The HIV virus exploits the human body's natural mechanism for shutting down the immune system, but the process can be reversed, according to several new studies.

The Wall Street Journal reports that studies headed by researchers at Canada's Université de Montréal point to the tantalizing possibility that doctors one day could switch a patient's immune system back on, so that it could resume its fight against HIV, or even cancer cells, certain parasites or the virus that causes hepatitis C.

The studies, published in the journal Nature and its sister journal, Nature Medicine, build on almost 15 years of work by other researchers, including Kyoto University Prof. Tasuku Honjo, who in the early 1990s discovered a molecule, which he named PD-1, on the surface of disease-fighting T-cells.

The latest findings are preliminary, and there isn't any way to predict whether this avenue of research will ever yield new treatments. And there's several looming trouble areas, most notably that switching the immune system back on -- the most obvious treatment strategy -- might trigger autoimmune disease.

© 2006 GHCOM Partners, LLC. All rights reserved. GayHealth is a trademark of GHCOM Partners, LLC.