[Distribution and significance of IgG subclasses of serum antithyroglobulin antibody in Hashimoto thyroiditis].
OBJECTIVE
To evaluate the distribution and significance of IgG subclasses of antithyroglobulin antibody in sera from patients with Hashimoto thyroiditis.


METHODS
Sera from 112 patients with Hashimoto thyroiditis were collected and patients were divided into 3 groups, i. e. hypothyroidism, subclinical hypothyroidism and euthyroidism. Antigen specific ELISA was used to detect the distribution of IgG subclasses of antithyroglobulin antibody.


RESULTS
The positive rates of IgG subclasses of TgAb were IgG1 90.2%, IgG2 58.0%, IgG3 19.6% and IgG4 87.5% respectively. The mean geometric titers of IgG1 in sera from patients with hypothyroidism and subclinical hypothyroidism were 1: 450.8 and 1: 245.5 respectively, both being significantly higher than that with euthyroidism (1:8.7, P < 0.01). The mean geometric titers of IgG2 in sera from patients with hypothyroidism and subclinical hypothyroidism were 1: 37.3 and 1: 3.2 respectively, both being also significantly higher than that with euthyroidism (1: 0.2, P < 0.01 and P < 0.05 respectively) and that with hypothyroidism was significantly higher than that with subclinical hypothyroidism (P < 0.05).


CONCLUSIONS
The distribution of IgG subclasses of antithyroglobulin antibody in sera from patients with Hashimoto thyroiditis was predominantly IgG1, IgG2 and IgG4. High titers of IgG1 and IgG2 implicated the possibility of development from subclinical hypothyroidism to overt hypothyroidism.
Li
Mao-rong
MR
Department of Endocrinology, Peking University First Hospital, Beijing 100034, China.
Guo
Xiao-hui
XH
Gao
Ying
Y
Gao
Yan-ming
YM
Lu
Gui-zhi
GZ
Hui
Yan
Y
Wang
Shu-feng
SF
Shi
Bing-yin
BY
Teng
Wei-ping
WP
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D050031:Hashimoto Disease / Q000097:blood / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification; D008297:Male; D008875:Middle Aged
D001323:Autoantibodies; D007074:Immunoglobulin G; C006606:anti-thyroglobulin