Abstract

In order to delineate the important antigenic determinants, human thyroiditis and rabbit antihuman thyroglobulin sera have been tested against native and modified thyroglobulins. Reduction or trypsinization of thyroglobulin produced a substantial diminution of its reactivity with rabbit antisera and almost abolished its reaction with thyroiditis sera. Thyroglobulin transiently exposed to 8 M urea retained the ability to precipitate with rabbit antibodies but did not precipitate with human antibodies. It was possible to demonstrate, however, that urea-treated thyroglobulin formed soluble complexes with human antibodies. No new antigenic sites for the human serum were produced by any of the modifications. The soluble complexes formed between rabbit and human antibodies and native thyroglobulin have been compared by sucrose gradient ultracentrifugation. The complexes formed with human antibodies were more homogeneous than those formed with rabbit antibodies at a given antibody-antigen ratio. It is concluded that human antithyroglobulin antibodies possess a more restricted range than rabbit antibodies. All of the antigenic determinants active in human autoimmunization are exposed on native thyroglobulin, and the sites with the highest affinities are destroyed by modification of the secondary and tertiary structure of the molecule.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.