Premium
Characterization of thyroglobulin epitopes in Sardinian adults and juveniles with Hashimoto’s thyroiditis: evidence against a major effect of age and genetic background on B‐cell epitopes
Author(s) -
Latrofa Francesco,
Ricci Debora,
Vitti Paolo,
Prinzis Alessia,
Cambuli Valentina Maria,
Ghiani Mariangela,
Pilia Sabrina,
Carta Daniela,
Loche Sandro,
Pinchera Aldo,
Mariotti Stefano
Publication year - 2010
Publication title -
clinical endocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 147
eISSN - 1365-2265
pISSN - 0300-0664
DOI - 10.1111/j.1365-2265.2009.03748.x
Subject(s) - epitope , thyroglobulin , thyroiditis , medicine , antibody , endocrinology , recombinant dna , microbiology and biotechnology , biology , immunology , thyroid , genetics , gene
Summary Background Using recombinant human monoclonal thyroglobulin antibodies expressed as Fab molecules (TgAb‐Fab), we have recently confirmed the restriction of Tg epitopes in Hashimoto’s thyroiditis (HT). Objective To investigate Tg epitopes of serum TgAb in HT adults and HT juveniles from a geographically isolated area (Sardinia). Design and Patients Serum TgAb of 39 Sardinian HT adults, 53 Sardinian HT juveniles and 45 non‐Sardinian HT adults were evaluated. The binding of serum TgAb to Tg in ELISA was inhibited by four recombinant human TgAb‐Fab, identifying Tg epitopic regions A–D. The percentage of Tg binding inhibition was calculated comparing the binding of serum TgAb in presence of each TgAb‐Fab with that in its absence. Results In the whole cohort of 137 patients, A region TgAb‐Fab induced the highest levels of inhibition (55·3 ± 17·8%) (mean ± SD). Lower levels of inhibition were induced by TgAb‐Fab of regions B (27·8 ± 25·8%), C (26·8 ± 24·6%) and D (17·5 ± 18·4%). In Sardinian HT adults inhibition by TgAb‐Fab of regions A, B and C were comparable to Sardinian HT juveniles; the marginal D region TgAb‐Fab induced a slightly higher inhibition (22·1 vs. 13·8%; P = 0·034) in the former than in the latter group. In Sardinian and non‐Sardinian HT adults inhibitions by the four TgAb‐Fab were similar. Conclusions In HT, the Tg epitope pattern of serum TgAb was similar in juveniles and adults from a geographically restricted area and in two adult populations from different geographical areas. Thus, in HT, neither age nor genetic background appear to influence B‐cell epitopes.