Soluble T-lymphocyte antigen-specific immunoproteins: A progress report

T-cell-derived proteins that bind nominal (non-MHC-associated) antigen specifically (TABM) express V and C region epitopes of the T-cell receptor (TCR) for antigen and have a significant similarity in amino acid sequence to TCR alpha-chain V and C region. The presence of these immunoproteins in human serum and a specific increase in serum TABM in infectious disease, chemical sensitivity, and food intolerance suggest that TABM may impact on pathogenesis through the modulation of cell-mediated immunity, the antigen-specific concentration and delivery of immunoregulatory cytokines such as TGF-beta and elastase, and the induction of the release of substance P by sensory neurons. In this Minireview update, we describe advances in the detection and quantitation of human TABM by monoclonal antibodies, and the association of increased human serum TABM titers in infectious disease, chemical sensitivity, and food intolerance. We suggest that the immunomodulatory mode of action of these immunoproteins may be the antigen-specific focusing of cytokines associated with TABM.