN-y) were measured. RESULTS The group investigated is originated from a miscigenetic population and demographic and social characteristics were not significantly relevant. LTCD4+ median values were higher among VC than NC, but significantly lower than uninfected controls. Evolution of LTCD4+ and LTCD8+ counts, showed a slight increase of LTCD4+ among VC, but a significant decrease in the NC. The percentage of annual change in LTCD4+ was also significantly different between the groups. LTCD4+/LTCD8+ ratio was inverted but not significant among the VC, thus the ratio may be a useful biomarker for the VC. A clear signature indicated a change from Th1 to Th2 cytokine profiles from VC to NC, respectively. CONCLUSIONS The knowledge of viral controllers characteristics in different population groups is important to define a strict universal definition for the sake of learning about the pathogenesis of HIV-1. Data on LTCD4+ seems to be stable and repetitive from published data, but the LTCD8+ response and the significance of LTCD4+/LTCD8+ ratio values are in need to further exploration as biomarkers. The change from Th1 to Th2 cytokine profile may help to design and adjust specific treatment protocols for the group.