B-lymphocyte antigen CD19 (CD19), also known as B4, is an IgSF surface glycoprotein of 95 kDa encoded by CD19 gene in humans. It mainly assembles with the antigen receptor of B-lymphocytes in order to decrease the threshold for antigen receptor-dependent stimulation. It is the most common marker of B cell.
CD19 is type I one-pass transmembrane protein, with a single transmembrane domain, a cytoplasmic C-terminus, and extracellular N-terminus. The extracellular domain contains two C2-type Ig-like domains separated by small helical non-Ig domain with possible disulfide links, as well as N-linked carbohydrate addition sites. The highly conserved cytoplasmic domain consists of 242 amino acids with nine tyrosine residues near the C-terminus. No significant homology exists between CD19 and other known proteins.
CD19 is critically involved in establishing intrinsic B cell signaling thresholds through modulating both B cell receptor (BCR)-dependent and independent signaling. CD19 is thus critical for the body to mount an optimal immune response. CD19 works in complex with the BCR and other surface molecules to allow both direct and indirect recruitment and binding of various down-stream protein kinases.
Multiple studies have come to suggest that the biologic functions of CD19 are dependent on three cytoplasmic tyrosine residues – Y391, Y482 and Y513. Experiments have shown that substitution of phenylalanine for tyrosine at two of the positions, Y482 and Y513, leads to inhibited phosphorylation of the other seven tyrosines.
CD19 is one of the important membrane antigens involved in the activation and proliferation of B cells. It is a common surface marker of all B cells. It doesn’t disappear after activation of B cells. In the bulk of the body, the extracellular portion of CD19 binds to other membrane antigens for signal transduction.
CD19-positive cells are elevated in malignant tumors of the B-lymphocyte system, such as CD19 in 95% of acute pre-B lymphocyte leukemia cells and 94% of acute mature B-lymphocytic leukemia cells. Moreover, CD19-positive cells are also found in chronic lymphocytic leukemia and Burkitt lymphoma. CD19-positive cell reduction is seen in humoral immunodeficiency diseases.
Therefore, CD19 detection can make a clear cause diagnosis of the above diseases, and provide a basis for differential diagnosis.
Further Reading: CD19-The Most Popular Target with CAR T-Cell Therapy
1. BLINCYTO TM , also called blinatumomab, is a drug that targets B-lymphocyte antigen CD19. It is developed by Amgen Inc., and the initial approval was in December, 2014. This drug is mainly applied in the treatment of acute lymphoblastic leukaemia (ALL).
2. KYMRIAH, also called tisagenlecleucel, is a drug that targets B-lymphocyte antigen CD19. It is developed by Novartis Pharmaceuticals Corporation., and the initial approval was in August, 2017. This drug is mainly applied in the treatment of acute lymphoblastic leukaemia (ALL).
3. YESCARTA, also called axicabtagene ciloleuce, also is a drug that targets B-lymphocyte antigen CD19. It is developed by Kite Pharma, Incorporated, and the initial approval was in October, 2017. Compared with the two drugs before, this drug is involved in three diseases treatment, including B-cell lymphoma, diffuse large B cell lymphoma and follicular lymphoma.
● CD19 Recombinant Monoclonal Antibody CSB-RA004888MA1HU
Validated Data
Positive WB detected in: Raji whole cell lysate,JK whole cell lysate
All lanes: CD19 antibody at 1:1000
Secondary
Goat polyclonal to mouse IgG at 1/50000 dilution
Predicted band size: 62 kDa
Observed band size: 62 kDa
The following CD19 reagents supplied by CUSABIO are manufactured under a strict quality control system. Multiple applications have been validated and solid technical support is offered.
CD19 Antibodies for Homo sapiens (Human)
Code | Product Name | Species Reactivity | Application |
---|---|---|---|
CSB-PA058389 | Phospho-CD19 (Tyr531) Antibody |
Human,Mouse | ELISA,WB |
CSB-PA253616 | CD19 (Ab-531) Antibody |
Human,Mouse | ELISA,WB |
CSB-PA001431 | CD19 Antibody |
Human,Mouse,Monkey | WB, ELISA |
CSB-PA006159 | CD19 Antibody |
Human | WB, ELISA |
CSB-PA070286 | Phospho-CD19 (Y531) Antibody |
Human,Mouse,Monkey | WB, ELISA |
CSB-RA004888A0HU | CD19 Recombinant Monoclonal Antibody |
Human | ELISA |
CSB-MA004888A1m | CD19 Monoclonal Antibody |
Human | ELISA, WB, IHC, FC |
CSB-MA004888A0m | CD19 Monoclonal Antibody |
Human | ELISA, WB, IHC, IF, FC |
CSB-RA780821A0HU | CD19 Recombinant Monoclonal Antibody |
Human | ELISA, WB, IHC, IP |
CSB-RA004888MA1HU | CD19 Recombinant Monoclonal Antibody |
Human | ELISA, WB |
CD19 Proteins for Homo sapiens (Human)
Code | Product Name | Source |
---|---|---|
CSB-YP004888HU CSB-BP004888HU CSB-EP004888HU-B |
Recombinant Human B-lymphocyte antigen CD19 (CD19), partial |
Yeast Baculovirus In Vivo Biotinylation in E.coli |
CSB-CF004888HU | Recombinant Human B-lymphocyte antigen CD19 (CD19), partial |
in vitro E.coli expression system |
CSB-CF004888HUc7 | Recombinant Human B-lymphocyte antigen CD19 (CD19), partial |
in vitro E.coli expression system |
CSB-AP005061HU | Recombinant Human B-lymphocyte antigen CD19 (CD19), partial (Active) |
Mammalian cell |
CSB-MP004888HU | Recombinant Human B-lymphocyte antigen CD19 (CD19), partial |
Mammalian cell |
CD19 Proteins for Cavia porcellus (Guinea pig)
Code | Product Name | Source |
---|---|---|
CSB-YP004888GU CSB-EP004888GU CSB-BP004888GU CSB-MP004888GU CSB-EP004888GU-B |
Recombinant Guinea pig B-lymphocyte antigen CD19 (CD19), partial |
Yeast E.coli Baculovirus Mammalian cell In Vivo Biotinylation in E.coli |
CD19 Proteins for Callithrix jacchus (White-tufted-ear marmoset)
Code | Product Name | Source |
---|---|---|
CSB-YP660773CYL CSB-EP660773CYL CSB-BP660773CYL CSB-MP660773CYL CSB-EP660773CYL-B |
Recombinant Callithrix jacchus B-lymphocyte antigen CD19 (CD19), partial |
Yeast E.coli Baculovirus Mammalian cell In Vivo Biotinylation in E.coli |
CD19 Proteins for Mus musculus (Mouse)
Code | Product Name | Source |
---|---|---|
CSB-CF004888MO | Recombinant Mouse B-lymphocyte antigen CD19 (Cd19) |
in vitro E.coli expression system |
CSB-YP004888MO1 CSB-EP004888MO1 CSB-BP004888MO1 CSB-MP004888MO1 CSB-EP004888MO1-B |
Recombinant Mouse B-lymphocyte antigen CD19 (Cd19), partial |
Yeast E.coli Baculovirus Mammalian cell In Vivo Biotinylation in E.coli |
CD19 Proteins for Recombinant Homo sapiens (Human)
Code | Product Name | Source |
---|---|---|
CSB-EP004888HU | Recombinant Human B-lymphocyte antigen CD19 (CD19), partial |
E.coli |