Sandwich ELISA: CD19 Antibody Pair [H00000930-AP41] - Quality Control Testing: Standard curve using recombinant protein ( H00000930-Q01 ) as an analyte. Sandwich ELISA detection sensitivity ranging from 0.03 ng/ml to ...read more
Quality control test: Standard curve using recombinant protein (H00000930-Q01) as an analyte. This antibody pair set comes with matched antibody pair to detect and quantify protein level of human CD19.
Standard Curve Range
0.3 ng/ml to 100 ng/ml
Assay Type
Sandwich ELISA
Gene
CD19
Applications/Dilutions
Dilutions
Sandwich ELISA 0.3 ng/ml - 100 ng/ml
Application Notes
Reagents are sufficient for at least 3-5 x 96 well plates using recommended protocols.
This product is produced by and distributed for Abnova, a company based in Taiwan.
Alternate Names for CD19 Antibody Pair
B4
B-lymphocyte antigen CD19
B-lymphocyte surface antigen B4
CD19 antigen
CD19 molecule
CD19
CVID3
Differentiation antigen CD19
Leu-12
MGC12802
T-cell surface antigen Leu-12
Background
CD19 (Cluster of Differentiation 19), also known as B-lymphocyte surface antigen B4, is a type 1 transmembrane glycoprotein belonging to immunoglobulin (Ig) subfamily that serves as a biomarker for normal and neoplastic B cells (1,2). CD19 is a co-receptor for the B cell receptor (BCR) signaling complex and has a critical role in regulating B cell signaling and immune response (1,2). The CD19 protein contains an extracellular N-terminus containing two C2 Ig-like domains separated by a helical non-Ig domain, a single pass transmembrane domain, and a highly conserved cytoplasmic C-terminal domain (1,2). The human CD19 protein, encoded by the CD19 gene located on chromosome 16p11.2, is 556 amino acids (aa) in length with a calculated theoretical molecular weight (MW) of 61 kDa and an observed molecular weight of 95 kDa (1-3). CD19 associates with other molecules - CD21, CD81, and CD225 - to form the BCR co-complex, also called the CD19 complex, through CD21 binding to the complement C3d complex (1-3). Complement C3d bridges the BCR with the CD19 complex into lipid rafts of the plasma membrane (1-3). CD19 is capable of modulating B cell development through both BCR-dependent and -independent signaling (1-3). Upon BCR activation, the tyrosine residues of CD19's cytoplasmic tail recruits multiple kinases including Lyn, Vav, and PI3K, amplifying BCR-mediated immune signaling and B cell activation (1-3).
Considering the role of CD19 in BCR signaling and its expression in development from pre-B cells through plasma cells, it is understandable that CD19 dysfunction and abnormal expression is associated with numerous B cell malignancies and autoimmune disorders (1-5). CD19 expression is typically observed at relatively normal levels in B cell acute lymphoblastic leukemia (B-ALL) and chronic lymphoblastic leukemia (CLL) but is often reduced other types of lymphoma including diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL) (1,2). On the other hand, CD19 expression is typically increased in autoimmune disorders such as systemic sclerosis (SSc) and multiple sclerosis (MS) as modeled by experimental autoimmune encephalomyelitis (EAE) (2). CD19 has become a therapeutic molecular target for the treatment of B cell lymphomas and autoimmune disorders using monoclonal antibodies (mAbs), bi-specific T cell engaging (BiTE) antibodies, and CD19-specific chimeric antigen receptor (CAR) T cells (1,2,4-6). Although anti-CD19 CAR T cell therapy has become the standard for the treatment of B cell malignancies, patients may experience relapse due to resistance mechanisms (6). Strategies to improve efficacy and limit relapse include combination of CAR T cell therapy with immune checkpoint inhibitors like anti-PD-1 (4,6).
References
1. Wang K, Wei G, Liu D. CD19: a biomarker for B cell development, lymphoma diagnosis and therapy. Exp Hematol Oncol. 2012;1(1):36. https://doi.org/10.1186/2162-3619-1-36
2. Li X, Ding Y, Zi M, et al. CD19, from bench to bedside. Immunol Lett. 2017;183:86-95. https://doi.org/10.1016/j.imlet.2017.01.010
3. Wentink MWJ, van Zelm MC, van Dongen JJM, Warnatz K, van der Burg M. Deficiencies in the CD19 complex. Clin Immunol. 2018;195:82-87. https://doi.org/10.1016/j.clim.2018.07.017
4. Frigault MJ, Maus MV. State of the art in CAR T cell therapy for CD19+ B cell malignancies. J Clin Invest. 2020;130(4):1586-1594. https://doi.org/10.1172/JCI129208
5. Penack O, Koenecke C. Complications after CD19+ CAR T-Cell Therapy. Cancers (Basel). 2020;12(11):3445. https://doi.org/10.3390/cancers12113445
6. Bouziana S, Bouzianas D. Anti-CD19 CAR-T cells: Digging in the dark side of the golden therapy. Crit Rev Oncol Hematol. 2021;157:103096. https://doi.org/10.1016/j.critrevonc.2020.103096
Limitations
This product is for research use only and is not approved for use in humans or in clinical diagnosis. Antibody Pairs are guaranteed for 6 months from date of receipt.
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