The New York Times - December 12, 1986
Erik Eckholm

In a report to be published today, the researchers theorized that the action of these suppressor T-cells, one of several types of blood cell involved in the body's response to disease agents, may explain why some people infected with the AIDS virus have not become ill. Possibly, they said, patients who have become sick could be treated by enhancing the body's supply of suppressor T-cells.

"This is the first indication that individuals have in themselves a means of controlling the virus," said Jay A. Levy of the University of California at San Francisco, a virus expert who is the leader of the research team.

Other scientists said the findings were intriguing but urged great caution in their interpretation.

'Big Jump' to the Patient

"There's a big jump between the test tube and the living patient, and we should be careful about extrapolating," said Martin S. Hirsch of the Massachusetts General Hospital, an expert on the treatment of acquired immune deficiency syndrome.

Dr. Levy said the new laboratory results bolstered his belief that many individuals with healthy immune systems could control the AIDS virus without the fatal effects that occur with the disease. He and his colleagues have argued that the infection tends to cause disease only in individuals whose immune systems have been severely weakened, as by a chronic infection with another disease.

The San Francisco team, which also included Dr. Christopher M. Walker, Dr. Dewey J. Moody and Dr. Daniel P. Stites, said they were unable to find active AIDS virus in the blood of half of individuals whose blood carried antibodies to the virus. The presence of antibodies indicates the virus has entered the body.

In addition, active virus was not detectable - and had not been detected for more than a year - in the blood of others where it had previously been been evident, suggesting "a control of the virus infection," according to the report in the journal Science.

Dormancy of Virus Noted

Other experts described this assertion as highly speculative. Many scientists believe evidence indicates that most, if not nearly all, of those with antibodies will carry the virus indefinitely and say there is no way to predict the long-term consequences. They note that the virus can lie dormant in body cells but later resurge and that it is extremely difficult to detect even in an active state. Some experts argue that with time, a high proportion of those carrying the AIDS virus will develop AIDS or neurological disorders.

"I think that real evidence about how people handle the AIDS virus can only come from long-term epidemiological studies," in which infected individuals are followed over the course of their lives, said Dr. William Haseltine of Harvard University.

A committee of the National Academy of Sciences recently predicted that 25 percent to 50 percent of virus carriers would develop AIDS within 5 to 10 years of infection. The committee did not speculate about the prospects beyond that. Federal officials have guessed that as many as 1.5 million Americans are infected with the virus, designated variously as HIV, HTLV-3 or LAV.

The San Francisco researchers studied blood samples from three healthy men who had antibodies to the AIDS virus, indicating prior infection, but had no detectable virus in their blood. When T-cells with a protein called CD8, a class that includes suppressor T-cells, were removed from the blood samples, the virus began to grow in the samples. This, the researchers said, indicated that the removed cells had been preventing viral reproduction.

Halt of Duplication Theorized

They added the CD8 cells back into a sample and duplication of the virus was again inhibited. Further research suggested that cells from the patient's own blood were more effective at inhibiting the virus than cells from the blood of others and that the suppressor T-cells in particular were producing an unidentified substance that attacked the virus.

The team theorized that the suppressor T-cells helped prevent duplication of the AIDS virus and development of disease in humans, although they conceded this was "not yet clear." The findings, they said, suggest that AIDS patients could be treated by removing these cells from their blood, building their numbers with the help of a substance from the body, such as interleukin-2, then returning them to the patient.

This approach may have an important advantage over direct use of such natural immune-enhancing agents as interleukin-2, the scientists suggested. Interleukin-2 stimulates production of another type of blood cell, helper T-cells, which the AIDS virus attacks and uses for duplication. External enhancement of suppressor cells might permit a strengthening of antiviral activity without providing "additional target cells" for AIDS virus growth, the report said.

As an idea for treatment, this is "an interesting concept, but it may prove difficult in practice," Dr. Hirsch said. He said many scientists expected that the most effective therapies would involve a combination of drugs that impede the virus directly and methods of reconstituting the immune system such as that being suggested by Dr. Levy.

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