骨髓间充质干细胞对瘢痕成纤维细胞作用的机制研究

Mechanism of mesenchymal stem cells affecting hypertrophic scar fibroblasts

[目的]观察骨髓间充质干细胞(BM-MSCs)对增生性瘢痕成纤维细胞(HSFB)的影响及其机制研究,为增生性瘢痕的治疗提供实验基础。[方法]分离培养人BM-MSCs和HSFB,制备BM-MSCs条件培养液(CM),分别于12、24和48 h收集CM。将不同时间点收集的CM孵育体外培养的HSFB 24 h,并与空白对照组比较,成纤维细胞的增殖情况采用MTT进行检测,胶原及TGF-β/Smad信号通路的相关基因采用RT-PCR进行检测。[结果]在24、48 h收集的BM-MSCs CM,与对照组相比对HSFB的增殖具有明显的抑制作用(P<0.01),并显著降低了Ⅰ型和Ⅲ型胶原的表达;MSCs在转录水平能显著降低TGF-bRI和TGF-bRII的表达,却能增强Smad7基因的表达,然而,对Smad 2、Smad 3、Smad 4的表达没有影响。[结论]MSCs可以通过对HSFB TGF-β/Smad信号通路的抑制作用,进而达到治疗或抑制增生性瘢痕的目的,为以细胞疗法为治疗策略减轻瘢痕的方法提供了新的理论支持。

[Objective]To study the effect and mechanism of action of bone marrow mesenchymal stem cells（ BM-MSCs）on hypertrophic scar fibroblasts（ HSFBs）. [Method]BM-MSCs and HSFBs were isolated and cultivated. Then,conditioned media（ CM） from MSCs was collected at 12 h,24 h,and 48 h,and used to treat HSFBs. HSFB proliferation was determined by MTT assay,and RT-PCR was used to measure the mRNA expression levels of collagen and TGF-β /Smad signaling. [Result]BM-MSC CM collected at 24 h and 48 h significantly inhibited the proliferation of and collagen synthesis in HSFBs as compared to the control group（ P〈0. 01）. In addition,BM-MSCs exhibited reduced expression of both TGF-β RI and RⅡ and increased expression of Smad 7 at the transcriptional level. However,BM-MSC CM did not influence the expression of Smad 2Smad 3 and Smad 4.[Conclusion]BM-MSCs could potentially be used in the treatment and /or prevention of hypertrophic scars by a mechanism involving TGF-β /Smad signaling and may provide new theoretical support for cell therapy to reduce cutaneous scarring.