内源干细胞激活和外源功能性细胞移植的纤维环再生研究

Low back pain due to intervertebral disc (IVD) degeneration remains the primary cause of disability worldwide. Intervertebral disc (IVD) herniation, after annulus fibrosus (AF) ruptured, is responsible for the most painful disorders of low back pain. The key question in AF rupture repair is how to enhance the cell number and activity in the ruptured tissue, and how to reconstruct the extracellular matrix, the biological function and structure. The applicant has proved the activation effect of chemoattractant on AF cells in vitro, also has isolated and characterized a functional AF cells subpopulation. The current project will explore the potential and mechanism of endogenous cell homing and functional cell transplantation for AF tissue repair. The motile AF cell subpopulation will be isolated and characterized, through the selective activation effect of chemoattractant. The regulatory mechanism of growth factors for induction of function related phenotype in AF cells will be investigated. Based on the in-depth research experience on IVD organ culture, mechanical stimulation with bioreactor, and annulotomy model, the effect of chemoattractant delivery and functional cell implantation will be screened in IVD organ culture model within mechanical loading bioreactor. Knowledge obtained from the current project will provide insight into more successful and novel regenerative strategies for annulus fibrosus rupture repair, and is of important socioeconomic meaning in prevention of IVD reherniation disease.

椎间盘退变所致下腰痛是世界范围内导致残疾的主要诱因。其中纤维环破裂后引起的椎间盘突出具最高疼痛级别。纤维环修复需解决的关键问题是如何提高缺损组织内的细胞数量和活性，重建胞外基质，生物学功能和结构。申请人前期已证实体外趋化因子对纤维环细胞的激活作用，并分离鉴定出功能性纤维环细胞亚群。本项目拟从激活纤维环內源细胞和外源功能性细胞移植两方面研究纤维环损伤的再生修复。一方面通过趋化因子对纤维环內动力细胞的选择性激活作用，实现对纤维环内活性细胞的分离和鉴定。另一方面对生长因子调节功能性纤维环细胞修复功能的调节机制进行研究。而后基于申请人在椎间盘器官培养，生物反应器力学加载，椎间盘损伤模型方面深入的前期研究，采用器官培养对其修复作用进行体外高仿真筛选验证。研究成果可为纤维环的功能性修复提供理论基础和实验依据，对预防椎间盘突出疾病复发具有重要意义。

椎间盘退变所致下腰痛是世界范围内导致残疾的主要诱因。其中纤维环破裂后引起的椎间盘突出具最高疼痛级别。纤维环修复需解决的关键问题是如何提高缺损组织内的细胞数量和活性，重建胞外基质，生物学功能和结构。本课题研究了趋化因子对纤维环细胞在体外培养模型，器官培养模型和动物模型中的激活作用。采用生长因子TGF-β1诱导退变的纤维环细胞成为功能性纤维环细胞，并对诱变所得的功能性纤维环细胞的修复功能及其调节机制进行了研究。项目研究结果表明趋化因子CCL5对纤维环细胞在体外2D培养有诱导迁移作用，但是在器官培养实验和动物试验中对纤维环细胞的迁移和椎间盘再生的作用并不明显。生长因子诱导的CD146+功能性纤维环细胞作为种子细胞，具有较好的细胞收缩力，其纤维环细胞标志性因子表达水平显著增高。在生物反应器中的椎间盘器官培养结果表明，CD146功能性纤维环细胞具有较好的增殖能力和纤维环胞外基质合成能力，对于纤维环缺损的修复有良好效果。本课题的研究成果为纤维环的功能性修复提供了理论基础和实验依据，对预防椎间盘突出疾病复发具有重要意义。