CD19 protein is a 95 kDa transmembrane glycoprotein that plays a central role in B cell activation and humoral immune responses. Within the ECD, human CD19 shares 57% amino acid sequence identity with mouse and rat CD19. It is required for the responsiveness of mature B cell to antigen stimulation, germinal center development, and antibody affinity maturation. CD19 polymorphisms and up-regulation can lead to the development of autoimmunity by promoting autoantibody production. CD19 has emerged as promising therapeutic target for hematologic cancers and solid tumors. Immunotherapy using a chimeric antigen receptor (CAR) targeting CD19 has proven effective in many different cancers. Specifications Synonyms CD19, B4, CVID3, Leu-12, MGC12802 Uniprot No. P15391-1 Source Recombinant Human CD19 Protein is expressed from HEK293 Cells with His tag at the C-terminal. It contains Pro20-Lys291. Molecular Weight Approximately 34.7 kDa. Due to glycosylation, the protein migrates to 50-60 kDa based on Tris-Bis PAGE result. Physical Appearance Sterile Filtered White lyophilized (freeze-dried) powder. Purity > 95% as determined by SDS-PAGE Activity ELISA Data: Immobilized Human CD19 Protein at 5 μg/mL can bind different Anti-CD19 Antibodies with high affinity. Endotoxin < 1.0 EU per 1μg of the protein by the LAL method. Formulation Lyophilized from 0.22 μm filtered solution in PBS (pH 7.4). Normally 5% trehalose is added as protectant before lyophilization. Reconstitution Centrifuge tubes before opening. Reconstituting to a concentration more than 100 μg/mL` is recommended (usually we use 1 mg/mL solution for lyophilization). Dissolve the lyophilized protein in distilled water. Storage The product should be stored at -20~-80℃ for 1 year from date of receipt. 2-7 days, 2 ~8 °C under sterile conditions after reconstitution. 3-6 months, -20~-80℃ under sterile conditions after reconstitution. Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles. Note 1. Avoid repeated freezing and thawing. 2. Please operate with lab coats and disposable gloves, for your safety. 3. This product is for research use only. Product Data
