Chemokine ligand 13 (CCL13) is a small cytokine

Cytokine

Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...

 belonging to the CC chemokine

Chemokine

Chemokines are a family of small cytokines, or proteins secreted by cells. Their name is derived from their ability to induce directed chemotaxis in nearby responsive cells; they are chemotactic cytokines...

 family. Its gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

 is located on human chromosome 17 within a large cluster of other CC chemokines. CCL13 induces chemotaxis in monocyte

Monocyte

Monocytes are a type of white blood cell and are part of the innate immune system of vertebrates including all mammals , birds, reptiles, and fish. Monocytes play multiple roles in immune function...

s, eosinophils, T lymphocytes, and basophils by binding cell surface G-protein linked chemokine receptor

Chemokine receptor

Chemokine receptors are cytokine receptors found on the surface of certain cells, which interact with a type of cytokine called a chemokine. There have been 19 distinct chemokine receptors described in mammals...

s such as CCR2, CCR3 and CCR5. Activity of this chemokine has been implicated in allergic reactions such as asthma

Asthma

Asthma is the common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include wheezing, coughing, chest tightness, and shortness of breath...

. CCL13 can be induced by the inflammatory cytokines interleukin-1 and TNF-α.