CXCL13
Encyclopedia
C-X-C motif chemokine 13 (CXCL13) also known as B lymphocyte chemoattractant (BLC) is a protein
that in humans is encoded by the CXCL13 gene
.
belonging to the CXC chemokine
family. As its name suggests, this chemokine is selectively chemotactic for B cell
s belonging to both the B-1 and B-2 subsets, and elicits its effects by interacting with chemokine receptor
CXCR5
. CXCL13 and its receptor CXCR5 control the organization of B cells within follicles of lymphoid tissues. and is expressed highly in the liver
, spleen
, lymph node
s, and gut
of human
s. The gene
for CXCL13 is located on human chromosome 4 in a cluster of other CXC chemokines.
In T-lymphocytes, CXCL13 expression is thought to reflect a germinal center origin of the T-cell. Hence, expression of CXCL13 in T-cell lymphomas, such as Angioimmunoblastic T-cell Lymphoma, is thought to reflect a germinal center origin of the neoplastic T-cells.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the CXCL13 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...
.
Function
CXCL13 is a small cytokineCytokine
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 CXC 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. As its name suggests, this chemokine is selectively chemotactic for B cell
B cell
B cells are lymphocytes that play a large role in the humoral immune response . The principal functions of B cells are to make antibodies against antigens, perform the role of antigen-presenting cells and eventually develop into memory B cells after activation by antigen interaction...
s belonging to both the B-1 and B-2 subsets, and elicits its effects by interacting with 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...
CXCR5
CXCR5
C-X-C chemokine receptor type 5 also known as Burkitt lymphoma receptor 1 is a G protein-coupled seven transmembrane receptor for chemokine CXCL13 and belongs to the CXC chemokine receptor family...
. CXCL13 and its receptor CXCR5 control the organization of B cells within follicles of lymphoid tissues. and is expressed highly in the liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
, spleen
Spleen
The spleen is an organ found in virtually all vertebrate animals with important roles in regard to red blood cells and the immune system. In humans, it is located in the left upper quadrant of the abdomen. It removes old red blood cells and holds a reserve of blood in case of hemorrhagic shock...
, lymph node
Lymph node
A lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T, and other immune cells. Lymph nodes are found all through the body, and act as...
s, and gut
Gut (zoology)
In zoology, the gut, also known as the alimentary canal or alimentary tract, is a tube by which bilaterian animals transfer food to the digestion organs. In large bilaterians the gut generally also has an exit, the anus, by which the animal disposes of solid wastes...
of human
Human
Humans are the only living species in the Homo genus...
s. The 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...
for CXCL13 is located on human chromosome 4 in a cluster of other CXC chemokines.
In T-lymphocytes, CXCL13 expression is thought to reflect a germinal center origin of the T-cell. Hence, expression of CXCL13 in T-cell lymphomas, such as Angioimmunoblastic T-cell Lymphoma, is thought to reflect a germinal center origin of the neoplastic T-cells.