Department of Paediatrics and Endocrinology, Warsaw Medical University, Warsaw, Poland.
J Physiol Pharmacol. 2009 Nov;60 Suppl 5:77-80.
CTLA-4 gene is one of the strongest locus of genetic susceptibility to autoimmune thyroid diseases. The aim of the present study was to investigate surface expression of CTLA-4 on peripheral T cells in homozygotes AA and GG at position +49 of CTLA-4 gene in children with Hashimoto's thyroiditis and in healthy controls. Blood samples were obtained from 100 children: 45 with Hashimoto's thyroiditis and 55 controls. CTLA-4 exon 1 polymorphism was defined by SSCP and RFLP with BbvI enzyme. T cells were analyzed with three color flow cytometry by Coulter EPICS XL. We found that CTLA-4 expression was significantly lower in the thyroiditis patients than in controls, but CTLA-4 expression in homozygotes GG and AA was comparable. We therefore conclude that decreased expression of CTLA-4 on T cells in children with Hashimoto's thyroiditis is not dependent on polymorphic changes at position +49 of CTLA-4 gene.
CTLA-4 基因是自身免疫性甲状腺疾病最强的遗传易感性基因座之一。本研究旨在探讨桥本甲状腺炎患儿及健康对照者 CTLA-4 基因+49 位 AA 和 GG 纯合子外周 T 细胞表面 CTLA-4 的表达。采集 100 例儿童血样，其中桥本甲状腺炎患儿 45 例，健康对照者 55 例。采用 SSCP 和 BbvI 酶 RFLP 方法对 CTLA-4 外显子 1 多态性进行检测。应用 Coulter EPICS XL 三色流式细胞仪对 T 细胞进行分析。我们发现桥本甲状腺炎患儿 CTLA-4 表达明显低于对照组，但 CTLA-4 在 GG 和 AA 纯合子中的表达无差异。因此我们得出结论，桥本甲状腺炎患儿 T 细胞 CTLA-4 表达降低与 CTLA-4 基因+49 位多态性改变无关。
