Standardisation des immunodosages de la TSH : production de nouveaux calibrateurs et harmonisation des tests

Discordances among TSH measurements have been long documented over the past two decades but are still poorly understood at the molecular level. This review presents an overview of TSH structural polymorphism in the pituitary stock compared to various recombinant preparations and the circulating hormone. Comparative immunochemical analysis of pituitary TSH and a recombinant hormone produced in mammalian cells demonstrate that several epitopes are differentially expressed as a result of alteration in glycosylation. Consequently, variable antibody recognition may be generated between blood samples and internal calibrators among assays. There is thus a need for designing new calibrators which best mimick circulating TSH for developing harmonization of TSH tests.