 NIMR’s Anne O’Garra on Sorting Out
Cytokines
The immune system is, simply put, the main line of defense against pathogens. It has evolved over the eons to recognize and respond with virtuoso skill to a seemingly infinite array of pathogens, and to do so quickly, efficiently, and—of some importance—without killing the host in the process. Each incoming pathogen challenges the immune system with a series of decisions. First, to respond or not. Then, to tailor the response to that particular invader and no other, and to hit it with just the right amount of force. Too weak a response, and the invader wins the day; too strong, and the host is killed, as well.
The immune system consists of a network of cells that have developed to recognize a wide variety of pathogens, including bacteria, parasites, and viruses. Pathogen-derived products can trigger immune cells to produce cytokines, soluble molecules that promote the immune response. This leads to the destruction or arrest of the infectious organism. However, the immune system is a double-edged sword, since cytokines can also result in damage to the host tissue (for example, in inflammatory diseases)...
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 Middle
Eastern Nations Making Their Mark
In recent years, Iran has substantially increased its presence in world
science, according to papers indexed by Thomson ISI between 1981 and 2002. That’s
just one finding in a new Science Watch survey examining the output and
impact of a selected group of Middle Eastern nations over the last 20 years. As
the graph shows, Iran’s output in science—although still comparatively
small—has rocketed upward in the last decade, more than tripling from the 501
papers indexed in 1996 to a total of 1,830 in 2002...
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