Study of Leukemia Virus Helps Search for Treatment for AIDS

Research on a virus that causes a special kind of leukemia in Japanese and Caribbean Islands adults may now be leading scientists to find a way to prevent the severe damage to the immune system caused by a related virus that is responsible for AIDS, an American scientist said Monday.

Dr. Robert Gallo, the National Cancer Institute researcher who first isolated both the leukemia virus and the AIDS virus, said recent work by scientists at other centers indicates that it may be possible to prevent the AIDS virus’s destruction of key cells in the human immune system.

These cells, called T-cells, protect the individual from a variety of infections that are responsible for the high mortality rate of patients with AIDS, or acquired immune deficiency syndrome.

Gallo and three Japanese scientists on Monday were awarded this year’s Armand Hammer prize for significant advances in cancer research. Hammer, chairman and chief executive officer of Occidental Petroleum Corp. and the chairman of the cancer panel that advises President Reagan on the disease, has been presenting the award for the last three years.

The Japanese scientists are Dr. Yorio Hinuma, Kyoto University;Dr. Isao Miyoshi, Kochi Medical School, and Kiyoshi Takatsuki, Kumamoto University School of Medicine.

They will share the $100,000 prize for their independent research and subsequent collaboration that led to the isolation of the virus that causes the special type of leukemia.

Called HTLV-I, for human T-cell leukemia virus Type I, the virus is found in the southern part of Japan and in some parts of the Caribbean, especially Jamaica and Trinidad. The virus is also found to a lesser degree in the Southeastern United States.

According to Takatsuki, who is a blood specialist, work on human T-cell leukemia began in Japan about 10 years ago but has not yet resulted in a good treatment.

“It is very malignant,” he told a news conference at the awards presentation. About one in every 100 Japanese contracts this leukemia during his or her lifetime. Many more are known to be infected by the HTLV-I virus, but for reasons as yet unknown do not develop symptoms.

With assistance from the Japanese scientists, Gallo isolated the leukemia virus in 1980 while taking part in the treatment of two Americans who had been stricken with the disease.

The virus attacks an element of the immune system called T-4 cells. Not long after HTLV-I had been isolated, researchers for the first time became aware of the disease now known as AIDS.

Gallo was struck by some of the similarities between human T-cell leukemia and AIDS. The observation that AIDS patients, like the leukemia patients, had severely impaired T-cell function--together with the fact that AIDS results in the patient getting various kinds of opportunistic infections--gave Gallo the idea to look for a virus that is similar to HTLV-I as the cause of AIDS.

Using the experience gained in finding HTLV-I, Gallo and his colleagues last year successfully isolated the AIDS virus, which is known as HTLV-III.

Since that time, it has also been learned that HTLV-I, like its AIDS virus counterpart, can be transmitted in semen and can be passed to an offspring before birth. Recently, a Japanese scientist reported that in his country HTLV-I always is transmitted from man to woman, never the reverse. The possible significance of this for AIDS is not known.

Not Identified Before

Meanwhile, Gallo said research by scientists at UCLA, Harvard and in Japan indicates that the destructive effect of HTLV-I is due to a special gene--one never before identified--which the virus introduces into the genetic material of the T-4 cells.

Gallo said it is believed that this new gene produces a protein that causes the T-cells to proliferate endlessly, as in cancer.