PARIS - A team of researchers at the Cytokine Genetics and Differentiation Laboratory of the Institut Curie, in Orsay, has successfully tested an in vitro gene therapy for combating HIV infection using the interferon-B gene.

The trial concerned a single type of cell in the immune system, lymphocytes. The interferon-beta gene produces an antiviral protein that inhibits replication of the HIV virus at different stages of the infection cycle.

To start the gene therapy, a retroviral vector containing a human interferon-beta gene was introduced into isolated white blood globules. Being incorporated in a retroviral vector enabled the interferon-beta gene to express itself spontaneously, producing the antiviral protein in a continuous fashion and rendering the modified cell resistant to HIV infection.

In a second stage, conducted in conjunction with the Rothschild Hospital, in Paris, the gene was introduced into lymphocytes taken from patients suffering from AIDS, and was found to inhibit in vitro propagation of the virus carried by the patients. The researchers also found that the continuous production of small quantities of interferon-beta restored the immune function of the lymphocytes taken from HIV-infected patients against the numerous infections to which they are exposed.

All these experiments took place on cells cultured in the laboratory, which implies that this therapy could be tested in trials aimed at studying the development and behavior of the modified cells in the organism, using animal models. *