MedicalTerminology DB

Meaning of interleukin-1: One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

Definition of interleukin-1

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body. Interleukin-1 is made mainly by one type of white blood cell, the macrophage, and helps another type of white blood cell, the lymphocyte, fight infections. It also helps leukocytes pass through blood vessel walls to sites of infection and causes fever by affecting areas of the brain that control body temperature. There are two forms of interleukin-1, alpha and beta, which act the same. Interleukin-1 made in the laboratory is used as a biological response modifier to boost the immune system in cancer therapy. Interleukin-1 is a type of cytokine. Also called IL-1.

Written and maintained by James Murray Last updated July 21, 2026 Educational reference, not medical advice. Read the limitations.

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.