People with HIV and periodontal disease have higher levels of the virus in their saliva and plasma compared with HIV patients with healthy gingivae. (Photograph: Sherry Yates Young/Shutterstock)

Jan 7, 2015 | News Americas

CLEVELAND, USA: Researchers at Case Western Reserve University in the U.S. have discovered that byproducts of bacteria involved in periodontal disease are able to reactivate HIV in dormant T cells and cause the virus to replicate. Their findings may help explain why HIV patients with severe periodontitis have high levels of residual virus in their saliva and plasma, and suggest that HIV patients could benefit significantly from periodontal therapy.

In their study, which was recently published in the Virology journal, the researchers examined metabolic short-chain fatty acids from periodontal pathogens in particular. They observed that five short-chain fatty acid byproducts from two prevalent oral bacteria, namely Porphyromonas gingivalis and Fusobacterium nucleatum, are involved in activating T cells carrying latent HIV-1.

According to co-investigator Dr. Fengchun Ye, an assistant professor at the university's School of Dental Medicine, all humans have a reservoir of dormant T cells that are activated in response to inflammation to ward off infection in the body. However, in contrast to those in healthy people, these T cells can carry the latent HIV-1 virus in patients with HIV. The bacterial byproducts then act much like a jumper cable on a dead battery, Ye explained. 

The findings contribute to a better overall understanding of the little-researched microbiome in HIV disease and further support the notion that early treatment of bacterial infections is very important for dental patients with HIV. 

The study, titled "Short Chain Fatty Acids Potently Induce Latent HIV-1 in T-cells by Activating P-TEFb and Multiple Histone Modifications," was published in the January issue of the Virology journal.