Immune activation and inflammation persist in the majority of treated HIV-infected individuals and is associated with excess risk of mortality and morbidity. A new study by BUSM researchers suggests that use of HIV RNA expression inhibitors as adjunct therapy might diminish atypical inflammation and restore immune function in HIV-infected individuals on combination antiretroviral therapy (cART).

HIV-1-infected individuals have an excess risk of developing non-AIDS complications, such as cardiovascular atherosclerosis, neurocognitive dysfunctions, non-AIDS cancers, osteoporosis, and renal disorders. Systemic chronic immune activation has been postulated to lead to these non-AIDS complications.

Despite long-term viral suppression by cART, it has remained unclear how chronic inflammation is induced in HIV-infected individuals. In this study, BUSM researchers identified a mechanism of HIV-1-induced chronic immune activation and T-cell dysfunction. In studies performed with primary human macrophages and T cells, they found that persistent infection of macrophages with HIV-1 and expression of intron-containing HIV-1 RNA alone even in the absence of infectious virus production lead to induction of type I interferon (IFN-I)-dependent pro-inflammatory responses and immune exhaustion of co-cultured T cells. They believe that these findings might provide an explanation for the observed chronic inflammation-associated morbidities in HIV-infected individuals who are on cART.

“We hope our study will broaden knowledge of host-HIV interactions and might help to reduce inflammation-associated disorders caused by chronic viral infections,” said Rahm Gummuluru, PhD, corresponding author and associate professor of microbiology.

These findings appear online in the journal Nature Communications.