"Dual key" activation, in which two people must act in concert to launch a weapon, is often installed to safeguard highly destructive arms. New research at the Weizmann Institute of Science shows that cells may employ this strategy as well before launching certain potent weapons of the immune system.
Interferons, which were discovered 50 years ago, are the body's first line of defense against viral attack. They are produced in cells that have been invaded by viruses, and from there they spread out to warn other cells to prepare for the impending onslaught. These signaling molecules are associated with the symptoms fever and inflammation of viral infections such as the flu. Three main interferon families have been identified, and they are known by the Greek letters alpha, beta, and gamma. Interferons alpha and beta are very similar: they have nearly identical modes of action and even attach to the same receptor on the cell wall. However, interferon gamma is different. It has its own receptor and, in addition to its immediate antiviral actions, is involved in a number of crucial activities in the immune system, including a step known as antigen presenting, which enables the immune system to tailor antibodies to a specific enemy, and the activation of certain immune cells that engulf and destroy pathogens.
But new findings published recently in the Proceedings of the National Academy of Sciences (PNAS) show that the third type of interferon often doesn't act alone. The Weizmann Institute team, headed by Prof. Menachem Rubinstein of the Molecular Genetics Department and including Drs. Vladimir Hurgin, Daniela Novick, and Ariel Werman, together with Prof. Charles Dinarello of the University of Colorado, found that another molecule produced inside cells interleukin-1 alpha (IL-1 alpha) must be present for initiating many of the basic activities of interferon gamma.
While molecules have been known to work together in this way, the colla
Contact: Jennifer Manning
American Committee for the Weizmann Institute of Science