Th17/Treg轴失衡在儿童重型血友病A抑制物产生中的作用研究

Hemophilia A is one inherited bleeding disease with factor VIII deficiency caused by gene mutation，the concentrates replacement is the only effective method to control bleeding, but the inhibitor ineffects it. The inhibitor development is the biggest obstacle in hemophilia A care in the world, the mechnism is not very clear. The imbanlance of Th17/Treg axis plays key role on immune tolerance, and currently,although the relationship between inhibitor development and Regulatory T cell (Treg cell) in mice model has been proved, Th17/Treg axis imbalance hasn't been proved in the inhibitor developmente in hemophilia. We speculate that, there would exist the relationship between the imbalance of Th17/Treg axis and inhibitor development in hemophilia A patients, maintain its balance might prevent the inhibitor development. Our study is to investigate on severe hemophilia A children, to recode the clinical data, monitor the levels of inhibitor and Th17,Treg cells periodically and continuously, to observe the inhibitor development and affect on Th17/Treg axis during the course of hemophilia A children from unexposure to exposure to exogenous VIII factor, try to regulate and maintain Th17/Treg axis balance in FVIII-/- mice to prevent the inhibitor development. Aim is to establish basic and provide the new method for the inhibitor development and provention machanism in hemophilia management.

血友病A是基因突变致凝血因子VIII活性缺乏的遗传性出血性疾病，凝血因子替代治疗可控制出血，但抑制物产生使之失效。抑制物产生目前是血友病A治疗最大阻碍，机制未明；已知Th17/Treg失衡在免疫失耐受中发挥重要作用，近年虽有小鼠实验证实Treg细胞与血友病抑制物产生相关，但抑制物产生是否与Th17/Treg轴失衡有关尚不清。推测，Th17/Treg轴失衡与血友病抑制物产生相关，调整其平衡可防控抑制物。本课题拟对儿童重型血友病A开展连续、规律的抑制物及Th17、Treg监测，动态观察在接触外源性因子后患儿抑制物和Th17、Treg水平变化，应用FVIII-/-鼠体内实验尝试调整Th17/Treg轴平衡预防抑制物产生。应用上述方法来证实Th17/Treg失衡在血友病A抑制物产生中作用，探索调整Th17/Treg轴平衡来防控抑制物，为阐明血友病抑制物发生机制及提出有效防控策略提供理论依据和思路。

本课题按照研究计划探讨了儿童血友病患者FVIII抑制物出现与Th17细胞，调节性T细胞，Th1/Th2极化之间的关系。一共纳入122例儿童血友病患者。通过流式胞内细胞因子分析技术在从血友病病人外周血单核细胞中检测上述4型T细胞的比例。有36例HA的（29.5％）FVIII抑制物阳性（高滴度患者13/36，占36.1％，低滴度抑制物患者23/36，占63.9％）。HA抑制物阳性患者的Treg细胞比例高FVIII抑制物阴性组（7.17±1.47％和6.49±1.32％）（P <0.05）。在FVIII抑制物阳性患者中，高滴度抑制物患者的Tc1细胞比例高于低滴度组（分别为50.46±24.76％及32.23±16.38％）（P <0.05）。高滴度抑制物患者的Th1细胞比例及Th1 / Th2细胞比率有高于低滴度组，但未达到统计学差异（Th1比例分别为25.62±14.23％比16.87±11.50％，p值=0.052；Th1 / Th2比例分别为28.01±31.58％和14.27±11.62％，P =0.067）。我们的研究结果表明，更高的Treg细胞可能与FVIII抑制物在儿科HA的发展相关联。此外，Tc1的可能是一个危险因素，来预测抑制物的严重状况。我们的研究为儿童血友病抑制物的产生提供了一个可能作为预测的指标，并为FVIII抑制物的产生机制提供了新的理论基础，进一步的研究将有助于深入探索FVIII的产生机制，并为发展新的治疗措施提供了理论基础。