Restoring immune function in HIV patients: Therapies targeting PD-1 and IL-10 molecules needed

VGTI FloridaMar 17 2010

New research conducted by the scientific director for VGTI Florida and his colleagues at the University of Montreal, in collaboration with scientists from the NIH and the McGill University Hospital center, may soon lead to an expansion of the drug arsenal used to fight HIV. The research sheds new light on how HIV gradually weakens the body’s immune system and highlights the need for new research into therapies that will target the chain of events that cause the progression of the disease.

“We are the first to show that these two molecules work together to shut down the  function of CD4 T-cells in HIV patients. This in turn, may lead to paralysis of the immune system and an accelerated disease progression”

The study, published in the journal Nature Medicine, describes the pivotal role of two molecules, PD-1 and IL-10, in impairing the function of disease-fighting T-cells known as CD4 T-cells – a phenomenon that weakens the body’s immune system.

Specifically, the researchers found that when HIV invades the body, bacterial products are released from the gut and white blood cells respond by releasing a protein on the surface of the cell called PD-1. Heightened levels of PD-1 lead to the activation of a gene that produces another protein called IL-10. Both of these proteins (PD—1 and IL-10) are known to appear at increased levels during HIV infection.

“We are the first to show that these two molecules work together to shut down the function of CD4 T-cells in HIV patients. This in turn, may lead to paralysis of the immune system and an accelerated disease progression,” said Dr. Rafick-Pierre Sékaly, scientific director of VGTI Florida, a professor at the University of Montreal and researcher at the Research Center of the University of Montreal Hospital Center.

“Our results suggest that it is important to block both IL-10 and PD-1 interactions to restore the immune response during HIV infection,” said Dr. Sékaly. “We believe that immunotherapies that target PD-1 and IL-10 should be part of the arsenal used to restore immune function in HIV-infected subjects.”