METHOD FOR THE DETERMINATION OF DIFFERENT TYPES OF AUTOANTIBODIES RAISED AGAINST TSH RECEPTORS BY SELECTIVE IMMUNOPRECIPITATION, FUSION PROTEINS FOR DETERMINING SUCH A METHOD AND APPLICATION OF LABELED TSH RECEPTOR CHIMERAS IN SUCH A METHOD

摘要

The invention relates to a method for differential diagnostic determination of autoantibodies (TSHR-auto-Ab) raised against TSH receptors (TSHR) in a serum or plasma sample of a patient suffering from a thyroid gland autoimmune disease or when an illness of the said nature is suspected in a patient whereby is selectively determined an amount of at least one type of autoantibody (TSHR-auto-Ab) in a sample selected from (i) stimulating autoantibodies (TSAb), (ii) blocking autoantibodies (TBAb) and/or (iii) neither stimulating nor blocking, non-pathogenic TSHR-auto-Ab, whereby replacement occurs for an aliquot of a liquid sample from a reaction mixture with a solubilized and directly labeled, in particular, enzyme-labeled binding reagent in the form of a labeled rTSHR-chimera, wherein antibodies required for the binding of stimulating and/or blocking autoantibodies (TSAb and/or TBAb) are replaced by substantial sequences of the TSHR from another receptor, react thereby and the complex formed in the reaction consisting of complexes of autoantibody-rTSHR-chimeras is converted into a precipitate. Said complexes are separated out of the liquid phase of the reaction mixture and the amount of label in the precipitate is determined, in addition to labeled rTHSR-chimeras required for the inventive method.