Name: Anti-Human CD3 Monoclonal Antibodies
Brand: Syd Labs
SKU: PA007202.m2a
Price: 150.00 USD
Availability: InStock
Rating: 5 (10 reviews)

Catalog No.

Product Name

Size

List Price (US$)

Quantity

PA007202.m2a

In vivo Grade Recombinant Anti-human CD3e Monoclonal Antibody (Clone: OKT3), Mouse IgG2a Kappa

1 mg

150.00

PA007202.m2a

In vivo Grade Recombinant Anti-human CD3e Monoclonal Antibody (Clone: OKT3), Mouse IgG2a Kappa

5 mg

350.00

PA007202.m2a

In vivo Grade Recombinant Anti-human CD3e Monoclonal Antibody (Clone: OKT3), Mouse IgG2a Kappa

25 mg

900.00

Description

PA007202.m2a: In vivo Grade Recombinant Anti-human CD3 Monoclonal Antibody (Clone: OKT3), Mouse IgG2a Kappa

Recombinant mouse IgG2a Monoclonal Antibody.
Clone: OKT3 or OKT-3.
Isotype: Mouse IgG2a kappa.
Source: The anti-human CD3 monoclonal antibody (clone: OKT3) was produced in mammalian cells.
Specificity/Sensitivity: The in vivo grade recombinant mouse monoclonal antibody (clone: OKT3) specifically binds to the human T cell receptor CD3.
Applications: ELISA, flow cytometry, neutralization, functional assays such as bioanalytical PK and ADA assays, and those assays for studying biological pathways affected by the human CD3 protein.
Form of Antibody: 0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Endotoxin: < 1 EU per 1 mg of the protein by the LAL method.
Purity: >95% by SDS-PAGE under reducing conditions and HPLC.

Shipping: The anti-human CD3 monoclonal antibody (clone number: OKT3) 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, -20 to -70°C as supplied.
1 month from date of receipt, 2 to 8°C as supplied.

Background of Anti-Human CD3 antibody (OKT3)

The OKT3 antibody binds to CD3 epsilon of the T cell receptor-CD3 complex found only on mature T cells and medullary thymocytes. An interaction between T cells, OKT3, and monocytes causes T-cell activation (mitogenesis) in vitro. On the other hand, the OKT3 antibody blocks the unique association between the antigen receptor and CD3, and both the generation and function of cytotoxic T cells. After an initial dose of the OKT3 antibody, T cells disappear from the circulation within minutes to hours. During treatment with the OKT3 antibody, T cells bearing the usual array of surface molecules (CD2, CD4, and CD8) reappear in the peripheral blood circulation but these cells are devoid of CD3. After another 48 hours without the OKT3 antibody, the normal array of surface molecules including CD3 appear again on all T cells. The selective removal of CD3 by internalization is thought to be the key mechanism of action of the OKT3 antibody. Comodulation of the antigen receptor with CD3 explains the immunoblocking action of the OKT3 antibody in vivo. The OKT3 antibody is ineffective clinically if the CD3 target molecule is not modulated.

The OKT3 antibody is effective for induction of immunosuppression and for treating initial and steroid-resistant rejections.

References of anti-human CD3e antibody (OKT3):

A Workflow to Achieve Saturation of Fluorophore-Conjugated Monoclonal Antibodies for Robust Comparison of Biomarker Expression
Smith, N., et al. (2025). Cytometry A. doi: 10.1002/cyto.a.24938. PMID: 40298242
The OKT3 antibody (anti-human CD3, mouse IgG2a) was used to develop a workflow for achieving saturation in flow cytometry. Unlabelled OKT3 was titrated with a fluorophore-labeled anti-mouse IgG secondary antibody to determine saturating concentrations, and mixtures of labeled and unlabelled OKT3 maintained fluorescence signals, ensuring robust biomarker expression analysis without loss of binding activity.
Tags: activity of OKT3 antibody; function of OKT3 antibody

Bone marrow-liver-thymus (BLT) immune humanized mice as a model to predict cytokine release syndrome
Yan, H., et al. (2019). Transl Res. doi: 10.1016/j.trsl.2019.04.007. PMID: 31082370
The OKT3 antibody (anti-human CD3, muromonab) was tested in BLT-humanized mice to model cytokine release syndrome (CRS). Dose escalation studies showed significant cytokine increases, T-cell depletion, and activation, with severe outcomes at higher doses. Pretreatment with methylprednisolone reduced cytokine levels, validating OKT3’s role in CRS studies in humanized mouse models.
Tags: OKT3 antibody; OKT3 antibody for animal model

Altered T Lymphocyte Proliferation upon Lipopolysaccharide Challenge Ex Vivo
Poujol, F., et al. (2015). PLoS One. doi: 10.1371/journal.pone.0144375. PMID: 26642057
The OKT3 antibody (anti-human CD3e, 5?50 ng/mL) was used to stimulate PBMCs primed with LPS (0.01?100 ng/mL) in ex vivo assays. LPS priming reduced T-cell proliferation and IFN? secretion in response to OKT3 but not to PHA or anti-CD2/CD3/CD28 beads. IFN? restored monocyte accessory functions and T-cell responses to OKT3, highlighting its role in flow cytometry-based immune studies.
Tags: OKT3 antibody for flow cytometry; OKT3 antibody for mouse tumor model

Comparative analysis of T-cell depletion method for clinical immunotherapy-anti-hepatitis c effects of natural killer cells via interferon-? production
Ohira, M., et al. (2013). Transplant Proc. doi: 10.1016/j.transproceed.2013.01.046. PMID: 23769105
The OKT3 antibody (anti-human CD3e, muromonab) was used to deplete CD3+ T cells in liver mononuclear cell cultures to prevent graft-versus-host disease in NK cell immunotherapy. Compared to alternatives like MACS GMP CD3, antithymocyte globulin, and alemtuzumab, OKT3 showed equivalent T-cell depletion and NK cell activation, promoting anti-HCV effects via IFN? production.
Tags: OKT3 antibody mouse dose range; OKT3 mAb

Ex vivo expansion of human CD8+ T cells using autologous CD4+ T cell help
Butler, M. O., et al. (2012). PLoS One. doi: 10.1371/journal.pone.0030229. PMID: 22279573
The OKT3 antibody (anti-human CD3) was expressed as a membranous form in a novel artificial antigen-presenting cell (aAPC/mOKT3) to expand CD8+ T cells without allogeneic feeders. This system avoided Foxp3+ Treg expansion, promoted Th1 cytokine secretion (IFN?, IL-2), and enhanced CD8+ T cell proliferation with autologous CD4+ T cell help, partially mediated by IL-2/IL-21.
Tags: OKT3 mAb for flow cytometry; OKT3 mAb for mouse tumor model

For more references about anti-human CD3e antibody (OKT3), please contact our scientific support team with message@sydlabs.com.