• Species Reactivity

  Human

• Specificity

  Detects human Siglec-2 in direct ELISAs. In direct ELISAs, no cross-reactivity with recombinant human Siglec-3, -5, -7, -9, -10, -F, or recombinant mouse Siglec‑11 is observed.

• Source

  Monoclonal Mouse IgG1 Clone # 219934

• Immunogen

  Mouse myeloma cell line NS0-derived recombinant human Siglec-2/CD22    
  Asp20-Arg687    
  Accession # CAA42006

• Formulation

  Supplied 0.2 mg/mL in a saline solution containing BSA and Sodium Azide.

• Label

  Alexa Fluor 647

Applications

• Recommended    
  Concentration

  Sample

• Flow Cytometry

  0.25-1 µg/10    ⁶ cells

  Human peripheral blood mononuclear cells (PBMCs)

• 
  

Please Note: Optimal dilutions should be determined by each laboratory for each application.  are available in the Technical Information section on our website.

Preparation and Storage

• Shipping

  The product is shipped with polar packs. Upon receipt, store it immediately at the temperature recommended below.

• Stability & Storage

  Store the unopened product at 2 - 8 °C. Do not use past expiration date.

Background: Siglec-2/CD22

Siglecs (Sialic acid binding Ig-like Lectins) are I-type (Ig-type) lectins belonging to the Ig superfamily. They are characterized by an N-terminal V-type Ig-like domain which mediates sialic acid binding, followed by varying numbers of C2-type Ig-like domains (1, 2). Fourteen human Siglecs have been cloned and characterized. They are Sialoadhesin/CD169/Siglec-1, CD22/Siglec-2, CD33/Siglec-3, Myelin-Associated Glycoprotein (MAG/Siglec-4a), and the identified Siglecs 5 to 11, plus 14 to 16 (1-3). To date, no Siglec has been shown to recognize any cell surface ligand other than sialic acid, suggesting that interactions with glycans containing this carbohydrate are important in mediating the biological functions of Siglecs. Human Siglec-2, also known as B-cell antigen CD22 or B lymphocyte cell adhesion molecule (BL-CAM), is a B cell restricted glycoprotein that is expressed in the cytoplasm of progenitor B and pre-B cells and on the surface of mature B cells and intestinal eosinophils (3,4). Two distinct human Siglec-2/CD22 cDNAs that arise from differential RNA processing of the same gene have been isolated. The predominant Siglec-2/CD22 beta encodes an 847 amino acid (aa) polypeptide with a hydrophobic signal peptide, an V-type N-terminal Ig-like domain, six C2-type Ig-like domains, a transmembrane region and a cytoplasmic tail with 4 immunoreceptor tyrosine-based inhibition motifs (ITIMs) (5). The variant Siglec-2/CD22 alpha encodes a 647 aa polypeptide missing two C2-type Ig-like domains and has a truncated (23 aa) cytoplasmic tail (6). Siglec-2/CD22 is an adhesion molecule that preferentially binds alpha 2,6- linked sialic acid on the same (cis) or adjacent (trans) cells. Besides its role as an adhesion molecule, Siglec-2/CD22 is a coreceptor that physically interacts with B cell receptor (BCR) and is rapidly phosphorylated upon BCR ligation (3). It negatively regulates BCR signals by recruiting tyrosine phosphatase SHP-1 to its ITIMs, likely within large oligomeric complexes. Over aa 20-687, human and mouse share 59% aa sequence identity.

• References:

1. Magesh, S. et al. (2011) Curr. Med. Chem. 18:3537.

2. Bocher, B.S.. and N. Zimmermann (2015) J. Allergy Clin. Immunol. 135:598.

3. Nitschke, L. (2014) Glycobiology 24:807.

4. Wen, T. et al. (2012) J. Immunol. 188:1075.

5. Wilson, G.L et al. (1991) J. Exp. Med. 173:137.

6. Stamenkovic, I. and B. Seed (1990) Nature 345:74.

• Long Name:

  Sialic Acid Binding Ig-like Lectin 2

• Entrez Gene IDs:

  933 (Human); 12483 (Mouse)

• Alternate Names:

  B-cell receptor CD22; BL-CAM; B-lymphocyte cell adhesion molecule; CD22 antigenMGC130020; CD22 molecule; CD22; sialic acid binding Ig-like lectin 2; Sialic acid-binding Ig-like lectin 2; Siglec2; Siglec-2; SIGLEC2FLJ22814; T-cell surface antigen Leu-14