For a long time, it was thought that HIV stocks were inactive, namely that HIV reservoirs were dormant. However, scientists from Switzerland and Canada have discovered that some of these cells produce RNA and proteins of the virus spontaneously, which can change the response of the immune system of patients.
Experts from the University of Lausanne and the University of Montreal believe that HIV is a deceptively dormant virus. It continues to act and affect the immune system of people who are undergoing treatment.
Research
The results of the study were published in the journal Cell Host & Microbe. It involved 18 people living with HIV who were taking antiretroviral therapy and had a suppressed viral load for at least three years. Using the laboratory method of RNA flow cytometry, experts divided CD4+ or “helper” T-cells according to whether they were infected with HIV and the type of virus they produced.
14 of 18 patients (78%) had HIV reservoirs that spontaneously produced viral RNA, the study found. 7 of the 18 (39%) reservoirs also produced viral proteins, including p24, which is a component of the HIV envelope.
The study found that the viral RNA and protein fragments were enough to trigger an immune response, even though they were non-functional “rubbish” unable to cause infection. Scientists believe this may be important because a proportion of people who successfully take antiretroviral therapy experience negative consequences of living with HIV, such as weakness, premature osteoporosis, accelerated cardiovascular disease and others.
So which cells contain active HIV reservoirs?
Scientists have found that reservoirs in memory cells and Th17 cells, which are involved in the immune defense of the gut, show the greatest activity in producing RNA and proteins of the virus. However, HIV is not found in one particular type of CD4+ T cell, although it can be present in any of these cells.
Brief conclusions of the research
The authors hypothesized that the immune response induced by the virus RNA and proteins may have no effect; however, more research is needed to confirm this hypothesis.