Feature Story

AIDS at 20: A Look Back, A Look Ahead with World-Renowned Scientist Dr. Robert Gallo

By Noel Holton
University of Maryland Medical System Web Site Writer
-Reprinted with permission from the University of Maryland Medicine's Web site (www.umm.edu)

In their quest to find cancer-causing viruses, a group of National Cancer Institute (NCI) scientists made history 20 years ago when they discovered HIV, the virus that causes acquired immune deficiency syndrome (AIDS).

Led by Dr. Robert Gallo, former director of NCI's Laboratory of Tumor Cell Biology, the scientists were in search of a class of viruses called retroviruses, when the AIDS pandemic emerged.

AIDS was first described in the Centers for Disease Control Morbidity and Mortality Weekly Report on June 5, 1981. At that time, health officials were alarmed by the new disease, which was striking gay men by destroying their immune systems.

Gallo's research into retroviruses -- viruses that merge with the cells they infect -- proved pivotal in understanding the nature of AIDS. A few years after the CDC report was published, Gallo, who is now the director of the Institute of Human Virology (IHV) at the University of Maryland Biotechnology Institute, was able to link the retroviruses his research team was studying to AIDS.

“We were learning a lot about retroviruses,” said Gallo. “By 1980, we had found a virus that had caused leukemia in parts of Africa, Japan and Southeast Asia. We later found out it also caused neurological disorders. We then discovered a second retrovirus and learned more about how it targeted T-cells (the white blood cells that control the body's response to infection).”

By 1983, Gallo and his team had isolated a new retrovirus in a patient. They knew that this virus was spread from person to person through the blood and sexual contact.

“Within a year (of isolating the retrovirus), we were confident that we had found the virus that caused AIDS,” he said. “It was during the spring of 1984 that we were able to announce, along with the French, our breakthrough by publishing our findings in the medical journals The Lancet and Science.”

What Is On the Horizon?

Gallo's early research at NCI led to the development of the first HIV blood test. This blood test made it possible, for the first time, for scientists to track this deadly disease and define the magnitude of its devastation. It also allowed the medical community to identify patients prior to their developing AIDS. Gallo's work today at IHV is no less important in the fight against AIDS.

Gallo and his research team at IHV are working on the development of an HIV vaccine to stem the global spread of the virus. They also are looking into ways to help patients avoid the unpleasant side effects of the current AIDS drug therapies.

“We feel we are one of the most progressive institutes in the world in terms of both clinical studies and vaccine research, said Gallo. Not only are we working on developing preventive vaccines against HIV, we are also looking at biologic therapies that are less toxic for patients than the drugs that are available now.”

Although IHV is focused on eradicating HIV, there are other diseases that are a part of its mission. IHV scientists also are studying multiple sclerosis, various forms of cancer, and several other kinds of viruses not related to HIV.

In addition to their role as researchers, many IHV doctors who specialize in viral diseases play a hands-on role in treating patients throughout the Baltimore area. They provide inpatient care at the University of Maryland Medical Center, long-term, chronic care at University Specialty Hospital and outpatient care at the Evelyn Jordan Center.

“The biological therapies we are working on involve using natural substances in the body such as peptides that can kill tumor cells and block HIV from entering and infecting cells,” Gallo said.

Retroviruses such as HIV function by inserting their genes into ours. They target the cells in the blood, merging their genes with chromosomal DNA. What makes retroviruses so difficult to treat is that when infected cells divide, they take the viral genes with them so the infection never goes away.

In May 2000, Gallo and his team were awarded a grant from the International AIDS Vaccine Initiative to develop an oral vaccine derived from bacteria that would deliver genetically encoded material to human cells. Patients are being recruited for Phase I clinical trials.

The Institute of Human Virology also received a $7 million grant from the National Institutes of Health to collaborate with researchers around the world on a preventive vaccine.

As part of the Maryland/Israel Visiting Fellows Program in Biotechnology, Israeli scientist Dr. Jonathon Gershoni of Tel-Aviv worked this past summer with Gallo's team to modify the HIV envelope. This approach will build upon the discovery that using an HIV coat protein could be valuable in preventing HIV from gaining entry into human cells.

Playing It Safe Still The Best Option

Despite the fact that researchers are moving closer to major advancements in preventing and treating HIV, Gallo is concerned that people may not be as diligent about practicing safe sex and avoiding risky behaviors today as in the past.

Recent studies conducted by the San Francisco Department of Public Health have hinted at a resurgence of HIV among gay and bisexual men. As for heterosexuals, CDC statistics show that about 15 percent of all AIDS cases are the result of heterosexual activity, and that the number of heterosexual adolescents infected with HIV doubles every 14 months.

“Sure, we have drugs that will treat AIDS, but these drugs are in no way a cure,” Gallo said. “These drugs can suppress the virus, but you must take them for the rest of your life and they are expensive, which makes them a nightmare for the Third World. We also see a lot of toxicity with these drugs, and through overuse they can cause the virus to mutate. We are working hard to create a vaccine and less toxic treatments, but we aren't there yet. People cannot afford to be complacent about prevention.”

As for the future, Gallo is optimistic. In fact, he envisions the discovery of an HIV vaccine, along with various improvements in AIDS treatment, within the next decade.

“Yes, I think there is certainly a possibility that we will have a vaccine by then,” he said. “I'm not saying it will be perfect or available on a wide scale, but, yes, in some form, I think there will be a vaccine. I also think we will have some very good biologically based drugs available that won't have the toxicity and negative side effects of the current AIDS drugs. We are already starting to see some of these. I'd be disappointed if in 10 years we hadn't made it that far.”

For additional information contact Gwen Newman, Institute of Human Virology, 410-706-4616.
E-Mail: Gwen Newman (newmang@umbi.umd.edu)