EXPRESSION OF 2 T-CELL RECEPTOR-ALPHA CHAINS - DUAL RECEPTOR T-CELLS

Although many T cells carry two in-frame V(alpha) rearrangements, the products of both V(alpha) rearrangements have never been shown simulta neously on the surface of normal cells. With the use of monoclonal ant ibodies to V(alpha)2, V(alpha)12, and V(alpha)24, up to one-third of m ature T cells expressed two V(alpha) chains as part of two functional and independent T cell receptors (TCRs). Thus, the ''one cell, one rec eptor'' rule does not apply to a large subset of alphabeta T cells. Ce lls 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 impo rtant for autoimmunity and alloreactivity.