HIV: Existing Drug Can Activate the Immune System

A new method to fight the human immunodeficiency virus (HIV) may already be accessible by reworking an existing prescription drug.

Adenosine deaminase (ADA) is an enzyme that may be able to activate the immune system to combat HIV. It may also be able to help the immune system ‘remember’ the virus so that a person does not get infected again — or make it so that it would be easier to treat in the case of reinfection.

“We need to find new strategies that will empower the immune system towards long-term control of HIV infection,” Luis J. Montaner, DVM, MSc, DPhil, editor-in-chief of the Journal of Leukocyte Biology, said in a news release.

The researchers compared ADA in cells in patients with HIV and healthy controls, as described in the report. Dendritic cells taken from blood cells were exposed to HIV-1 proteins or whole inactivated HIV-1 virus, either in the presence of ADA or without it.

When the cells were exposed to ADA it led to adenosine degradation and there was a reduction in regulatory T-cell mediated suppression. This means that T-cells, associated with immune responses, were more active.

“We hope this study puts ADA in the spotlight as a powerful immune modulator in vaccine strategies enhancing anti-HIV immune responses and limiting the need for life-lasting treatments,” continued co-author, Núria Climent, PhD, from IDIBAPS in Barcelona, Spain.

In addition, the ADA exposure increased the amount of CD4+ T cells, CD8+ T cell proliferation, and T-cell memory generation — which are also important players in immune responses. The researchers also observed an increase in the secretion of immunologically relevant Th1 cytokines.

“The availability of an approved drug that already targets the mechanisms described here ensures the quick translations of this work from the bench to the clinical,” Montaner concluded.