腺相关病毒载体（AAV）介导高表达Hepcidin治疗非输血依赖性地中海贫血鼠模型铁过载的作用及机制研究

Thalassemia is inherited chronic hemolytic anemia caused by globin gene defects. Secondary iron overload in the viscera function damage is the serious complications. Our works have proved that thalassemic patients have a high burden of iron overload in our country, especially in the viscera iron overload is obvious. Hepcidin is a recently discovered metabolic regulation genes, and plays an important role in the iron metabolism. We propose to choose a novel adeno-associated viral vectors serotype 9(AAV9)carrying Hepcidin gene to treat the iron overload mice model. Through examining iron metabolism index, viscera iron concentration, mice survival, we will observe whether the AAV9 vector-medicated Hepcidin protein overexpression should significantly reduce iron overload condition, and screen the appropriate dose, then evaluate the safety of the AAV9 treatment. Further in non-transfusion-dependent mice model, through the detection of the iron deposit, flow cytometry technology determination of red blood cell survival, Western Blot method, we try to figure out the effect of the AAV vector-medicated Hepcidin protein overexpression in the reduction of iron overload and the amelioration of the anemia symptoms, and explore its mechanisms.This study may provide more experiment data for the gene therapy of iron overload in non-transfusion-dependent thalassemia.

地中海贫血（地贫）是一种珠蛋白基因缺陷所致的慢性溶血性疾病，继发性铁过载所导致脏器功能损害是其严重的并发症。我们前期研究表明中国地贫患者铁过载状况严重，尤以脏器铁过载明显。Hepcidin是新近发现的铁代谢调节基因，在人体内铁代谢中起重要的核心作用。本课题拟将重组腺相关病毒载体(AAV9)携带Hepcidin基因导入普通小鼠铁过载模型体内，通过检测铁代谢指标、脏器铁浓度、小鼠存活情况等，观察高表达Hepcidin是否减轻鼠模型铁过载状况并筛选适宜剂量，评价其安全性。进一步以非输血依赖性地贫鼠模型为研究对象，通过检测铁沉积、流式细胞技术测定红细胞生存、Western Blot等方法，评价重组AAV9介导高表达Hepcidin在非输血依赖性地贫鼠模型体内减轻铁过载状况、改善贫血的作用，并探讨其机制，为地贫铁过载的基因治疗提供新思路。

地中海贫血（地贫）是一种珠蛋白基因缺陷所致的慢性溶血性疾病，继发性铁过载所导致脏器功能损害是其严重的并发症。我们前期研究表明中国地贫患者铁过载状况严重，尤以脏器铁过载明显。Hepcidin 是新近发现的铁代谢调节基因，在人体内铁代谢中起重要的核心作用。本课题拟将重组腺相关病毒载体(AAV9)携带Hepcidin 基因导入普通小鼠铁过载模型体内，观察高表达Hepcidin 是否减轻鼠模型铁过载状况评价并评估其安全性。进一步以非输血依赖性地贫鼠模型为研究对象，评价重组AAV9 介导高表达Hepcidin 在非输血依赖性地贫鼠模型体内减轻铁过载状况作用及机制。研究结果证实： 重组AAV9 载体可有效介导hamp基因在铁过载小鼠肝脏细胞中长期稳定表达，并且重组AAV9 载体在体内无明显毒副反应；在非输血依赖性地贫鼠模型中重组AAV9 载体介导的高表达Hepcidin可通过降低十二指肠的Ferroportin蛋白浓度，抑制肠道铁吸收，从而减少血液循环系统中铁浓度，实现调控铁过载的效应，这为地贫铁过载的基因治疗提供了实验基础及临床治疗新思路。