增生性瘢痕中基底膜基质对表皮分化成熟和S100A8/A9的影响及其导致成纤维细胞活化的研究

Hypertrophic scar is one of the most common complication of wound healing, which is a focus and difficulty in the field of surgical restoration due to the intricate mechanisms. Epidermis plays an essential role in modulating subjacent connective tissue and wound healing of skin. However, its role in scar formation is not well charted yet. Our previous study shows that S100A8/A9 are highly expressed in the epidermis of human hypertrophic scar tissues compared to normal skin. Reduced hydration up-regulates the expression of many genes including S100A8/A9 in the epidermis, then S100A8/A9 activate dermal fibroblasts. This investigation on dermal fibrosis focusing on keratinocyte supplied a novel idea to explore the mechanism of hypertrophic scar. Adjusting mechanism of keratinocyte in this process has not been elucidated. Due to the critical role of basement membrane matrix on the differentiation and mutation of keratinocyte, we speculate that the basement membrane matrix is implicated in modulating keratinocyte and fibroblast in scar. In this study, we attempt to investigate the effect and pathway of basement membrane matrix on the differentiation and mutation of keratinocytes and activation of dermal fibroblasts through in vitro scar culture model, which provides a novel theoretical and experimental basis to elucidate the formation of hyperplastic scar.

增生性瘢痕作为创面愈合后最常见的并发症之一，相关研究一直是外科修复领域的热点和难点。表皮在调节深部结缔组织和皮肤损伤修复中具有重要作用，但是在瘢痕形成过程中，其调节途径和方式仍不明确。前期研究显示，S100A8/A9的水平在增生活跃的瘢痕表皮中高表达；失水能促使表皮角质形成细胞的众多炎症因子，包括S100A8/A9的表达水平上调，而S100A8/A9将进一步促发成纤维细胞的活化，这种从角质形成细胞出发的真皮纤维化研究为探索增生性瘢痕的发生机制提供了新的思路。但在这个过程中，角质形成细胞的被调控机制还不甚明确。由于基底膜基质对角质形成细胞的分化成熟至关重要，于是我们推测基底膜基质可能在瘢痕角质形成细胞的被调控过程中扮演了重要角色。本研究拟通过建立瘢痕体外培养模型，探究基底膜基质对角质形成细胞分化成熟及真皮成纤维细胞活化的影响及作用途径，这将为阐明增生性瘢痕的形成及发展提供新的理论和实验依据。

目的：通过对增生性瘢痕来源的基底膜及成纤维细胞进行分析，研究基底膜及成纤维细胞在参与瘢痕增生过程中所扮演的角色。.方法：通过制备正常皮肤与增生性瘢痕的脱细胞基质，在电镜下观察基底膜形态、厚度、连续性，比较正常皮肤与增生性瘢痕基底膜的差异；通过在不同来源的脱细胞基质上接种角质细胞，观察角质细胞的迁移分化，研究基底膜对角质细胞迁移分化的影响；通过提取正常皮肤成纤维细胞及瘢痕皮肤成纤维细胞条件培养基，观察角质细胞在不同条件培养基下的迁移与分化，并通过测定成纤维细胞中MMP-1,TIMP-1，bFGF及角质细胞中S100A8,S100A9及CK19的基因表达，研究不同来源成纤维细胞对对角质细胞迁移分化的影响及机制。.结果：增生性瘢痕基底膜增厚、厚薄不均、连续性差；增生性瘢痕基底膜上角质细胞生长不良；增生性瘢痕成纤维细胞减慢角质细胞迁移；’增生性瘢痕成纤维细胞影响角质细胞器官样分化；增生性瘢痕成纤维细胞KGF的表达量为正常成纤维细胞的0.46倍；瘢痕成纤维细胞MMP-1/TIMP-1的表达量均升高，为正常成纤维细胞的3.86倍及2.76倍；在瘢痕成纤维细胞影响下，角质细胞CK19的表达量显著降低，为正常成纤维细胞的0.81倍；在瘢痕成纤维细胞影响下，角质细胞S100A8的表达量无明显变化，S100A9的表达量显著增高，为正常成纤维细胞的2.47倍。.结论：创面伤及基底膜将导致基底膜结构与功能不良，进而导致其上角质细胞分化迁移不良，跨细胞脱水增加，并影响成纤维细胞过度活化；增生性瘢痕中过度活化的成纤维细胞能够通过KGF表达量降低等途径影响角质细胞迁移分化，从人体形成类似正反馈的成纤维细胞叠加活化机制，导致胶原代谢紊乱，产生增生性瘢痕。

内容获取失败，请点击重试