San Francisco Chronicle; Thursday, July 2, 1998
David Perlman, Chronicle Science Editor

If early trials in patients prove it can be done, the achievement would free many AIDS patients from the devastating bacterial infections that can condemn them to painful deaths.

Scientists at major institutions in Paris and Boston described their latest efforts at achieving the long-sought goal of "immune reconstitution" in presentations to rapt audiences at the 12th World AIDS Conference in Geneva. Some experts indicated that the goal is indeed realistic given more experimental work.

In one report, Dr. Brigitte Autran, a leading virologist at the Pitie-Salpetriere Hospital in Paris, described the progress of 161 severely ill AIDS patients who were treated for 18 months with three powerful anti-viral drugs, including one of the new protease inhibitors.

During that time, the levels of HIV, the AIDS virus, dropped to undetectable levels in the blood of the patients, although some latent viruses -- as scientists have known for years -- remained sequestered as reservoirs in certain cells and lymph tissues.

More significantly, however, levels of newly formed and uninfected CD4 cells -- the crucial cells of the immune system that the AIDS virus first invades -- rose four-fold, while other valuable cells called cytotoxic T lymphocytes that attack virus-infected cells rose, too.

"Dr. Autran's work is among the best in showing that at least partial reconstruction of the immune system is possible," said Dr. Anthony S. Fauci, one of the world's leading AIDS researchers and director of the National Institute of Allergy and Infectious Diseases in Bethesda, Md.

The emergence of the new and valuable CD4 cells in Autran's experiments poses an unsolved mystery, Fauci said, because those cells are normally formed by the thymus gland, which is an organ that shrivels and ceases to function in adults.

"But now is the time to ask the really tough questions," Fauci added, "and that is to see if they're going to get immune reponses active against infectious organisms."

But Autran had a ready answer. She reported that the new and uninfected "naive" CD4 cells that had emerged in such large quantity in her patients proved capable in laboratory experiments of attacking such organisms as those that cause the opportunistic infections of AIDS like tuberculosis, candididiasis, toxoplasmosis and even cytomegalovirus disease.

Until such power in apparently restored immune systems is fully tested in human trials however -- and most specifically in AIDS patients -- it will not be possible to know that the achievement is truly complete, Autran agreed.

"Although we need more and larger studies to learn whether full reconstitution of the immune system against opportunistic infections -- and perhaps even against HIV -- is possible, we do believe that recovery of CD4 cells is achievable in advanced disease," Autran said. "It is dependent on highly active anti-retroviral therapy that keeps the viral load of HIV down to undetectable levels for long periods."

In another report, Dr. Bruce Walker, an AIDS researcher at Harvard's Massachusetts General Hospital, described how he, too, has restored the damaged immune systems of a group of patients who had just developed the first acute symptoms of illness that mark new HIV infection.

Walker first treated the patients with an anti-viral drug called Didanosine, also known when it was still experimental as ddI, plus hydroxea, a well-known drug used in treating leukemia, and a painkiller in other diseases.

Then, after two years of treatment with a combination of anti- virals that lowered their virus to undetectable levels, Walker, too, found evidence that his patients had developed strong "immune reponses."

Walker is so convinced of the potential for restoring a functioning immune system to AIDS patients that he suggested a carefully controlled clinical trial to learn whether this new "immunotherapy" might even make it possible to stop all other therapy and let the recovered immune systems do the work on their own against the opportunistic infections of AIDS.

980702
SC980703

Always watch for outdated information. This article first appeared in 1998. This material is designed to support, not replace, the relationship that exists between you and your doctor.

AEGiS presents published material, reprinted with permission and neither endorses nor opposes any material. All information contained on this website, including information relating to health conditions, products, and treatments, is for informational purposes only. It is often presented in summary or aggregate form. It is not meant to be a substitute for the advice provided by your own physician or other medical professionals. Always discuss treatment options with a doctor who specializes in treating HIV.

Copyright ©1980, 1998. AEGiS. All materials appearing on AEGiS are protected by copyright as a collective work or compilation under U.S. copyright and other laws and are the property of AEGiS, or the party credited as the provider of the content. .