Small signaling proteins cells use to send immune and inflammation messages.

Cytokines are messenger molecules that help cells coordinate immune responses, inflammation, and tissue repair. They are normal and necessary in the body, but chronically elevated inflammatory cytokines can be a sign that something is wrong.

In aging research, cytokines often come up because senescent cells can release them as part of SASP.

Cytokines are not automatically harmful. Context matters. Short-term immune signaling is different from chronic, low-grade inflammatory signaling.

Research publication: Definitions reflect current research status and are for educational purposes. This is not medical advice.