IgG4型甲状腺特异性抗体糖基化修饰在IgG4型桥本甲状腺炎发病机制中的作用

IgG4 HT is a newly recognised subtype of HT which is associated with rapid progress and higher risks of papillary thyroid carcinoma. In our previous study, it has been shown that TgAb IgG4 glycosylation is different in IgG4 HT and non-IgG4 HT, indicating that it might play a role in the pathogensis of IgG4 HT. However, it is only an observational study and the exact function of glycosylation of IgG4 binding to specific thyroid antigens is still unclear. In order to answer this question, we plan to compare the difference of glycosylation on TgAb IgG4 .and TPOAb IgG4 in IgG4 HT and non-IgG4 HT patients by using lectin microassay. In addition, we also intend to confirm the complement activation pathways in thyroid tissue of IgG4 HT. And based on these results, the glycosylation profile of IgG4 thyroid autoantibodies will be changed by glycobiology technology. The interact between different glycosylation profiles of thyroid IgG4 autoantibodies and different complement components will be further studied. These results may provide more evidence about the role of glycosylation on IgG4 thyroid autoantibodies in the pathgenesis of IgG4 HT.

IgG4型桥本甲状腺炎（HT）作为一种新的HT分型，具有临床进展快，易合并甲状腺乳头状癌等特点，本课题组前期研究发现IgG4型HT患者血清中TgAgIgG4和TPOAbIgG4明显高于非IgG4型HT患者，且TgAbIgG4的糖基化修饰水平在IgG4型与非IgG4型HT患者血清中存在差异，提示其可能参与IgG4型HT的发病，但具体机制尚不明确。我们拟利用凝集素芯片技术检测比较IgG4型HT与非IgG4型HT患者血清中的甲状腺特异性抗体IgG4亚型糖基化修饰的差异，进一步在明确IgG4型HT患者甲状腺组织中存在的补体活化途径后，我们还拟通过改变IgG4型甲状腺抗体的糖基化修饰，获得不同糖型的IgG4型甲状腺抗体，研究其对补体活化途径的影响，验证IgG4型甲状腺特异性抗体的糖基化修饰可能通过影响补体系统参与IgG4型HT发病这一假设，为完善IgG4型HT的发病机制奠定理论基础。

IgG4型桥本甲状腺炎（HT）作为一种新的HT分型，具有临床进展快，易合并甲状腺乳头状癌等特点，本课题组前期研究发现IgG4型HT患者血清中TgAgIgG4和TPOAbIgG4明显高于非IgG4型HT患者，且TgAbIgG4的糖基化修饰水平在IgG4型与非IgG4型HT患者血清中存在差异，提示其可能参与IgG4型HT的发病，但具体机制尚不明确。我们拟利用凝集素芯片技术检测比较IgG4型HT与非IgG4型HT患者血清中的甲状腺特异性抗体IgG4亚型糖基化修饰的差异，进一步在明确IgG4型HT患者甲状腺组织中存在的补体活化途径后，我们还拟通过改变IgG4型甲状腺抗体的糖基化修饰，获得不同糖型的IgG4型甲状腺抗体，研究其对补体活化途径的影响，验证IgG4型甲状腺特异性抗体的糖基化修饰可能通过影响补体系统参与IgG4型HT发病这一假设，为完善IgG4型HT的发病机制奠定理论基础。