• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <0.01 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. When Recombinant Human CRISP‑3 (Catalog # ) is immobilized at 1 µg/mL (100 µL/well), the concentration of Recombinant Human  alpha  1B‑Glycoprotein that produces 50% of the optimal binding response is approximately 0.4‑2.4 ng/mL.

• Source

  Human embryonic kidney cell, HEK293-derived Ala22-Ser495, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Starts at Ala22

• Structure / Form

  Monomer

• Predicted Molecular Mass

  52.8 kDa

• SDS-PAGE

  70-80 kDa, reducing conditions

Background: alpha 1B-Glycoprotein

Alpha-1B-glycoprotein (A1BG) is an approximately 80 kDa molecule that circulates in the serum (1). Mature human A1BG consists of five tandem Ig‑like domains and shares 44% amino acid sequence identity with mouse and rat A1BG (2, 3). Alternative splicing generates an isoform that lacks the signal peptide and the first Ig‑like domain. A1BG binds with high affinity to the cysteine‑rich protein CRISP‑3 (4). In pancreatic carcinoma, it is elevated in pancreatic juice as well as in the serum relative to normal patients (5, 6). A1BG is abnormally excreted into the urine during idiopathic nephrotic syndrome (INS) (7). Multiple breakdown fragments of A1BG are also present in INS urine, including one of 14 kDa that is found in steroid‑resistant but not steroid‑sensitive cases (7). A1BG is also elevated in the urine of patients with interstitial cystitis/painful bladder syndrome (IC/PBS) (8).

• References:

1. Schultze, H.E. et al. (1963) Nature 200:1103.

2. Ishioka, N. et al. (1986) Proc. Natl. Acad. Sci. USA 83:2363.

3. Gardmo, C. et al. (2001) Endocrinology 142:2695.

4. Udby, L. et al. (2004) Biochemistry 43:12877.

5. Tian, M. et al. (2008) BMC Cancer 8:241.

6. Li, C. et al. (2009) J. Proteome Res. 8:483.

7. Piyaphanee, N. et al. (2011) Proteomics Clin. Appl. 5:334.

8. Goo, Y.A. et al. (2010) Int. Braz. J. Urol. 36:464.

• Entrez Gene IDs:

  1 (Human); 117586 (Mouse)

• Alternate Names:

  A1B; A1BG; ABG; alpha 1BGlycoprotein; alpha 1B-Glycoprotein; GAB