Immune system


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Immune system


The immune system is the body's natural defense system that helps fight infections. The immune system is made up of antibodies, white blood cells, and other chemicals and proteins that attack and destroy substances such as bacteria and viruses that they recognize as foreign and different from the body's normal healthy tissues.

The immune system is also responsible for allergic reactions and allergies, which may occur when the immune system incorrectly identifies a substance (allergen), such as pollen, mold, chemicals, plants, and medications, as harmful.

Sometimes the immune system also mistakenly attacks the body's own cells, which is known as an autoimmune disease.

Credits


Author Jeannette Curtis
Author Caroline Rea, RN, BS, MS
Editor Kathleen M. Ariss, MS
Editor Susan Van Houten, RN, BSN, MBA
Associate Editor Tracy Landauer
Associate Editor Pat Truman, MATC
Primary Medical Reviewer Patrice Burgess, MD - Family Medicine
Primary Medical Reviewer Adam Husney, MD - Family Medicine
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Last Updated May 25, 2007

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Last updated: May 25, 2007
Author: Caroline Rea, RN, BS, MS
Reviewed By: Kathleen Romito, MD - Family Medicine
Editors: Susan Van Houten, RN, BSN, MBA, Pat Truman, MATC

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