Product Specifications for Recombinant Human CD19 Protein, Atto 488 Conjugate
Chinese Hamster Ovary cell line, CHO-derived human CD19 protein
Human CD19 (Glu21-Lys291) Accession # P15391
Human IgG1 (Pro100-Lys330)
>90%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
<1.0 EU per 1 μg of the protein by the LAL method.
N-terminal sequence Analysis
Predicted Molecular Mass
77-92 kDa, under reducing conditions
Measured by flow cytometry for its ability to bind anti-Human CD19 Monoclonal Antibody conjugated fluorescent beads.
Scientific Data Examples for Recombinant Human CD19 Protein, Atto 488 Conjugate
Detection of CD19 construct on human CART cells
Human PBMC CD4+ and CD8+ T cells were either (A) transduced or (B) not transduced (negative control) with a Human CD19 CAR and then cultured for 11 days. Cells were washed twice with 2mL 1x PBS then stained with a viability dye for 15-30 min at room temp in the dark. Human block (1-001-A) was added during the viability stain to block Fc receptors. Cells were washed twice with Flow Cytometry Staining Buffer (FC001) then stained with Human CD4 PE-Cy7-conjugated Antibody and rhCD19 Atto 488-conjugated protein (ATJ9269) for 25 min at room temp in the dark. Staining was performed using our staining membrane proteins protocol.
Recombinant Human CD19 Protein, Atto 488 Conjugate SDS-PAGE.
2 μg/lane of Recombinant Human CD19 Fc Chimera Atto 488 (ATJ9269) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 77-92 kD and 154-184 kDa, respectively.
Formulation, Preparation and Storage
What does CF mean?
CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our
Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant
protein to be stored at a more dilute concentration.
The carrier free version does not contain BSA.
Supplied as a 0.2 μm filtered solution in PBS with BSA as a carrier protein.
The product is shipped with dry ice or equivalent. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage:
Protect from light. Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
6 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after opening.
3 months, -20 to -70 °C under sterile conditions after opening.
CD19 is a 95 kDa transmembrane glycoprotein that plays a central role in B cell activation and humoral immune responses (1, 2). Mature human CD19 consists of a 272 amino acid (aa) extracellular domain (ECD) with two Ig-like domains, a 22 aa transmembrane segment, and a 243 aa cytoplasmic domain (3). Within the ECD, human CD19 shares 57% amino acid sequence identity with mouse and rat CD19. CD19 is expressed throughout B cell development from pre-B cells to mature B cells, and it is commonly used as a B cell lineage marker (1). It is required for the responsiveness of mature B cell to antigen stimulation, germinal center development, and antibody affinity maturation (4, 5). CD19 associates with the B cell antigen receptor (BCR), CD81, CD38, CD21, CD22, and IFITM1/CD225/Leu13, (6-9). These associations enable CD19 to amplify B cell signaling (7, 9-12) and reduce the threshold for antigen stimulation through the BCR (13). CD19 polymorphisms and up-regulation can lead to the development of autoimmunity by promoting autoantibody production (2).
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