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AIDs virus hidden

in body's T-cells

hard to eliminate

ISLAMABAD: The Aids virus can hide in the body, immune to the most powerful drugs, making it likely that it will be many years before a cure is found.

Research by microbiologists at the University of Minnesota shows that within three days of infection the HIV virus can invade "resting T-cells".

Scientists are of the view "these cells are good hiding places because they are inactive and so ignored by the body's immune system. Neither can they be attacked by drugs, which need some kind of activity by the virus or the cells it infects in order to work.

No drug currently available could find the virus in its hiding place and kill it, the scientists added.

Ashley Haase, reporting the findings in the Journal Science, said: "These cells fly below the radar screen of the immune system. They also live for a long time and won't be affected by our current combinations of anti-Aids drugs".

HIV causes illness by infecting immune system cells known as CD4 T-cells. When the virus gets inside, it takes over a cell's machinery and makes it crank out copies, killing the cell. As long as this is happening, the body's other immune cells can detect the activity and attack while drugs can stop various stages of the takeover process.

This explains why cocktails of HIV drugs can help to suppress the virus. But the research shows that HIV is also able to enter inactive or "resting" T-cells which can exist in the body for years, even decades, without doing anything.

Haase's team, working in monkeys and later HIV patients, discovered that the virus can invade within three days of infection before symptoms are shown.

Dr Anthony Fauci, head of the National Institute of Allergies and Infectious Diseases, said the study helped to explain why people who took cocktails of drugs for years were not cured.ÑAPP