The Role of Anti-Serpin B13 Autoantibody as a Biomarker of Slower Progression in Type 1 Diabetes Mellitus

摘要 负责预防1型糖尿病（T1 D）的机制尚未完全了解。 我们的研究表明，一个年轻的T1 D倾向的非肥胖糖尿病（NOD）小鼠的子集， 蛋白酶抑制剂丝氨酸蛋白酶抑制剂B13的自身抗体（AA）水平升高，这种反应 与预防早发性糖尿病有关。丝氨酸蛋白酶抑制剂B13单克隆抗体的实验 自身抗体（mAbs）通过显示抗丝氨酸蛋白酶抑制剂活性是一种 它是预防糖尿病的生物标志物，也是疾病预防过程的积极贡献者。 具体地说，我们发现注射丝氨酸蛋白酶抑制剂B13单克隆抗体可以阻止NOD中的胰岛相关炎症， 模型，并在正常Balb/c小鼠中诱导每只动物产生约80个胰岛。我们 对从比利时糖尿病登记处获得的人类样本的额外分析表明， 早发性T1 D与低丝氨酸蛋白酶抑制剂B13 AA产生相关，表明呈反比关系 丝氨酸蛋白酶抑制剂免疫反应和临床糖尿病的发展之间的关系。重要的是我们的 对TrialNet安慰剂受试者的分析表明，基线serpin抗体与较慢的 近期发病的T1 D儿童中残余β细胞功能下降。总之，我们在 小鼠和人类一致认为，对丝氨酸蛋白酶抑制剂B13的抗体应答促进有益的 T1 D的结果。 为了继续将我们的发现应用于人类，我们建议对T1 D风险个体进行研究。 他们被跟踪到疾病发作的时候。要顺利完成这个项目， 对从大约600名个体中获得的血清样品进行了检查， 1型糖尿病的预防试验（DPT-1）。在目标1中，我们将检查高， 中等、中等和低T1 D风险，并评估其与SERPIN B13的血清学结合活性， 基线。在目标2中，我们将比较受试者之间的血清结合活性， 与未患糖尿病的人相比，进展为糖尿病的T1 D风险更高。最后，在Aim 3中 我们将评估丝氨酸蛋白酶抑制剂B13抗体对胰岛β细胞增殖的影响， 从人类身上。Serpin AAs将使用在我们的研究中开发的基于Luminex的技术进行检测。 实验室，并与Benaroya的试验验证中心（CAV）合作进行验证 研究院 这项研究将有助于阐明对丝氨酸蛋白酶抑制剂分子的体液免疫是否可以作为生物标志物 在人类自身免疫性炎症的情况下， 患者这也将有助于我们验证丝氨酸蛋白酶抑制剂B13单克隆抗体可以治疗 通过增强对丝氨酸蛋白酶抑制剂的免疫力而有益。

Abstract The mechanisms responsible for protection against type 1 diabetes (T1D) are not completely understood. Our studies demonstrated that a subset of young T1D-prone non-obese diabetic (NOD) mice have elevated levels of autoantibodies (AAs) to the proteinase inhibitor serpin B13, and that this response correlated with protection from early onset diabetes. Experiments with serpin B13 monoclonal autoantibodies (mAbs) extended these observations by showing that anti-serpin activity is both a biomarker of protection from diabetes and an active contributor to the disease-prevention process. Specifically, we found that injecting serpin B13 mAb impeded islet-associated inflammation in the NOD model and induced the generation of approximately 80 islets per animals in normal Balb/c mice. Our additional analysis of human samples obtained from the Belgian Diabetes Registry demonstrated that early onset T1D is associated with low serpin B13 AA production, suggesting an inverse relationship between the serpin immunological response and the development of clinical diabetes. Importantly, our analysis of TrialNet placebo subjects indicated that baseline serpin antibody is associated with slower decline in residual beta cell function in children with recent onset T1D. Together, our findings in the mouse and humans consistently suggested that antibody response to serpin B13 promotes beneficial outcomes in T1D. To continue translating our findings to humans, we propose a study of individuals at risk for T1D who were followed to the time of disease onset. The successful completion of this project will require examination of serum samples obtained from approximately 600 individuals during their enrollment in the Diabetes Prevention Trial for Type 1 Diabetes (DPT-1). In Aim 1, we will examine subjects with high, intermediate, modest, and low risk for T1D and assess their serological binding activity to SERPIN B13 at baseline. In Aim 2, we will compare serum-binding activities between subjects with an intermediate-to- high risk for T1D who progressed to diabetes versus those that remained diabetes-free. Finally, in Aim 3 we will assess impact of antibodies to serpin B13 on beta cells proliferation in pancreatic islets isolated from humans. Serpin AAs will be detected with a Luminex-based technology that was developed in our laboratory and validated in collaboration with the Core for Assay Validaion (CAV) at the Benaroya Research Institute. This study will help to clarify whether humoral immunity to serpin molecules could be a biomarker of homeostasis resulting in improved beta cell health in the setting of autoimmune inflammation in human patients. It will also help us to verify the hypothesis that serpin B13 mAbs can be therapeutically beneficial by enhancing immunity against serpins.