Increased IL-8 levels in HIV-infected individuals who initiated ART with CD4+ T cell counts <350cells/mm3 - A potential hallmark of chronic inflammation.

The identification of inflammatory markers in HIV+ individuals on ART is fundamental since chronic ART-controlled HIV infection is linked to an increased inflammatory state. In this context, we assessed plasma levels of pro-inflammatory cytokines (IL-1β, IL-8, and IL-12p70) of HIV+ individuals who initiated ART after immunosuppression (CD4+ T cell counts <350cells/mm3). HIV+ individuals were stratified according to two extreme phenotypes: Slow Progressors (SPs; individuals with at least 8 years of infection before ART initiation) and Rapid Progressors (RPs; individuals who needed to initiate ART within 1-4 years after infection). A control group was composed of HIV-uninfected individuals. We found increased IL-8 levels (median: 5.13pg/mL; SPs and RPs together) in HIV-infected individuals on ART as compared to controls (median: 3.2pg/mL; p=0.04), although no association with the progression profile (slow or rapid progressors) or CD4+ T cell counts at sampling was observed. This result indicates that IL-8 is a general marker of chronic inflammation in HIV+ individuals on ART, independently of CD4+ T cell counts at the beginning of the treatment or of the potential progression profile of the patient. In this sense, IL-8 may be considered a possible target for novel therapies focused on reducing inflammation in chronic HIV infection.