Immune Boost Shows Promise Against AIDS

A new study has raised some hopes that the immune system can be fortified with one of its own chemical messengers to increase the effectiveness of drugs against the AIDS virus.

In a report in the 31 October New England Journal of Medicine, Joseph Kovacs, Clifford Lane, and colleagues at the National Institute of Allergy and Infectious Diseases treated 60 HIV-infected people with either a combination of anti-HIV drugs or the drugs plus an immune system protein called interleukin-2, or IL-2. After 1 year, the 29 patients who received IL-2 had more than twice as many CD4s--white blood cells that HIV targets--as the controls.

"I'm very enthusiastic about this," says Jay Levy, a retrovirologist at the University of California, San Francisco. "We need more studies of this nature that aim to restore immune function and not just focus on the destruction of the virus."

In the Il-2 group, CD4 cell counts rose, on average, from 428 to 916 per cubic millimeter of blood. In the control group, meanwhile, CD4s dropped from an average of 406 to 349. (Healthy, uninfected people generally have a count greater than 600.) The findings verify similar results from a pilot study by the Kovacs and Lane group published last year in the same journal.

The researchers have yet to prove that the patients with increased CD4 counts are healthier. And this gives AIDS clinicians like Robert Schooley of the University of Colorado serious reason for pause. Although the data are "fascinating," Schooley says, he's concerned about the treatment's high costs and the heavy fatigue it tends to cause. Studies underway, however, are meant to answer the big question: whether the IL-2 regimen will lead to longer, healthier lives for HIV-infected people.