Search over 1.4 million articles by over 600 experts
  1. Home
  2. Health
  3. Asthma

More from About.com

Browse Topics A-Z

"Immune System"

By Kathleen MacNaughton, R.N., About.com

Updated: February 28, 2008

About.com Health's Disease and Condition content is reviewed by Sanja Jelic, MD

Definition: Your immune system is a set of cells and proteins that work together to protect your body from substances that are seen as threats, such as bacteria and viruses.

The immune system does a lot of good in keeping you healthy. However, in people who have allergies and asthma, the immune system treats pollens and other triggers – which are not normally harmful – as threats and produces an overreaction in the body.

The result is asthma symptoms, such as wheezing, coughing, chest tightness, and shortness of breath.

Pronunciation: ihm-YOUN SYS-tem

Examples: Whenever Judy would pet her sister's cat, her immune system would kick into gear and before she knew it, she was sneezing and wheezing.

About.com is accredited by the Health On the Net Foundation, which promotes reliable and trusted online health information.
  1. Home
  2. Health
  3. Asthma
  4. Asthma Basics
  5. Asthma Glossary
  6. Immune System

©2008 About.com, a part of The New York Times Company.

All rights reserved.