Paracrine function

Definition

Paracrine function describes the action of signaling molecules released by cells that affect nearby target cells within a localized area. This type of signaling is crucial for coordinating cellular responses in immune functions.

5 Must Know Facts For Your Next Test

1. Paracrine signaling involves the release of cytokines and chemokines that act on nearby cells to modulate immune responses.
2. In innate nonspecific host defenses, paracrine signals help recruit immune cells to the site of infection or injury.
3. Examples of paracrine factors include interferons, which are released by virus-infected cells to inhibit viral replication in neighboring cells.
4. Paracrine signaling is short-lived because the signaling molecules are quickly degraded or immobilized.
5. Unlike endocrine signals, paracrine signals do not travel through the bloodstream but diffuse through extracellular fluid.

Related terms

Cytokine: Small proteins important in cell signaling, especially in immune responses.

Chemokine: A type of cytokine that specifically induces chemotaxis in nearby responsive cells.

Endocrine Function: Signaling involving hormones released into the bloodstream to affect distant target organs or tissues.