Expression of Two T Cell Receptor α Chains: Dual Receptor T Cells

Although many T cells carry two in-frame V α rearrangements, the products of both V α rearrangements have never been shown simultaneously on the surface of normal cells. With the use of monoclonal antibodies to V α 2, V α 12, and V α 24, up to one-third of mature T cells expressed two V α chains as part of two functional and independent T cell receptors (TCRs). Thus, the "one cell, one receptor" rule does not apply to a large subset of αβ T cells. Cells that belong to this dual TCR subset may be specific for a broader range of antigens than cells with a single receptor, which may be important for autoimmunity and alloreactivity.