Human CD3-epsilon/delta Heterodimer, His-Avi Tag

Human cluster of differentiation 3 (CD3) epsilon/delta (CD3δε, CD3-epsilon/delta) heterodimer contains CD3-epsilon and CD3-delta within the CD3 complex. CD3 complex is a crucial part of the T cell receptor (TCR). CD3-epsilon and CD3-delta are Type I transmembrane proteins and members of the immunoglobulin superfamily. CD3-epsilon and CD3-delta each contain an extracellular domain composed of an immunoglobulin domain followed by a short a membrane-proximal connecting peptide, a transmembrane domain, and an intracellular domain. CD3-epsilon/delta together with CD3-epsilon/gamma heterodimer, T-cell receptor-alpha/beta (TCR), and CD3-zeta homodimer make up the TCR complex. CD3 can act as a marker antigen due to its presence in almost all T-cell lymphomas and leukemias and can be used to distinguish them from other cancers. Because CD3 is required for T-cell activation, it has become an important target for developing cancer therapeutics, as well as immunosuppressant therapies for type 1 diabetes and other autoimmune diseases. In the T cell receptor, CD3-epsilon/delta is responsible for transmitting activation signals when the TCR recognizes an antigen and is involved in activating both the cytotoxic T cell and T helper cells. Therefore, a recombinant CD3-epsilon/delta protein heterodimer mimicking the CD3-epsilon/delta heterodimer native conformation can be critical for target for drug discovery and immunotherapy research.