What Is the Function of the Immune System?

The immune system is a combination of many different cells in the body that work together to protect it from infections and tumors. Red blood cells, platelets, killer cells and B cells all originate in the bone marrow and migrate throughout the body.

Thymus Gland

Cells that migrate to the thymus gland are turned into T cells, which act as signals to other immune-related cells when they are needed.

Spleen

The spleen acts as a filter for the blood. Most all the immune cells travel through the spleen at some point, and old red blood cells are destroyed in this organ.

Lymph Nodes

Other body fluids travel through the lymph nodes for cleaning. Antigens are filtered from these fluids in the lymph nodes, and clean fluids are passed on through to the rest of the body.

Attacks

Made from the immune cells, antibodies attack bacteria and infection, triggering the production of more killer cells until the threat is removed.

Stress

According to the American Psychological Association, stress can create artificial responses that confuse and depress the immune system, leading to a higher risk of disease and infection.

Resources

• American Psychological Association