Recombinant Human CXCL13, BCA-1

Stable at 2-4C, but best kept desiccated -20C. Upon reconstitution, stable for up to 1 week at 2-8C. For longer term, divide into working aliquots and store at -20C to -80C. Avoid repeated freeze/thaw cycles.

BCA-1/BLC/CXCL13, also known as B-lymphocyte chemoattractant (BLC), is a CXC chemokine that is constitutively expressed in secondary lymphoid organs. BCA-1 cDNA encodes a protein of 109 amino acid residues with a leader sequence of 22 residues. Mature human BCA-1 shares 64% amino acid sequence similarity with the mouse protein and 23-34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA-1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkittfs lymphoma cells, has now been shown to be the specific receptor for BCA-1. Among cells of the hematopoietic lineages, the expression of BLR1, now designated CXCR5, is restricted to B lymphocytes and a subpopulation of T helper memory cells. Mice lacking BLR1 have been shown to lack inguinal lymph nodes. These mice were also found to have impaired development of Peyerfs patches and defective formation of primary follicles and germinal centers in the spleen as a result of the inability of B lymphocytes to migrate into B cell areas. The protein is a single, non-glycosylated polypeptide chain containing 87 amino acids.

Centrifuge vial prior to opening. Add sterile distilled water or aqueous buffer to a concentration of 0.1-1.0 mg/mL. Further dilutions should be made in appropriate buffered solutions.

Fully biologically active compared to standard. The ED50 by a chemotaxis bioassay using human CXCR5 transfected BaF3 mouse proB cells is <20 ng/ml.