IOWA CITY, Iowa If a person's immune system successfully fights off an infection, not only does that person recover, but they also acquire immunity against re-infection by that same pathogen. The ability of the immune system to remember pathogens it has already defeated, and to respond rapidly and effectively to them during future exposures, is the basis of vaccination strategies.
University of Iowa researchers, led by John Harty, Ph.D., associate professor of microbiology, are making progress in understanding how these complicated aspects of the immune response are controlled. The UI team has found that two molecules, perforin and interferon gamma, already known to participate in the fight against infections, are also responsible for regulating the size and nature of both the initial immune response and the residual protective immunity. The research findings were published in the Nov. 17 issue of the journal Science. The lead author, Vladimir P. Badovinac, Ph.D., and co-author Amy R. Tvinnereim, Ph.D., are both postdoctoral fellows in Harty's lab.
"It was thought that the only role for these molecules was to enable T cells to directly or indirectly destroy infected cells," Harty said. "We have identified another role for the molecules, as regulators that control how many T cells are generated in response to infection and how many of these cells survive and contribute to immune memory."
Harty added that this work reinforces a long-standing notion about the immune system, that it is able to use the same molecule for different functions.
"The immune system has learned to use and modify existing systems to do the jobs required to fight off infections," Harty said.
When an active immune system is confronted by a new foreign invader such as bacteria or a virus, it initially generates large numbers of T cells specific for the infectious agent. These expanded cells undergo a process known as differentiation and become cells that can actively fight
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Contact: Lynn Rose
Lynn-Rose@uiowa.edu
319-335-9585
University of Iowa
15-Nov-2000