COCAINE AND INTENSITY OF H.I.V. ARE RELATED IN A STUDY OF MICE
By Denise Grady
New York Times 15 Feb. 2002
Research in mice may help explain something that doctors
have noticed in people who are infected with H.I.V.:
cocaine use seems to make the disease progress faster and
lead to more of the opportunistic infections that are the
hallmark of AIDS.
The reason is not known. Drug abusers often eat poorly,
have unprotected sex and neglect their health in other
ways, so it has been impossible to tell whether their
problems are due to cocaine itself or to the other habits
that often go with addiction.
A new study suggests that cocaine is to blame. In the
study, by researchers at the AIDS Institute at the
University of California at Los Angeles, specially bred
mice were inoculated with human cells and with H.I.V., the
virus that causes AIDS, and then given injections of either
cocaine or a salt-water placebo. Cocaine greatly enhanced
replication of the virus and increased the number of human
cells it infected and killed.
Dr. Gayle C. Baldwin, who directed the study, said, "We're
talking about a 200-fold increase in viral load in these
animals. That is a lot."
In addition, Dr. Baldwin said, the mice given cocaine had
only one- ninth as many CD4 cells as the mice given salt
water. CD4 cells, also called helper T cells, help to
activate other cells of the immune system. They are the
prime targets of the AIDS virus, and when they are wiped
out, the ability to fight off infections is lost.
The virus also infects other cells, and, Dr. Baldwin said,
"We're seeing that the population of cells that are not
killed off are churning out incredible amounts of virus."
Why that occurs is not known, she said, adding, "We're
working on that right now."
Dr. Baldwin said that cocaine had powerful effects on both
the nervous system and the immune system, and that it
caused the body to produce steroid hormones and other
substances that might affect H.I.V. and its ability to
A report on the study will be published in the March issue
of The Journal of Infectious Diseases and is being posted
today on the Internet at
Dr. Warner C. Greene, director of the Gladstone Institute
of Virology and Immunology at the University of California
at San Francisco, who was not involved in the study, said
doctors had wondered why cocaine users had a worse course
"The beauty of this study," Dr. Greene said, "is that it
really focuses in and reveals some specific effect of
cocaine. One clearly sees that cocaine is doing something
to the infection process."
Dr. Greene also said he thought the study would enhance
both doctors' and patients' awareness of cocaine's
potential to accelerate the course of H.I.V. infection.
"I think it has very significant implications for people
infected with H.I.V.," he said.
Dr. Baldwin said that even though the study was done in
mice, she thought the findings would apply to people.
"There's always controversy with animal models," she said.
"But among people who do H.I.V. research, this is an
accepted model. You can't address these questions in a
human population. It would be unethical. This model offers
us something nothing else really can."
Dr. Greene said, "It's a model, but, boy, the effects they
saw were significant."
The mice in the study were inoculated with human cells
because mouse cells do not become infected with H.I.V. The
mice in the study lacked immune systems, and so would not
reject human cells. The mice could then be injected with