TCRb is used as a phenotypic marker for TCRb expressing T-cells. T-cell receptor (TCR) is a heterodimer consisting of an a and a b chain (TCR a/b) or a g and a d chain (TCR g/d). TCR-b is a member of the immunoglobulin super family and a component of the CD3/TCR complex (along with TCR-a). TCRb is expressed by thymocytes and a majority of peripheral (a/b TCR-bearing) T-cells. This antibody does not cross-react with g/d TCR-bearing T-cells.