Biotinylated Human CD19 (20-291), Fc Tag, Avi Tag (CD9-H82F7) is expressed from human 293 cells (HEK293). It contains AA Pro 20 - Lys 291 (Accession # P15391-1).
Predicted N-terminus: Pro 20
This protein carries a human IgG1 Fc tag at the C-terminus, followed by a Avi tag (Avitag™).
The protein has a calculated MW of 58.9 kDa. The protein migrates as 70 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.
Biotinylation of this product is performed using Avitag™ technology. Briefly, the single lysine residue in the Avitag is enzymatically labeled with biotin.
The biotin to protein ratio is 0.5-1 as determined by the HABA assay.
Less than 1.0 EU per μg by the LAL method.
>95% as determined by SDS-PAGE.
Lyophilized from 0.22 μm filtered solution in Tris with Glycine, Arginine and NaCl, pH7.5. Normally trehalose is added as protectant before lyophilization.
Contact us for customized product form or formulation.
Please see Certificate of Analysis for specific instructions.
For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
No activity loss was observed after storage at:
- 4-8°C for 12 months in lyophilized state;
- -70°C for 3 months under sterile conditions after reconstitution.
Biotinylated Human CD19 (20-291), Fc Tag, Avi Tag on SDS-PAGE under reducing (R) condition. The gel was stained overnight with Coomassie Blue. The purity of the protein is greater than 95%.
CAR阳性表达率检测（Evaluation of CAR expression ）
FACS Analysis of anti-CD19 CAR Expression
Biotinylated Human CD19 (20-291), Fc Tag, Avi Tag (Cat. No. CD9-H82F7) binding 293-CAR cells transfected with Anti-CD19-scFv and RFP tag 293-CAR cell is the stable cell line transfected with Anti-CD19-scFv and RFP tag. 2x105 of the cells were incubated with the test proteins respectively, washed and then followed by FITC-SA and analyzed with FACS. RFP was used to evaluate CAR (Anti-CD19-scFv) expression and FITC signals was used to evaluate the binding activity.
B-lymphocyte antigen CD19 is also known as CD19 (Cluster of Differentiation 19), is a single-pass type I membrane protein which contains two Ig-like C2-type (immunoglobulin-like) domains. CD19 is expressed on follicular dendritic cells and B cells. In fact, it is present on B cells from earliest recognizable B-lineage cells during development to B-cell blasts but is lost on maturation to plasma cells. It primarily acts as a B cell co-receptor in conjunction with CD21 and CD81. Upon activation, the cytoplasmic tail of CD19 becomes phosphorylated, which leads to binding by Src-family kinases and recruitment of PI-3 kinase. As on T cells, several surface molecules form the antigen receptor and form a complex on B lymphocytes. The (almost) B cell-specific CD19 phosphoglycoprotein is one of these molecules. The others are CD21 and CD81. These surface immunoglobulin (sIg)-associated molecules facilitate signal transduction. On living B cells, anti-immunoglobulin antibody mimicking exogenous antigen causes CD19 to bind to sIg and internalize with it. The reverse process has not been demonstrated, suggesting that formation of this receptor complex is antigen-induced. This molecular association has been confirmed by chemical studies. Mutations in CD19 are associated with severe immunodeficiency syndromes characterized by diminished antibody production. CD19 has been shown to interact with: CD81, CD82, Complement receptor 2, and VAV2.