BAFF Protein - NEW


AnaSpec is pleased to announce the release of a recombinant human BAFF protein. Nave B-cells treated with 20-1000 ng/ml BAFF protein prepared by AnaSpec shows increased IgG secretion compared to 2 leading commercial sources (Figure 1).

BAFF (BlyS, TALL-1, THANK, TNFSF13B, zTNF4) belongs to the TNF superfamily of proteins and is expressed by myeloid cells.1-4 It is a 285-amino acid long type II transmembrane protein, with the soluble152-amino acid active region. 1-4 BAFF plays a pivotal role in B-cells homeostasis including survival of immature B-cells, transition of B-lymphocytes from T1 to T2 stage, and causes increase of antibodies secretion by B-cells. 1-4

The sequence (Accession # NP_006564) corresponding to the extracellular domain of human BAFF along with a 6x His tag was expressed in E. coli. Recombinant human BAFF was purified from urea denatured bacterial lysate using immobilized metal affinity chromatography (IMAC) and refolded into its active state using a proprietary technique. The molecular weight of the recombinant human BAFF is 17.2 kDa (Figure 2). Containing less than 0.1 EU of endotoxin per 1 μg of protein as determined by LAL assay, the activity of BAFF was determined by its ability to stimulate production of immunoglobulin molecules such as IgG, IgA, and IgM in isolated mouse B-lymphocytes (Figure 1). Purified recombinant human BAFF is supplied as sterile and frozen condition at 0.1 mg/ml in 1 x PBS buffer with 5 mM DTT, pH=7.5.

Figure 1. Purified nave B-lymphocytes were isolated from mouse spleen, pre-treated with CpG ODN 1555, and stimulated with increasing concentration of Human BAFF followed by IgG concentration measurement.LPS+IL-4 treated B-cells is the positive control and 0 the negative control.



Figure 2.
Recombinant human BAFF on 10-20% Tris-HCl SDS-PAGE. MWM=molecular weight marker, CL=cell lysate before column coupling, FT=flow through after coupling, P=purified and refolded recombinant human BAFF.

References:

  1. Batten, M. et. al. (2000) J Exp Med 192 (10): 1453-1465
  2. Parry, TJ. et. al. (2001) J Pharm Exp Ther 296 (2): 396-404
  3. Shan, X. et. al. (2006) Physiol Res 55: 301-307
  4. Katsenelson, N. et. al. (2007) Eur J Immunol 37: 1785-1795