July 25, 2008

Spleen Key Player in Brain's Infection-Fighting Messages

FRIDAY, July 25 (HealthDay News) -- New details about how the brain and immune system communicate to fight disease have been discovered by U.S. researchers.

A team at the Feinstein Institute for Medical Research in Manhasset, N.Y., identified a new anatomical path through which the brain and spleen communicate. The spleen, which manufactures immune cells, is also where important information from the nervous system reaches the immune system.

Understanding this process could lead to the development of new treatments that prompt the spleen to send the right messages to the immune system when fighting infections and possibly some autoimmune diseases, the researchers said.

Macrophages in the spleen make tumor necrosis factor (TNF), a powerful inflammation-producing molecule. When the researchers stimulated the vagus nerve -- a long nerve that goes from the base of the brain into thoracic and abdominal organs -- TNF production in the spleen decreased.

The study was published in this week's issue of the Proceedings of the National Academy of Sciences.

Each year in the United States, about 500,000 people develop severe sepsis, and about 225,000 of them die, according to a news release from the Feinstein Institute. Severe sepsis occurs when the immune system reacts much more aggressively than normal to an infection.

The findings suggest that using the central nervous system/spleen connection to control immune response may help improve treatment of sepsis.

More information

The Society of Critical Care Medicine has more about sepsis.

-- Robert Preidt
SOURCE: Feinstein Institute for Medical Research, news release, July 21, 2008
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