The Production of Monoclonal Antibodies to Human TSH and Their Use in the Design of Immunometric Assays for Serum and Neonatal Blood Spot TSH

The potential for the application of antibodies as analytical and preparative reagents was greatly expanded by the development of techniques for the production of monoclonal antibodies (Kohler and Milstein, 1975, 1976). The properties of monoclonal antibodies are particularly suited to application in immunometric assays and indeed overcome all the major problems associated with conventional antisera. Antibodies of only moderate affinity may be used in sensitive immunometric assays with detection limits up to two orders of magnitude greater than can be achieved in competitive immunoassays with the same antibody (Buchegger et al, 1981). The work of this thesis was concerned with the production of monoclonal antibodies to human TSH and their use in the design of immunometric assays for serum and neonatal blood spot TSH. Chapter 3 deals with the production of a variety of monoclonal antibodies to TSH. These antibodies were characterised in terms of affinity, specificity and isotype. The results indicated that 5H8 and 2G2 may be of extreme practical value in the development of a two-site immunoradiometric assay (IRMA) for TSH. A number of such assays for the measurement of TSH in serum and in neonatal blood spots were then developed using both monoclonal and polyclonal antisera. Chapter 4 seeks to illustrate the clinical role and suitability of the monoclonal-polyclonal serum TSH assay developed in this project. The assay successfully distinguished all cases of untreated primary hypothyroidism as having an elevated serum TSH and all cases of untreated hyperthyroidism as having an undetectable serum TSH (