Gene therapy to cure AIDS

It is too early to know whether the first scientific work of this kind will become a priest, or a new treatment. The investigation was only intended to show that so far, the therapy appears feasible and safe.

The idea was based on the surprising case of a patient with AIDS appears to have been cured through the transfusion of blood cells from a donor with a natural immunity to HIV for almost four years in Berlin. Researchers seek a more practical way to achieve a similar immunity through their own blood cells of patients.

The results, announced in Boston, sparked cautious optimism among experts.

"For the first time, people begin to think of a cure" as a real possibility, said Dr. John Zaia, director of governmental group that oversees gene therapy experiments.

Even if the new approach did not get completely eradicate HIV, the virus that causes the disease, could reconstitute the immune systems of patients to the extent that they can control it without drugs against AIDS, "what is known as a cure functional", he said.

Carl Dieffenbach, responsible for matters related to AIDS at the National Institute of Allergy and Infectious Diseases, agreed.

"We hope this is enough to generate a level of immune reconstitution was similar to that observed in patients in Germany",  he said.

This is the first time that researchers can permanently delete a human gene; we modify the cell structure and re-inoculated patients. Other attempts at gene therapy were to incorporate a gene or other moderate activity and do not work against HIV.

The virus can damage the immune system for years before people develop symptoms and then being diagnosed with AIDS (stands for acquired immunodeficiency syndrome). Usually enters cells through a receptor protein, or "base ", called CCR5.

Some people (almost 1% of whites and least in the case of minorities) lack the CCR5 gene and have a natural resistance to HIV. In 2007 a person with that particular blood stem cells donated by an American based in Berlin who had leukemia and HIV.

Cell transplantation appears to have cured two evils, but finding similar donor for all people with HIV is possible, and transplants carry a medical risk.

In the study, six HIV-positive men were subjected to blood filtration to remove a small percentage of T lymphocytes, responsible for coordinating the cellular immune response. The resulting compound of the blood was taken to a lab and almost a quarter of the cells were modified. The cells were combined with growth factors to multiply and then were returned to patients.

Three months later, five men were three times the number of modified cells was expected.

In the six patients, anti-HIV cells were thriving for almost a year after the transfusion, even in tissues that can hide the virus when it cannot be detected in the blood.

However, there are still several unanswered questions such as whether HIV could find other ways to enter the cells and the cost of treatment.

"I may not live as long as for a cure, but always waited for an opportunity", said Jay Johnson, who is 50 years and received treatment in September.