Patients with HIV on ART may have high viral levels, immune activation, and inflammation.
Even though antiretroviral therapy (ART) has improved treatment outcomes, some patients with HIV may still have small amounts of the virus in the blood and immune system activation, but a new study suggests these factors may not be related.
Previous research has shown a link between elevated immune activation and adverse events, such as heart disease. Understanding the reason why patients treated with ART experience this issue may address or prevent complications; however, the reason immune activation becomes elevated is unclear.
In a new study published by PLOS Pathogens, the authors examined whether immune activation is affected by low levels of HIV in patients treated with ART.
Included in the study were blood samples from 101 patients who participated in the AIDS Clinical Trials Group. The authors measured markers of HIV, immune activation, and inflammation before and after ART.
During treatment, patients had undetectable viral levels using conventional tests, but HIV levels in the blood were detected using a more sensitive approach, according to the study.
Prior to treatment, the authors discovered a correlation between HIV levels, immune activation, and inflammation; however, this correlation did not endure throughout treatment.
These results suggest that increased immune activation during ART was not the result of HIV in the blood, according to the study.
Instead, the authors noted that patients with high HIV levels prior to treatment had higher levels during treatment, despite a significant reduction. Patients with high pre-treatment levels of inflammation and immune activation also displayed signs of higher levels during treatment, even though ART controlled the virus, according to the study.
This suggests that pre-treatment levels of the virus, immune activation, and inflammation may impact the levels during ART, according to the study. This also suggests that HIV levels may not be a factor affecting immune activation.
“We need to understand why events that happen before treatment is started continue to impact activation many years afterwards, despite the fact that the medicines are holding the virus in check,” the authors wrote. “We also need to diagnose and treat HIV earlier to prevent immune damage that may lead to heightened activation."
A better understanding of the virus itself and why viral levels, immune activation, and inflammation remain high regardless of successful treatment will likely lead to more effective treatments, according to the study.
Additionally, the authors hypothesize that curative treatments may need to take a different approach than current drugs.
"Interventions aimed at curing HIV may differ from those needed to decrease activation,” the authors wrote.
The authors state that these findings may lead to novel HIV treatments or a potential cure for the infection, according to the study.
“We anticipate that these and other findings from this study will inform future interventions designed to reduce HIV-1 reservoirs and persistent inflammation and immune activation in individuals on long-term ART,” the authors concluded.