The immune system isn’t just about defense; it works in partnership with other cells to regulate body functions.
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A new study shows that immune cells called B cells carry on a three-way conversation with gut microbes and cells lining the intestines to control fat uptake. The finding, reported online November 20 in Nature Medicine, challenges conventional wisdom that the immune system’s only job is to fight bad guys. The new knowledge also may shed some light on why people with HIV and other chronic infections become malnourished, and it might suggest ways to treat malnutrition.
The study grew out of a comment that systems biologist Andrey Morgun, now a researcher at Oregon State University in Corvallis, once heard at an immunology conference. “A speaker mentioned that the immune system isn’t just a war machine,” Morgun says.