Integrative genomic and cellular analyses of blood and T cells from HIV-1 controllers reveal a low inflammatory profile associated with strong HIV-specific adaptive responses [PBMC]

Without treatment, HIV-1 infection is characterized in the majority of individuals by a detectable HIV replication and a rapid decline in CD4+ T lymphocytes leading to AIDS. However, a minority of patients, called HIV Controllers (HIC), maintains spontaneous control of HIV replication and for a large part, normal CD4+ T cell counts. The mechanisms leading to this spontaneous virus control are not fully known. We used gene expression and functional cellular analyses to compare EC and chronically HIV-1 infected individuals with controlled virus replication under combined antiretroviral therapy (cART). In the blood, EC individuals are characterized by a low inflammation, a down modulation of NK inhibitory cell signaling and an up regulation of T-cell activation gene expression profiles. Interestingly, in contrast to cART individuals, this balance persists following in vitro stimulation of cells from HIC with HIV antigens. This favourable genetic profile in HIC was also consistent with functional analyses showing a bias towards a Th1 and cytotoxic T cell profile and a lower production of inflammatory cytokines. Finally, taking advantage of the characterization of HIC based upon their in vitro CD8+ T lymphocyte capacity of killing HIV-infected cells, we show that unsupervised genetic analysis of differentially expressed genes fits clearly with this cytotoxic activity allowing the characterization of a specific signature of HIC individuals. Globally, these results reveal significant features of HIC making the bridge between cellular function and gene signatures and the regulation of inflammation and killing capacity of HIV-specific CD8+T cells. Moreover, these genetic profiles are consistent through analyses performed from whole blood to PBMC and at the T-cell population levels. Likely, these data help to define the goals of immunotherapeutic approaches in the perspective of HIV-1 functional cure. These strategies would need to induce both strong HIV-1-specific immune responses whereas minimizing inflammation.

81