Partial amino acid sequence of monoclonal extracellular antigen-specific T cell proteins

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.

Measurement of T-cell-derived antigen binding molecules and immunoglobulin G specific to Candida albicans mannan in sera of patients with recurrent vulvovaginal candidiasis

Immunoglobulin G (IgG) and T-cell-derived antigen binding molecules (TABM) specific to whole Candida extract and to Candida-derived mannans prepared by both the cetryltrimethylammonium bromide (CTAB) and alkaline degradation (PEAT) methods were measured in the sera of women with vulvovaginal candidiasis and controls. In the patients there were significantly higher levels of IgG to both CTAB and PEAT mannans and of TABM to CTAB mannan. TABM specific to CTAB mannan was purified from the serum of a patient with a high titer of this TABM. The purified TABM bound specifically to CTAB mannan and to other yeast and mold extracts. This TABM preparation was associated with transforming growth factor beta2 (TGF-beta2), and on specific binding to mannan there was a marked increase in the level of detectable TGF-beta2. This increase in TGF-beta2 level was critically dependent on the relative concentrations of the purified TABM and mannan, being smallest when either was in excess. The TABM specific to CTAB mannan was also shown to inhibit Candida-stimulated gamma interferon production. The results suggest that CTAB mannan-specific TABM may increase susceptibility to vulvovaginal candidiasis in association with a shift in the immune response to the Th2 type.

Clinical and immunological responses in subjects sensitive to solvents

Twenty patients proved sensitive to a 15-min exposure to 15 ppm toluene. We assessed patients neuropsychologically before and after toluene exposure, and they had impaired cognitive functioning characterized by a deterioration in short- and long-term memory and psychomotor coordination. We measured total immunoglobin G and T-cell antigen-binding molecules against an antigen prepared by conjugation of para-aminobenzoic acid to human serum albumin in 20 patients and 16 controls. There was no significant difference in the immunoglobulin G levels to the antigen in the 2 groups, but the levels of T-cell antigen-binding molecules against the para-aminobenzoic acid conjugated to human serum albumin were elevated significantly in subjects sensitive to toluene. We also found significant associations between T-cell antigen-binding molecule levels and (a) decreased performance on the STROOP (Colour Word) test, (b) a shift in focal length following toluene exposure, (c) clinical assessment of disability, and (d) longer histories of chemical exposure. The measurement of T-cell antigen-binding molecules against chemical haptens may be valuable in the assessment of patients who are sensitive to chemicals.