Some people who suffer from asthma have a frustrating, but essentially treatable condition, while others can endure life-threatening asthma attacks. Now scientists say they may know why. A protein called IL-17A appears to be triggered by exposure to common allergens such as pollen, dust, pet dander, and mold, and can build up in the system, causing a severe asthma reaction. Researchers say the study was conducted in mice but has implications for the treatment of human asthma.

Source: http://www.healthcentral.com/allergy/news-534479-98.html