Anti-CD19 & Anti-CD3e Bispecific Antibody (scFv), Biotinyalted, Recombinant

CD19 is a single-pass type I transmembrane protein belonging to the immunoglobulin (Ig) superfamily (IgSF).  It contains two Ig-like C2-type domains.  CD19 is an important pan B cell marker and co-stimulatory protein involved in growth regulation of B cells. CD19 is expressed only in B cells and follicular dendritic cells of the hematopoietic system. It is present on most pre-B cells and most non-T-cell acute lymphocytic leukemia cells (ALL) and B-cell type chronic lymphocytic leukemia cells (CLL).  CD19 is a co-receptor for the antigen receptor complex on B cells to decrease the threshold for antigen receptor-dependent stimulation. It forms a complex with CD21, CD81 and CD225 in the membrane of B cells. It associates with GRB2 and SOS when activated and phosphorylated on Tyr-348 / Tyr-378. CD19 is a hallmark differentiation antigen of the B cell lineage and positively regulates antigen B-cell receptor (BCR) signal transduction for B cell selection, maturation, and differentiation.  Defects in CD19 are the cause of immunodeficiency common variable type 3 (CVID3), which is characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of antibody while the numbers of circulating B cells is usually in the normal range, but can be low. The anti-CD19 bispecific antibody recognizes both CD19 and CD3e thus promoting T-cell-mediated anti-tumor activity after engaging with CD19 antigen.

Gene Symbol: CD19; B4; CVID3; Leu-12; CD3E; T3E; TCRE; IMD18; Leu-4

NCBI Gene ID: 930; 916 

Uniprot Entry: P15391; P07766

Construct Details: Expressed as a single-chain Fv (scFv) from anti-CD19 VH and VL region fused with a scFv of anti-CD3e VH and VL region with a His-tag at the C-terminus. Exists as a monomer under non-reducing and reducing condition.

Source: Mammalian cells stably expressing anti-CD19:anti-CD3e bispecific antibody (in a scFv-scFv’ format) and growing in chemical-defined media with no animal component or antibiotics.

M.W.: Calculated molecular mass (kDa): 55.9. Estimated by SDS-PAGE under non-reducing condition(kDa): 55-60. Calculated extinction coefficients (M-1 cm-1, at 280nm):  122660.

Purity: >95% judged by SDS-PAGE under reducing condition (see the gel image above, labeled as DTT "+")

Formulation: Supplied at 0.5 mg/ml in sterile PBS pH7.4 (concentration determined by UV spectrometry and verified by SDS-PAGE and Coomassie blue staining). The purified recombinant protein was labeled with Biotin (3-5 Biotin per molecule) using the standard procedure.

Endotoxin Level: <0.1 EU per 1 μg of purified recombinant protein determined by the LAL method

Biological Activity: Recognizes CD19 on tumor cells and CD3e in the context of TCR complex on T cells.  Potently promotes T cell-mediated anti-tumor activity in vitro and in vivo after engaging with tumor cell surface antigen CD19.

FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.

Restriction: This product is not transferable or re-sellable.  Customer obtain no right to transfer, assign, or sublicense its use rights, or to transfer, resell, package, or otherwise distribute the product, or to use the product for the benefit of any third party or for any commercial purpose.  Customer may only use the product in compliance with applicable local, state and federal laws, regulations and rules.  Customer may not directly or indirectly use the product or allow the transfer, transmission, export or re-export of all or any part of the product in violation of any export control law or regulation of the united states or any other relevant jurisdiction.  Your use of this product constitutes acceptance of the terms of this limited use agreement.  Please refer to our “terms & conditions” for details.  If you are not willing to accept the limitation of this agreement, G&P Biosciences will accept return of the product for a full/partial refund.

The product is shipped at 4°C. Upon receipt, centrifuge the product briefly before opening the vial. It is recommended to store small aliquots at the temperature below –20°C for long-term storage and the product is stable for 3 months. The undiluted protein can be stored at 4°C for no more than 2 weeks.

Use a manual defrost freezer and avoid repeated freeze-thaw cycles.

FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.

1. J. Exp. Med. 168:1205-1210 (1988)

2. J. Immunol. 143:712-717 (1989)

3.  J Immunol. 158:4662-9 (1997).

4. Leuk Lymphoma. 43:613-6 (2002)

5. N. Engl. J. Med. 354:1901-1912 (2006)

Product datasheet (pdf) can be downloaded here: FCL1770B-PDS.pdf

Additional supporting documents, including COA and MSDS are available upon request.

FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.

Restriction: This product is not transferable or re-sellable.  Customer obtain no right to transfer, assign, or sublicense its use rights, or to transfer, resell, package, or otherwise distribute the product, or to use the product for the benefit of any third party or for any commercial purpose.  Customer may only use the product in compliance with applicable local, state and federal laws, regulations and rules.  Customer may not directly or indirectly use the product or allow the transfer, transmission, export or re-export of all or any part of the product in violation of any export control law or regulation of the united states or any other relevant jurisdiction.  Your use of this product constitutes acceptance of the terms of this limited use agreement.  Please refer to our “terms & conditions” for details.  If you are not willing to accept the limitation of this agreement, G&P Biosciences will accept return of the product for a full/partial refund.