Stories tagged HHMI

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Chitin, a clue in understanding asthma.

Asthma linked to chitin: House dust mite.
Asthma linked to chitin: House dust mite.
Chitin is found in dust mites, cockroaches, insect eggs, shellfish, fungi, and intestinal worms. When researchers at Howard Hughes Medical Institute (HHMI) aerosolized purified chitin and sprayed it into the lungs of laboratory mice, it caused a rapid and intense immune response.

The researchers found that when mice have more AMCase than normal, the immune response to chitin is greatly reduced. Locksley believes that AMCase, a chitinolytic enzyme, attenuates the chitin-induced innate immune response by degrading the chitin. This removes the stimulus for further eosinophil and basophil recruitment more rapidly and halts the allergic response. Howard Hughs Medical Institute research news

Acidic mammalian chitinase, AMCase, breaks down chitin.

Our immune system can remember what previous irritants look like and can respond with a customized defense. This ability explains why vaccinations are effective. Sometimes the defense (or allergic response) overwhelms other body functions (like in an asthma attack). Findings about chitin and AMCase may help explain the extremely high rates of asthma—as high as 25 percent—found in previously asymptomatic workers in shellfish processing plants.

Read about new asthma research online.

Richard Locksley's laboratory is investigating the biological mechanisms underlying asthma and hopes to provide new ways of preventing and possibly treating it. The new findings are published in the April 22, 2007, online version of the journal Nature You can read their research abstract here.