chemokine (C-X-C motif) ligand 13 (CXCL13), also known as B lymphocyte chemoattractant (BLC) or B cell-attracting chemokine 1 (BCA-1), is a protein ligand that in humans is encoded by the CXCL13 gene.  
Function [ edit ]
CXCL13 is a small
cytokine belonging to the CXC chemokine family. As its name suggests, this chemokine is selectively chemotactic for B cells 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 nodes, and gut of humans. 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, particularly a subset of T cells called
follicular B helper T cells (or T FH cells). 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. 
References [ edit ]
^ "Human PubMed Reference:".
^ "Mouse PubMed Reference:".
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