Growth of AIDS Virus Enhanced by Methamphetamine

Research done on a feline model that mimics human AIDS has shown that exposure to methamphetamine increases by as much as 15-fold the ability of the feline immunodeficiency virus (FIV) to replicate in the cat brain. In the study, which was published in the June 2002 issue of the Journal of NeuroVirolgy, cat brain tissues were exposed to a concentration of methamphetamine equal to the average level in an adult human abuser's bloodstream.

"We found that after about two weeks of chronic methamphetamine exposure, the ability of these infected cell lines to mass-produce virus increases dramatically,” explained Dr. Michael Podell of Ohio State University (Columbus, USA), professor of veterinary clinical sciences and neurosciences.

Before beginning the methamphetamine experiments the investigators established a system for infecting astrocytes isolated from feline brain tissue with the FIV virus. They found that initial infection required that the astrocytes be associated with peripheral blood mononuclear cells (PBMCs). Once it had infected the astrocytes, the virus began to rapidly reproduce, an observation that was contrary to the accepted belief that FIV resulted only in a latent infection.

"We found that the reason the virus multiplies so rapidly is that it mutates into a different strain,” Dr. Podell said, one that is not dependent on the presence of PBMCs. This virus strain appears to be completely independent of any immune system interaction. "That means that any drugs intended to interfere with, or influence the immune system may have absolutely no effect on the astrocyte infection in the brain,” added Dr. Podell. Infection by both virus strains was dependent upon a functional astrocyte CXCR4 receptor.

Methamphetamine significantly increased FIV replication in feline astrocytes for cell-associated infection only, with no effect on peripheral blood mononuclear cells. This viral replication was related to proviral copy number, suggesting that the effect of methamphetamine was at the viral entry or integration into host genome levels, but not at the translational level. Thus, FIV infection of the brain in the presence of methamphetamine resulted in enhanced astrocyte viral replication, producing a more rapid and increased brain viral load.



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