about AIDS

Fighting a Virus with a Virus: A Futuristic Trojan Horse? Dave is an HIV-positive person who is undergoing therapy for his infection, trying to keep the virus from wrecking his immune system and leading to AIDS. At the clinic he is injected with another kind of virus which seeks out his own infected cells and destroys them, in the process killing the HIV inside them.

Sound bizarre? Some version of this may not be too far in the future, as a result of cellular research now underway. Scientists at Yale and at a German federal lab have genetically engineered viruses which in the test tube enter only HIV-infected cells. The lab virus was re-designed to carry the receptor and entry co-receptor proteins which HIV itself uses to enter the human T-cell. Such a virus could be designed to kill the infected T-cell (and its HIV) or to deliver drugs directly into the cell to disrupt the HIV.

Much work remains before such engineered viruses can be used in human patients, but application of the technology could be easily shifted to use with liposomes, which have years of research behind them for delivering drugs directly into targeted cells. (Such liposomes are spheres of fatty substance surrounding a drug solution, designed to be attracted to and taken in by a particular type of cell.)

Use of the engineered virus, however, is intriguing because in the laboratory cell culture, it reproduced and kept attacking HIV which emerged from a dormant state somewhere in the culture. Of course, introducing any genetically engineered virus into people carries grave considerations which must be answered fully before even basic human trials begin. Futher cell culture research and monkey studies come first.

Repeatedly throughout the AIDS epidemic, stunning medical advances such as this have been made which have broad applications far beyond HIV disease. It's tragic that it has taken the yearly deaths of tens of thousands from AIDS to prod science into exciting new avenues, but the ultimate benefit to people with HIV, and to all of medicine, is immeasurable.

(For a full discussion of this research, see the September 5 issue of the journal CELL.)

-- Sandy Bartlett, Information/Education Coordinator, AIDS Services of Austin