• Purity

  >95%, by SDS-PAGE with silver staining

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. When Recombinant Mouse Mesothelin is immobilized at 2 μg/mL (100 μL/well), the concentration of Recombinant Human CA125/MUC16 (Catalog # ) that produces 50% optimal binding response is approximately 0.4-2.4 ng/mL.

• Source

  Chinese Hamster Ovary cell line, CHO-derived Asp298-Ser600, with a C-terminal 6-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  Asp298

• Predicted Molecular Mass

  35 kDa

• SDS-PAGE

  38-55 kDa, reducing conditions

Background: Mesothelin

Mesothelin, also known as CAK1 and ERC, is derived from a 70 kDa precursor that also includes Megakaryocyte Potentiating Factor (MPF) (1-3). The 70 kDa precursor is expressed on the cell surface where it is cleaved at a dibasic proteolytic site to release the 32 kDa glycosylated MPF (3, 4). MPF is a cytokine that potentiates IL-3 induced megakaryocyte colony formation (2, 5). The term Mesothelin refers to the 40 kDa glycosylated protein which remains attached to the cell surface   via a GPI linkage. Mesothelin is normally expressed on mesothelial cells in the pleura, pericardium, and peritoneum as well as in the developing and postnatal pancreas (1, 6). It is up-regulated in mesotheliomas and a range of carcinomas and adenomas (7-10). Mesothelin promotes tumor cell proliferation, migration, anchorage-independent growth, and tumor progression, in part through the up-regulation of MMP-7 (9, 11, 12). It is co-expressed with the tumor antigen CA125/MUC16 on advanced ovarian adenocarcinomas and interacts with this molecule to support cell adhesion (13). A soluble form of Mesothelin, with its GPI anchor intact, is released from tumor cells and binds to MMR/CD206 on macrophages (10, 14-16).

• References:

1. Hassan, R. et al. (2004) Clin. Cancer Res. 10:3937.

2. Kojima, T. et al. (1995) J. Biol. Chem. 270:21984.

3. Chang, K. and I. Pastan (1996) Proc. Natl. Acad. Sci. 93:136.

4. Onda, M. et al. (2006) Clin. Cancer Res. 12:4225.

5. Yamaguchi, N. et al. (1994) J. Biol. Chem. 269:805.

6. Hou, L.-Q. et al. (2008) Develop. Growth Differ. 50:531.

7. Ordonez, N.G. (2003) Mod. Pathol. 16:192.

8. Argani, P. et al. (2001) Clin. Cancer Res. 7:3862.

9. Li, M. et al. (2008) Mol. Cancer Ther. 7:286.

10. Scholler, N. et al. (1999) Proc. Natl. Acad. Sci. 96:11531.

11. Uehara, N. et al. (2008) Mol. Cancer Res. 6:186.

12. Chang, M.-C. et al. (2012) Biochem. J. 442:293.

13. Rump, A. et al. (2004) J. Biol. Chem. 279:9190.

14. Ho, M. and M.O. Lively (2006) Cancer Epidemiol. Biomarkers Prev. 15:1751.

15. Robinson, B.W.S. et al. (2003) Lancet 362:1612.

16. Dangaj, D. et al. (2011) PLoS ONE 6:e28386.

• Entrez Gene IDs:

  10232 (Human); 56047 (Mouse); 60333 (Rat)

• Alternate Names:

  CAK1 antigen; CAK1; megakaryocyte potentiating factor; Mesothelin; MPF; MPFSMRP; MSLN; Pre-pro-megakaryocyte-potentiating factor; SMR; soluble MPF mesothelin related protein