分子别名（Synonym）
CD33,SIGLEC3,gp67
表达区间及表达系统（Source）
Biotinylated Human Siglec-3, Avitag,His Tag (CD3-H82E7) is expressed from human 293 cells (HEK293). It contains AA Asp 18 - His 259 (Accession # AAH28152.1).
Predicted N-terminus: Asp 18
蛋白结构（Molecular Characterization）
This protein carries an Avi tag (Avitag™) at the C-terminus, followed by a polyhistidine tag.
The protein has a calculated MW of 29.4 kDa. The protein migrates as 45-55 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.
标记（Biotinylation）
Biotinylation of this product is performed using Avitag™ technology. Briefly, the single lysine residue in the Avitag is enzymatically labeled with biotin.
蛋白标记度（Biotin:Protein Ratio)
The biotin to protein ratio is 0.5-1 as determined by the HABA assay.
内毒素（Endotoxin）
Less than 1.0 EU per μg by the LAL method.
纯度（Purity）
>90% as determined by reduced SDS-PAGE.
>90% as determined by SEC-MALS.
制剂（Formulation）
Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. Normally trehalose is added as protectant before lyophilization.
Contact us for customized product form or formulation.
重构方法（Reconstitution）
Please see Certificate of Analysis for specific instructions.
For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.
存储（Storage）
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
This product is stable after storage at:
- -20°C to -70°C for 12 months in lyophilized state;
- -70°C for 3 months under sterile conditions after reconstitution.
电泳（SDS-PAGE）
Biotinylated Human Siglec-3, Avitag,His Tag on SDS-PAGE under reducing (R) condition. The gel was stained overnight with Coomassie Blue. The purity of the protein is greater than 90%.
SEC-MALS
The purity of Biotinylated Human Siglec-3, Avitag,His Tag (Cat. No. CD3-H82E7) was more than 90% and the molecular weight of this protein is around 70-80 kDa verified by SEC-MALS.
Report
活性（Bioactivity）-ELISA
Immobilized anti human CD33 MAb, Mouse IgG1 (Clone # 6C5/2) at 2 μg/mL (100 μL/well) can bind Biotinylated Human Siglec-3, Avitag,His Tag (Cat. No. CD3-H82E7) with a linear range of 0.078-2.5 ng/mL (QC tested).
Protocol
背景（Background）
Myeloid cell surface antigen CD33 is also known as SIGLEC3, Siglecs (sialic acid binding Iglike lectins) and GP67, is a single-pass type I membrane protein which belongs to the immunoglobulin superfamily and SIGLEC (sialic acid binding Ig-like lectin) family. Human CD33 / Siglec-3 cDNA encodes a 364 amino acid (aa) polypeptide with a hydrophobic signal peptide, an N-terminal Ig-like V-type domain, one Ig-like C2-type domains, a transmembrane region and a cytoplasmic tail. CD33 / Siglec-3 usually considered myeloid-specific, but it can also be found on some lymphoid cells. In the immune response, CD33 / Siglec-3 may act as an inhibitory receptor upon ligand induced tyrosine phosphorylation by recruiting cytoplasmic phosphatase(s) via their SH2 domain(s) that block signal transduction through dephosphorylation of signaling molecules. CD33 / Siglec-3 induces apoptosis in acute myeloid leukemia.
