Recombinant Human BCA-1 (CXCL13)

The homeostatic chemokine CXCL13 is constitutively expressed in secondary lymphoid tissue and known to initiate lymphoid neogenesis when expressed aberrantly in mice. CXCL13 has also been detected in chronic inflammation associated with human lymphoid neogenesis, suggesting a pathogenic role. Follicular dendritic cells are generally considered to be the major source of CXCL13 both in normal and aberrant lymphoid tissue. CXCL13 has been the exclusive ligand for CXCR5, which initiates chemotaxis toward an increasing gradient in vitro and to B cell zones in lymph nodes that express CXCL13. More recently, CXCR5 expression has also been shown in DN T cells in mice, a subset of CD4 follicular Th cells, and some tonsillar CD4+ and CD25+ Tregs in humans.