Anti-human CD19 Monoclonal Antibodies for Flow Cytometry

PA007511.m1: Non-conjugated Recombinant Anti-human CD19 Monoclonal Antibody (Clone: 4G7), Mouse IgG1 Kappa

Recombinant Mouse IgG1 Monoclonal Antibody. 
Clone: 4G7.
Isotype:  Mouse IgG1 kappa.
Source: The recombinant anti-human CD19 monoclonal antibody (clone: 4G7) was produced in mammalian cells.
Conjugation: Non-conjugated.
Specificity/Sensitivity: The recombinant 4G7 antibody specifically binds to the human CD19 protein.
Applications: Flow cytometry (FC), and Immunohistochemistry - Frozen (IHC-F). 
Form of Antibody: 0.2 uM filtered solution, pH 7.4, containing 0.09% sodium azide.
Purity: >95% by SDS-PAGE under reducing conditions.

PA007511.h1Fs: Non-conjugated Recombinant Anti-human CD19 Monoclonal Antibody (Clone: 4G7), Human IgG1 Fc Silent Kappa

Recombinant human IgG1 monoclonal antibody with Fc silent mutation.
Clone: 4G7.
Isotype: Human IgG1 kappa.
Source: The recombinant anti-human CD19 monoclonal antibody (clone: 4G7) was produced in mammalian cells.
Conjugation: Non-conjugated.
Specificity/Sensitivity: The recombinant 4G7 antibody specifically binds to the human CD19 protein.
Applications: Flow cytometry (FC), and Immunohistochemistry - Frozen (IHC-F). 
Form of Antibody: 0.2 uM filtered solution, pH 7.4, containing 0.09% sodium azide.
Purity: >95% by SDS-PAGE under reducing conditions.

Shipping: The 4G7 antibody is shipped with ice pack. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles. 
12 months from date of receipt, 2 to 8°C as supplied. Do not freeze it.

Syd Labs provides the following recombinant anti-human CD19 monoclonal antibodies for flow cytometry:

Non-conjugated Recombinant Anti-human CD19 Monoclonal Antibody (Clone: 4G7), Mouse IgG1 Kappa
Non-conjugated Recombinant Anti-human CD19 Monoclonal Antibody (Clone: 4G7), Human IgG1 Fc Silent Kappa

Background:

The 4G7 antibody binds to the human CD19 protein, a transmembrane protein expressed in all B lineage cells including human plasma cells. CD19 plays two major roles in human B cells: it acts as an adaptor protein to recruit cytoplasmic signaling proteins to the membrane, and works within the CD19/CD21 complex to decrease the threshold for B cell receptor signaling pathways. CD19 is a biomarker for B lymphocyte development, lymphoma diagnosis and can be utilized as a target for leukemia immunotherapies.

References of anti-human CD19 antibody (4G7):

Sequencing of Anti-CD19 Therapies in the Management of Diffuse Large B-Cell Lymphoma.
Lownik, J., et al. (2024). Clin Cancer Res. 2024 Jul 15;30(14):2895-2904. doi: 10.1158/1078-0432.CCR-24-0363. PMID: 38661647
Epitope mapping of the CD19 extracellular domain revealed that the antigen-recognition domains of CAR-T cells (based on FMC63 antibody) and tafasitamab (based on 4G7 antibody) have partially overlapping, conformationally sensitive epitopes dependent on spatially adjacent loops coded by exons 3 and 4. Splice variations in exon 2 could lead to epitope loss for both therapies. The study emphasizes the need for prospective studies to correlate pretreatment and posttreatment CD19 expression with clinical responses to optimize sequencing of CD19-directed immunotherapies for diffuse large B-cell lymphoma (DLBCL).
Tags: 4G7 antibody; anti-human CD19 antibody for flow cytometry

IgG-Based Bispecific Anti-CD95 Antibodies for the Treatment of B Cell-Derived Malignancies and Autoimmune Diseases.
Hörner, S., et al. (2022). Cancers (Basel). 2022 Aug 16;14(16):3941. doi: 10.3390/cancers14163941. PMID: 36010934
The study utilized codon-optimized variable domains of humanized Apo-1, 2H7, 4G7 (anti-human CD19), and MOPC-21 antibodies for transfection into CHO cells. Bispecific antibodies combined the CD95 agonist Apo-1 with either anti-CD20 (clone 2H7) or anti-CD19 (clone 4G7) in F(ab)2 and single-chain formats. The CD19 binding affinity showed an EC50 of approximately 7.5 nM, despite 4G7’s higher affinity compared to 2H7. Flow cytometry revealed CD20 expression was 3–10-fold higher than CD19, with Raji cells expressing over 20,000 CD19 and 190,000 CD20 molecules per cell.
Tags: 4G7 antibody for flow cytometry; 4G7 monoclonal antibody

Reduction of Minimal Residual Disease in Pediatric B-lineage Acute Lymphoblastic Leukemia by an Fc-optimized CD19 Antibody.
Seidel, U. J., et al. (2016). Mol Ther. 2016 Sep 6;24(9):1634-43. doi: 10.1016/j.ymthe.2016.06.008. PMID: 27380762
The Fc-optimized CD19 antibody 4G7SDIE, a humanized version of the murine 4G7 antibody (anti-human CD19) with S239D and I332E modifications, was tested in B-lineage ALL blasts from 18 patients and 5 4G7SDIE-treated patients. The antibody was detected via indirect immunofluorescence staining and flow cytometry. 4G7SDIE enhanced antibody-dependent cellular cytotoxicity (ADCC) against leukemic blasts, showing promise for minimal residual disease (MRD) treatment due to favorable target-to-effector cell ratios.
Tags: anti-human CD19 4G7 mAb for flow cytometry; anti-human CD19 4G7 of low endotoxin

Heterodimeric bispecific antibody-derivatives against CD19 and CD16 induce effective antibody-dependent cellular cytotoxicity against B-lymphoid tumor cells.
Kellner, C., et al. (2011). Cancer Lett. 2011 Jul 28;306(1):88-95. doi: 10.1016/j.canlet.2011.02.023. PMID: 21339041
The study utilized the 4G7 hybridoma (anti-human CD19; IgG1) and 3G8 (CD16; IgG1) to create Fab–scFv fusion proteins combining CD19-directed Fab fragments with CD19 and CD16 scFvs. CD19, a 95 kDa transmembrane glycoprotein, is a promising target for B-cell malignancy treatments due to its favorable properties. The bispecific antibodies demonstrated effective antibody-dependent cellular cytotoxicity (ADCC) against B-lymphoid tumor cells, highlighting CD19’s potential in immunotherapy.
Tags: anti-CD19 (4G7) monoclonal antibody; human CD19 antibody (clone 4G7)

Potent In vitro and In vivo Activity of an Fc-Engineered Anti-CD19 Monoclonal Antibody against Lymphoma and Leukemia.
Horton, H. M., et al. (2008). Cancer Res. 2008 Oct 1;68(19):8049-57. doi: 10.1158/0008-5472.CAN-08-1265. PMID: 18829563
The study developed XmAb5574, a humanized and affinity-matured version of the mouse anti-CD19 antibody 4G7 with S239D/I332E Fc modifications. XmAb5574 and other anti-CD19 antibodies showed approximately 2-fold higher binding affinity than 4G7. In vitro, target cells opsonized with antibodies were mixed with NK cells, and LDH release was measured. In vivo, fluorescence-activated cell sorting confirmed CD19 expression and tumor cell percentages, demonstrating potent activity against lymphoma and leukemia.
Tags: anti-human CD19 4G7 in animal model; anti-human CD19 4G7 mAb for flow cytometry

For more references about anti-human CD19 antibody (4G7), please contact our scientific support team with message@sydlabs.com.

Syd Labs provides the following recombinant anti-mouse CD19 monoclonal antibodies for flow cytometry:
Recombinant Anti-mouse CD19 monoclonal antibody (Clone: 1D3) for flow cytometry

Syd Labs provides the following recombinant anti-human CD19 monoclonal antibodies for flow cytometry:
Recombinant Anti-human CD19 monoclonal antibody (Clone: SJ25C1) for flow cytometry
Recombinant Anti-human CD19 monoclonal antibody (Clone: FMC63) for flow cytometry
Recombinant Anti-human CD19 monoclonal antibody (Clone: B43) for flow cytometry

Syd Labs provides the following in vivo grade recombinant anti-mouse CD19 monoclonal antibodies:
Recombinant Anti-mouse CD19 monoclonal antibody (Clone: 1D3)

Syd Labs provides the following in vivo grade recombinant anti-human CD19 monoclonal antibodies:
Recombinant Anti-human CD19 monoclonal antibody (Clone: SJ25C1)
Recombinant Anti-human CD19 monoclonal antibody (Clone: B43)
Recombinant Anti-human CD19 monoclonal antibody (Clone: FMC63)