• Purity

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

• Endotoxin Level

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

• Activity

  Measured by the ability of the immobilized protein to support the adhesion of THP‑1 human acute monocytic leukemia cells. The ED    ₅₀ for this effect is 0.15-0.75 μg/mL.    
     Optimal dilutions should be determined by each laboratory for each application.  

• Source

  Mouse myeloma cell line, NS0-derived

  Met-Asp	Human IgG1 (Pro100-Lys330)	IEGR	Human MCEMP1 (Val106-Gln187) Accession # NP_777578
  N-terminus			C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Met

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  36 kDa (monomer)

• SDS-PAGE

  39-43 kDa, reducing conditions

Background: MCEMP1

MCEMP1 (mast cell‑expressed membrane protein-1), or C19orf59 in humans, is a 22 kDa mast cell specific type II transmembrane protein expressed in lung (1). Human MCEMP1 cDNA encodes 187 amino acids (aa) including an 85 aa N‑terminal cytoplasmic region, a 21 aa transmembrane domain, and an 81 aa C‑terminal extracellular domain (ECD, aa 107‑187) that includes one potential N-glycosylation site. One potential 204 aa splice variant contains a 22 aa substitution for the C‑terminal five amino acids. Within the ECD, human MCEMP1 shares only 36‑44% aa sequence identity with presumed mouse, rat, canine, porcine and bovine MCEMP1 orthologs (1). The 5’ flanking sequence of human MCEMP1 contains motifs for NF kappa B/Rel and NFAT, indicating that MCEMP1 expression may be enhanced by stimuli that also enhance cytokine production, such as allergic reactions or pathogens (2). In addition to lung mast cells, protein expression of MCEMP1 has been identified in cord blood-derived cultured mast cells, the mast cell leukemia cell line HMC-1, the acute monocytic leukemia cell line THP-1, and primary CD14⁺ monocytes and mast cells within or adjacent to lung tumors (1). It is not found on peripheral blood lymphocytes, lymphocytic cell lines, or epithelial cells (1).

• References:

1. Li, K. et al. (2005) Genomics 86:68.

2. Abraham, S.N. et al. (2010) Nat. Rev. Immunol. 10:440.

• Long Name:

  Mast Cell-expressed Membrane Protein 1

• Entrez Gene IDs:

  199675 (Human); 69189 (Mouse); 498128 (Rat)

• Alternate Names:

  C19orf59; chromosome 19 open reading frame 59; mast cell-expressed membrane protein 1; MCEMP1; MGC132456