Background：T cell receptor （TCR） is a heterodimer consisting of an a and a b chain （TCR a/b） or a gamma and a delta chain （TCR gamma/delta）. TCR-b is a member of the immunoglobulin superfamily and a component of the CD3/TCR complex （along with TCR-a）. It is expressed on a/b TCR-bearing T cells and thymocytes. The CD3/TCR complex plays a key role in antigen recognition, signal transduction, and T cell activation.
