沉默受体树突状细胞Rel-A基因诱导大鼠角膜移植免疫耐受的作用及机制研究

Immune rejection is still the main cause of corneal transplant failure, to thoroughly overcome the rejection，getting immature dendritic cells (DC) to induce immune tolerance is an ideal method. TLRs (Toll - like receptors)/the NF-kappa B (nuclear factor kappa B) pathway activation can promote DC maturation and autoimmune destruction. Rel - A phosphorylation is the main form of the NF-kappa B showing biological functions, so we can intervene the Rel - A expression to influence its phosphorylation, decrease the activity of the NF-kappa B to tolerance DC, induction of immune tolerance. We have found that the TLR2 expression enhancement, along with the deterioration of the rat corneal transplantation immune rejection, on the basis of using RNA interference technology, screening effective inhibition of Rel - A expressing siRNA sequences, silence Rel - A gene of DC, to tolerance the DC, at the same time, the DCs having a donor antigen to tolerance are injected into rat corneal transplantation model, explore the effect and mechanism of their induced rat corneal transplantation immune tolerance , and further clarify the role of TLR2 in corneal immune rejection. For providing theoretical and experimental basis on clinical treatment of corneal immune rejection.

免疫排斥反应仍然是角膜移植手术失败的最主要原因，通过干预树突状细胞（DC）诱导免疫耐受是彻底克服排斥反应的理想方法。TLRs（Toll-like receptors）/NF-κB(nuclear factor kappa B)通路的激活可促进DC的成熟而破坏免疫耐受。Rel-A磷酸化是NF-κB发挥生物学功能的主要形式，因此推测可以通过干预Rel-A，影响其磷酸化，减弱NF-κB的活性获得致耐受DC，诱导免疫耐受。本研究在前期发现TLR2随大鼠角膜移植免疫排斥反应的加重而表达增强的基础上，采用RNA干扰技术，筛选高效抑制Rel-A表达的siRNA序列，沉默受体DC的Rel-A基因，以获得致耐受DC，同时将该负载有供体抗原的致耐受DC注入大鼠角膜移植模型，探讨其诱导大鼠角膜移植免疫耐受的效果和作用机制，并进一步明确TLR2在角膜免疫排斥反应中的作用，为临床治疗角膜免疫排斥提供理论和实验依据。

本课题按计划执行，过程顺利，成功体外诱导了具有良好生物活性的大鼠髓系来源树突状细胞。通过构建表达shRNA-Rel-A的慢病毒载体，成功获得具有稳定状态和致耐受性能的未成熟DC，明确了TLR2/MyD88/NF-κB通路在角膜移植免疫排斥反应中的作用。阐明了Rel-A基因修饰并负载供体抗原的受体未成熟DC治疗角膜移植免疫排斥的效果及机制，为角膜移植排斥的治疗提供了新方法、新思路。并发表SCI论著2篇，中文核心期刊论著1篇；培养研究生4名。