Immune system
Disease Information
In-Depth
How does a healthy immune system work?
The organs involved with the immune system are called the lymphoid organs; they include adnoids, blood vessels, bone marrow, lymph nodes, lymphatic vessels, the spleen, and the tonsils. Lymphoid organs affect growth, development, and the release of lymphocytes (a certain type of infection-fighting white blood cell which is vital to an effective immune system).
What are some disorders of the immune system?
Diseases can occur when the immune system doesn’t function properly. Allergies and hypersensitivity to certain substances are considered immune system disorders. So are:
- Autoimmune diseases, such as juvenile diabetes, rheumatoid arthritis, and anemia
- Immunodeficiency diseases, such as AIDS and severe combined immunodeficiency (SCID).


