In this report we describe the characteristics of auto-antibodies to bovine TSH (bTSH) detected in the serum of 2 females among 102 patients with Graves' disease. These patients had never been injected with bTSH. One patient had high LATS activity and high bTSH binding activity after isotope therapy. The other patient showed no detectable LATS activity. Interestingly, the antibody showed a specifically high binding activity for the labelled TSH preparation purified by receptor. The auto-antibody could be demonstrated by the double antibody method, polyethylene glycol method, and by gel-filtration. The antibody was polyclonal immunoglobulin G (IgG). Because the binding of [125I]bTSH with the patient's antibody was inhibited by pituitary extracts from mammalian species other than human, this antibody may cross-react with bovine, rat, dog, rabbit and whale TSH.
The reaction of LATS activity with Staphylococcal Protein A, a specific binding protein with the Fc part of human IgG(1), IgG(2) and Ig(4), was examined. When IgG(1), IgG(2) and Ig(4) subclasses were removed from LATS positive sera or LATS-IgG fractions by affinity chromatography on Protein A-Sepharose, LATS activity decreased. Almost all LATS activity was found in the fraction that reacted with Protein A. It is suggested that LATS has an expression of a very distinct immunoglobulin G structure, and that LATS activity is distributed mainly in the fraction containing IgG(1), Ig(2) and Ig(4) in LATS positive serum;
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.