White blood cells known as CD4+ T cells are the main target of HIV. The virus hijacks these cells and replicates within them, which ultimately destroys the cell. This depletion of the T cell population represents a major blow to the immune system and puts HIV-infected individuals at increased risk of opportunistic infections.
Treatment of HIV-infected individuals with a cocktail of drugs called combination antiretroviral therapy (c-ART) is able to restore the T cell population and help fight HIV infection, however not all patients respond to this therapy.
The growth factor interleukin-7 (IL-7) is known to stimulate T cell production and survival, suggesting that IL-7 may help restore the T cell population during HIV infection.
In a new study published in the JCI
, Yves Levy and colleagues at the University of Paris undertook a clinical trial to evaluate the safety and efficacy of repeated IL-7 therapy over a 16-day period in 13 c-ART-treated, HIV-infected patients that possessed low T cell counts despite successful suppression of virus levels with c-ART.
In these individuals, IL-7 was well tolerated and boosted the number of CD4+ and CD8+ T cells, which were able to mount an immune response against HIV. These effects were observed for 48 weeks. The data suggest that HIV-infected patients may benefit from intermittent therapy with IL-7 in combination with c-ART.