Anti-human CD3 Monoclonal Antibodies for Flow Cytometry

PA007421.m1: Non-conjugated Recombinant Anti-human CD3E Monoclonal Antibody (Clone: SP34-2), Mouse IgG1 Lambda

Recombinant  Mouse IgG1 Monoclonal Antibody. 
Clone: SP34-2.
Isotype:  Mouse IgG1 lambda.
Source: The anti-human CD3E monoclonal antibody (clone: SP34-2) was produced in mammalian cells.
Conjugation: Non-conjugated.
Specificity/Sensitivity: The recombinant SP34-2 antibody specifically binds to the human, cynomolgus and rhesus T cell receptor CD3 epsilon subunit in denatured form and in native form.
Applications: Flow cytometry (FC), and Immunohistochemistry - Frozen (IHC-F). 
Form of Antibody: 0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Purity: >95% by SDS-PAGE under reducing conditions.

PA007421.h1Fs: Non-conjugated Recombinant Anti-human CD3E Monoclonal Antibody (Clone: SP34-2), Human IgG1 Fc Silent Kappa

Recombinant  Human IgG1 Monoclonal Antibody with Fc silent mutation. 
Clone: SP34-2.
Isotype: Human IgG1 kappa.
Source: The anti-human CD3 monoclonal antibody (clone: SP34-2) was produced in mammalian cells.
Conjugation: Non-conjugated.
Specificity/Sensitivity: The recombinant SP34-2 antibody specifically binds to the human, cynomolgus and rhesus T cell receptor CD3 epsilon subunit in denatured form and in native form.
Applications: Flow cytometry (FC), and Immunohistochemistry - Frozen (IHC-F). 
Form of Antibody: 0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Purity: >95% by SDS-PAGE under reducing conditions.

PA007751.m1-b: Biotinylated Recombinant Anti-human CD3E Monoclonal Antibody (Clone: SP34-2), Mouse IgG1 Lambda

Recombinant  Mouse IgG1 Monoclonal Antibody  with site-directed  biotinylation through the Avi tag at the C-terminus of the antibody heavy chain.
Clone: SP34-2.
Isotype:  Mouse IgG1 lambda.
Source: The site-directed biotinylated anti-human CD3E monoclonal antibody (clone: SP34-2) was produced in mammalian cells.
Conjugation: Biotin-conjugated.
Specificity/Sensitivity: The site-directed biotinylated recombinant SP34-2 antibody specifically binds to the human, cynomolgus and rhesus T cell receptor CD3 epsilon subunit in denatured form and in native form.
Applications: Flow cytometry (FC) with various dye conjugation through streptavidin; conjugation to streptavidin agarose beads or streptavidin magnetic beads.
Form of Antibody: 0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Purity: >95% by SDS-PAGE under reducing conditions.

Shipping: The SP34-2 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, -20 to -70°C as supplied.
1 month from date of receipt, 2 to 8°C as supplied.

Background:

The 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, SP34-2, and monocytes causes T-cell activation (mitogenesis) in vitro. On the other hand, the 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  antibody, T cells disappear from the circulation within minutes to hours. During treatment with the 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 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  antibody. Comodulation of the antigen receptor with CD3 explains the immunoblocking action of the antibody in vivo. The  antibody is ineffective clinically if the CD3 target molecule is not modulated.

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

References of anti-human CD3 antibody (SP34-2):

Generalizable design parameters for soluble T cell receptor-based T cell engagers
Froning, K. J., et al. (2022). J Immunother Cancer. 2022 Mar;10(3):e004281. doi: 10.1136/jitc-2021-004281. PMID: 35260435
The SP34-2 antibody (anti-human CD3, phycoerythrin-conjugated) was used in a flow cytometry competition assay to assess rTCR/anti-CD3 bispecific fusion proteins (BFPs). SP34-2 staining at 2.25 µg/mL helped evaluate cell surface MHC-peptide binding and redirected lysis in cancer testis antigen assays, confirming BFP functionality in tumor cell killing.
Tags: SP34-2 antibody; anti-human CD3 antibody

Human Cytomegalovirus Infection Promotes Expansion of a Functionally Superior Cytoplasmic CD3+ NK Cell Subset with a Bcl11b-Regulated T Cell Signature
Wu, Z., et al. (2021). J Immunol. 2021 Nov 15;207(10):2534-2544. doi: 10.4049/jimmunol.2001319. PMID: 34625521
The SP34-2 antibody (anti-human CD3) was used in flow cytometry to detect cytoplasmic CD3ε in CD56dim NK cells, showing positive staining in all cells compared to only 20% with other clones like SK7. SP34-2, alongside UCHT1 and SK7, confirmed the presence of CD3ε in NK cells from healthy donors.
Tags: anti-human CD3 antibody for flow cytometry; activity of SP34-2 antibody

Efficient tumor killing and minimal cytokine release with novel T-cell agonist bispecific antibodies
Trinklein, N. D., et al. (2019). MAbs. 2019 Jan;11(1):53-70. doi: 10.1080/19420862.2019.1574521. PMID: 30698484
The SP34-2 antibody (anti-human CD3, APC-conjugated) was used in flow cytometry to stain activated PBMCs after incubation with anti-CD3 FlicAbs or control mAbs like OKT3. SP34-2 staining, combined with 7-AAD viability dye, confirmed T-cell activation and supported cytotoxicity assays showing dose-dependent tumor cell killing by bispecific antibodies.
Tags: function of SP34-2 antibody; SP34-2 mAb for flow cytometry

OMIP-005: Quality and Phenotype of Antigen-Responsive Rhesus Macaque T Cells
Foulds, K. E., Donaldson, M., Roederer, M. (2012). Cytometry A. 2012 May;81(5):360-1. doi: 10.1002/cyto.a.22008. PMID: 22438313
The SP34-2 antibody (anti-human CD3) was included in the intracellular staining portion of an eight-color flow cytometry panel to measure cytokine production (IFN-γ, IL-2, TNF) in rhesus macaque T cells. SP34-2 ensured accurate detection of CD3+ cells, including activated T cells with internalized CD3, in preclinical vaccine studies.
Tags: SP34-2 antibody for animal model; SP34-2 monoclonal antibody

Evaluation of a 12-Color Flow Cytometry Panel to Study Lymphocyte, Monocyte, and Dendritic Cell Subsets in Humans
Autissier, P., Soulas, C., Burdo, T. H., Williams, K. C. (2010). Cytometry A. 2010 May;77(5):410-9. doi: 10.1002/cyto.a.20859. PMID: 20099249
The SP34-2 antibody (anti-human CD3, Alexa Fluor 700 or Cy7-PE) was used in a 12-color flow cytometry panel on a FACSAria cytometer to identify T-cell subsets in human whole blood. SP34-2 staining, alongside other markers, enabled precise characterization of lymphocyte, monocyte, and dendritic cell populations.
Tags: SP34-2 antibody for mouse tumor model; anti-human CD3 SP34-2 mAb for flow cytometry

For more references about anti-human CD3 antibody (SP34-2), please contact our scientific support team with message@sydlabs.com.

Syd Labs provides the following in vivo grade recombinant anti-human CD3 monoclonal antibodies:
Muromonab biosimilar, research grade, anti-human CD3 monoclonal antibody (Clone: OKT3)
Teplizumab biosimilar, research grade, anti-human CD3 monoclonal antibody (Clone: OKT3)
Foralumab biosimilar, research grade, anti-human CD3 monoclonal antibody (Clone: OKT3)
Recombinant Anti-human CD3 monoclonal antibody (Clone: OKT3)
Recombinant Anti-human CD3 monoclonal antibody (Clone: SP34-2)
Recombinant Anti-human CD3 monoclonal antibody (Clone: UCHT1)
Recombinant Anti-human CD3 monoclonal antibody (Clone: 12F6)

Syd Labs provides the following in vivo grade recombinant anti-human CD3 bispecific antibodies:
Recombinant Anti-human CD3 / CD3 Bispecific Antibody (Clone: OKT3 / UCHT1)
Recombinant Anti-human CD3 / CD3 Bispecific Antibody (Clone: OKT3 / SP34-2)
Recombinant Anti-human CD3 / CD3 Bispecific Antibody (Clone: SP34-2 / OKT3)

Syd Labs provides the following in vivo grade recombinant anti-mouse CD3 monoclonal antibodies:
Recombinant Anti-mouse CD3e monoclonal antibody (Clone: 145-2C11)
Recombinant Anti-mouse CD3e monoclonal antibody (Clone: 500A2)
Recombinant Anti-mouse CD3 monoclonal antibody (Clone: 17A2)
Recombinant Anti-mouse CD3e monoclonal antibody (Clone: KT3)

Syd Labs provides the following recombinant anti-human CD3 monoclonal antibodies for flow cytometry:
Recombinant Anti-human CD3 monoclonal antibody (Clone: OKT3) for flow cytometry
Recombinant Anti-human CD3 monoclonal antibody (Clone: UCHT1) for flow cytometry
Recombinant Anti-human CD3 monoclonal antibody (Clone: 12F6) for flow cytometry
Recombinant Anti-human CD3 monoclonal antibody (Clone: SP34-2) for flow cytometry

Syd Labs provides the following recombinant anti-mouse CD3 monoclonal antibodies for flow cytometry:
Recombinant Anti-mouse CD3 monoclonal antibody (Clone: 17A2) for flow cytometry
Recombinant Anti-mouse CD3e monoclonal antibody (Clone: 145-2C11) for flow cytometry
Recombinant Anti-mouse CD3e monoclonal antibody (Clone: 500A2) for flow cytometry
Recombinant Anti-mouse CD3e monoclonal antibody (Clone: KT3) for flow cytometry