mouse monoclonal IgG1; CD3-ε Antibody (UCH-T1) is an IgG1 κ mouse monoclonal CD3-epsilon antibody (also designated CD3 antigen epsilon polypeptide antibody, CD3E antibody, or CD3 epsilon antibody) that detects the CD3-epsilon protein of human origin by WB, IP, IF, IHC(P) and FCM. CD3-ε Antibody (UCH-T1) is available as both the non-conjugated anti-CD3-epsilon antibody form, as well as multiple conjugated forms of anti-CD3-epsilon antibody, including agarose, HRP, PE, FITC and multiple Alexa Fluor® conjugates. The T cell antigen receptor (TCR) recognizes foreign antigens and translates such recognition events into intracellular signals that elicit a change in the cell from a dormant to an activated state. Much of this signaling process can be attributed to a multisubunit complex of proteins that associates directly with the TCR. This complex has been designated CD3 (cluster of differentiation 3). It is composed of five invariant polypeptide chains that associate to form three dimers: a heterodimer of gamma and epsilon chains (CD3-γ and CD3-ε), a heterodimer of delta and epsilon chains (CD3-δ and CD3-ε) and a homodimer of two zeta chains (CD3-ζ) or a heterodimer of zeta and eta chains (CD3-ζ and CD3-η). CD3-ζ and CD3-η are encoded by the same gene, but differ in their carboxyl-terminal ends due to an alternative splicing event. CD3-γ, CD3-ε and CD3-δ each contain a single copy of a conserved immunoreceptor tyrosine-based activation motif (ITAM). In contrast, CD3-ζ contains three consecutive copies of the same motif. Phosphorylated ITAMs act as docking sites for protein kinases such as ZAP-70 and Syk and are also capable of regulating their kinase activity. The crystal structure of the ZAP-70 SH2 domains bound to CD3-ζ ITAMs has been solved.