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URL of this page: //medlineplus.gov/ency/imagepages/8932.htm
Immune system structures
Overview
The immune system protects the body from potentially harmful substances. The inflammatory response (inflammation) is part of innate immunity. It occurs when tissues are injured by bacteria, trauma, toxins, heat or any other cause.
Review Date 2/13/2026
Updated by: Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
