The Role of Gut Bacteria in HIV Immune Recovery

Therapies that target certain gut bacteria may prevent complications and improve the efficiency of antiretroviral therapy.

New findings reveal the effect of gut bacteria on the immune recovery of HIV patients, suggesting the potential development of complementary therapies that target these bacteria to improve the efficiency of antiretroviral treatment (ART).

A study published in eBioMedicine analyzed gut bacteria found in the fecal matter of healthy subjects and HIV patients undergoing different intensities of infection control and immune recovery.

The primary focus was to evaluate the activity levels of bacteria in the gastrointestinal tract. Researchers discovered there was a correlation between immune recovery and the behavior of a certain subset of gut bacteria in response to treatment; both a consequence and cause of recovery.

“HIV patients suffer from persistent immune deficiencies and chronic intestinal inflammation caused, in part, by the very toxins released by the cells to fight off the HIV infection,” said researcher Manuel Ferrer. “In this study we have found that, in some patients, certain gut bacteria become activated during ART and begin to amass anti-inflammatory molecules. The immune recovery of these ‘ART responders’ is much better than that of their peers, the make-up and behavior of whose gut bacteria does not lead to the same anti-inflammatory effect.”

The authors noted that the results suggest a correlation between bacterial activity and immune response as a consequence of HIV and ART.

“The make-up and behavior of the gut bacteria of HIV patients whose body responds adequately to antiretrovirals are different to those who respond less well to treatment,” said researcher Sergio Serrano-Villar. “It is possible that the reason why some subjects respond better to antiretrovirals is because their immune system is predisposed to these beneficial, recovery-enabling bacteria.”

Since gut bacteria seems to play a role in the success of immune recovery in HIV-positive individuals, then ART could have a greater impact on HIV patient health if it is combined with therapies that specifically target this subset of bacteria.

Additionally, the current study could help in the design of new therapies for the prevention of complications associated with immunodepression and chronic inflammation, the researchers concluded.