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Antigen

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An antigen is a substance (such as part of a virus or bacteria) that triggers the immune system to produce cells (antibodies) that attack and try to destroy the antigen. The body usually produces one specific type of antibody for each antigen.

Sometimes the body mistakenly recognizes its own tissue as an antigen or foreign substance and produces antibodies against its own tissue. This is called an autoimmune response or autoimmune disease.

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

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