CD22 is a member of the immunoglobulin superfamily, SIGLEC family of lectins. It is first expressed in the cytoplasm of pro-B and pre-B cells, and on the surface as B cells mature to become IgD+. CD22 serves as an adhesion receptor for sialic acid-bearing ligands expressed on erythrocytes and all leukocyte classes. In addition to its potential role as a mediator of intercellular interactions, signal transduction through CD22 can activate B cells and modulate antigen receptor signaling in vitro. The phenotype of CD22-deficient mice suggests that CD22 is primarily involved in the generation of mature B cells within the bone marrow, blood, and marginal zones of lymphoid tissues. CD22 recruits the tyrosine phosphatase Src homology 2 domain-containing phosphatase 1 (SHP-1) to immunoreceptor tyrosine-based inhibitory motifs (ITIMs) and inhibits B-cell receptor (BCR)-induced Ca2+ signaling on normal B cells. CD22 interacts specifically with ligands carrying alpha2-6-linked sialic acids. As an inhibitory coreceptor of the B-cell receptor (BCR), CD22 plays a critical role in establishing signalling thresholds for B-cell activation. Like other coreceptors, the ability of CD22 to modulate B-cell signalling is critically dependent upon its proximity to the BCR, and this in turn is governed by the binding of its extracellular domain to alpha2,6-linked sialic acid ligands. However, genetic studies in mice reveal that some CD22 functions are regulated by ligand binding, whereas other functions are ligand-independent and may only require expression of an intact CD22 cytoplasmic domain at the B-cell surface. CD19 regulates CD22 phosphorylation by augmenting Lyn kinase activity, while CD22 inhibits CD19 phosphorylation via SHP-1.Immune Checkpoint Immunotherapy Cancer Immunotherapy Targeted Therapy
Product Name:
Mouse Siglec-2/CD22 Recombinant Protein (RPES2305)
Product Code:
RPES2305
Size:
50µg
Species:
Mouse
Expressed Host:
HEK293 Cells
Synonyms:
A530093D23,Lyb-8,Lyb8
Accession:
BAE33829.1
Sequence:
Met1-Arg708
Fusion tag:
C-Fc
Endotoxin:
<1.0 EU per µg of the protein as determined by the LAL method.
Protein Construction:
A DNA sequence encoding the mouse CD22 (BAE33829.1)(Met1-Arg708) was expressed with the Fc region of human IgG1 at the C-terminus.
Purity:
> 95 % as determined by SDS-PAGE
Mol Mass:
104.3 kDa
AP Mol Mass:
125 kDa
Formulation:
Lyophilized from sterile PBS, pH 7.4
Shipping:
This product is provided as lyophilized powder which is shipped with ice packs.
Stability and Storage:
Lyophilized proteins are stable for up to 12 months when stored at -20 to -80°C. Reconstituted protein solution can be stored at 4-8°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.