A coordinated reaction of the immune system to a recognized foreign substance, infectious agent, abnormal cell, or other target.
An immune response involves interactions among immune cells, antibodies, signaling molecules, and other components of the immune system. It can help identify and eliminate infectious agents, remove damaged or abnormal cells, and establish immunological memory.
Immune responses can be innate, providing rapid and broadly directed defense, or adaptive, involving more specific responses by lymphocytes and antibodies. An immune response is not always beneficial; excessive or misdirected responses can contribute to allergies, autoimmune disease, and tissue damage.
QUICK FACT
The immune response is not synonymous with inflammation. Inflammation can be part of an immune response, but immune responses can occur without the classic features of inflammation.
COMMONLY CONFUSED WITH
- Immunity: the body’s overall ability to recognize and defend against harmful agents; an immune response is an active reaction that contributes to that protection.
- Inflammation: a tissue response involving vascular and cellular changes that can occur as part of an immune response.
SEE ALSO