Anti-mCD3

Anti-mCD3-mIgG2a InvivoFit™ is an anti-mCD3 monoclonal antibody featuring the variable region of the previously described 145-2C11 clone [1] and a murinized IgG2a constant region.

CD3 is a multimeric protein complex consisting of four polypeptides (CD3ε, CD3γ, CD3δ, and CD3ζ) that assemble as three dimers (εγ, εδ, and ζζ) [2]. The CD3 complex is a marker of T cells [2]. Upon antigen recognition, the TCR/CD3 complex on T cells triggers downstream intracellular signaling and participates in T cell activation  [3]. 

The anti-mCD3ε 145-2C11 mAb is commonly used for cytometry detection and in vivo depletion of the T cell population [1]. Using recombinant technology, the original 145-2C11 Armenian Hamster IgG1 constant region has been replaced with a murine IgG2a format which mediates potent cytotoxic functions [4]. This murinization also allows reduced immunogenicity of the administered mAb and risks for fatal hypersensitivity reactions [5-7].

Key features:

• Derives from the 145-2C11 clone, Armenian Hamster IgG1
• Features the mIgG2a isotype (constant region)
• Guaranteed sterile, endotoxin level < 1 EU/mg
• Suitable for parental delivery in mice (azide-free)
• Low aggregation < 5%
• Produced in animal-free facilities and defined media

Anti-mCD3-mIgG2a InvivoFit™ is produced in Chinese hamster ovary (CHO) cells, purified by affinity chromatography with protein A, and provided in an InvivoFit™ grade, a high-quality standard specifically adapted to in vivo studies. The specific binding of this mAb to mCD3 has been confirmed by FACS and ELISA (see Figures).

References:

1. Leo O., et al., 1986. Identification of a monoclonal antibody specific for a murine T3 polypeptide. PNAS. 84(5):1374-1378.
2. Chetty R. & Gatter K., 1994. CD3: structure, function, and role of immunostaining in clinical practice. J. Pathol. 173(4):303-307.
3. Smith-Garvin J.E. et al., 2009. T Cell Activation. Ann. Rev. Immunol. 27:591-619.
4. Nimmerjahn F. & Ravetch J.V., 2005. Divergent immunoglobulin g subclass activity through selective Fc receptor binding. Science. 310(5753):1510-2.
5. Mall C. et al., 2016. Repeated PD-1/PD-L1 monoclonal antibody administration induces fatal xenogenic hypersensitivity reactions in a murine model of breast cancer. Onco Immunol. 5(2):e1075114.
6. Murphy, J.T. et al., 2014. Anaphylaxis caused by repetitive doses of a GITR agonist monoclonal antibody in mice. Blood. 123(14):2172-2180.
7. Belmar N.A. et al., 2017. Murinization and H chain isotype matching of Anti-GITR antibody DTA-1 reduces immunogenicity-mediated anaphylaxis in C57BL/6 mice. J Immunol. 198:4502-4512.