October 2, 2001 (Cox News Service) - Harvard Medical School researchers have identified a gene in mice that confers resistance to anthrax, an often fatal disease that might be used as a biological weapon in terrorist attacks.
The research, published Monday in the October issue of the journal Current Biology, could point the way to a possible human defense against the bacterium. The gene also exists in a different form in humans; it isn't known if the human forms create immunity in the way the mouse gene appears to.
Dr. William F. Dietrich and other researchers found that variations in the mouse gene, which is called Kif1C, alter the body's vulnerability to anthrax, essentially by keeping the immune response in check.
In most cases of infection, the body mobilizes immune cells to surround and digest invading bacteria. Anthrax bacteria, though, produce a toxin that sends one class of immune cells called macrophages into overdrive. The macrophages overreact, self-destructing and releasing other toxins into the bloodstream; that release of toxins sends the system into shock, which kills the infected person.
Two variants of the gene, though, appeared to protect cells from the self-destruction triggered by anthrax toxin. Researchers aren't yet sure why, though they theorize it may be connected to a protein made by the gene that ferries repair material around inside cells; if the protein helped sequester the anthrax toxin in one part of a cell, it might reduce the overall damage.
If the human gene works the same way, its action could potentially be strengthened; at the least, it could be used to identify individuals at lower risk, the scientists said. At the moment, protection against anthrax lies only in a vaccine that is in such short supply it cannot be obtained by civilians, or in doses of antibiotics that must be taken immediately after exposure.
Copyright 2001 Cox News Service. All rights reserved.
