Molecular mechanism of scarless wound healing its application for therapy of epidermolysis bullosa

为了探讨无瘢痕创面愈合的分子机制，并确定其特异的基因/蛋白，即主控基因/蛋白，我们利用差异显示和序列分析基因表达技术，对观察到无瘢痕创面愈合的胎鼠皮肤中的基因表达进行了分析。差异显示分析发现了10多种无瘢痕创面愈合相关基因，包括纤维调素、糖蛋白、HOX和PRX家族、转化生长因子-β、PDGH和EGF等基因。此外，还检测到了几个未知基因。序列分析基因表达分析检测到包括未知基因在内的20多种基因，然而，将每种基因或其重组蛋白的表达载体导入成年小鼠皮肤的伤口并未消除瘢痕形成。因此，本研究中鉴定的每个基因都不是无瘢痕伤口愈合的主控基因。透明质酸在观察到无瘢痕愈合的真皮中特异积聚，提示透明质酸是无瘢痕愈合机制的重要调节剂之一。因此，我们接下来研究了富含透明质酸的环境特异性基因。对含有大量透明质酸的培养的人真皮成纤维细胞进行的系列分析基因表达分析显示，与在无疤痕伤口愈合中检测到的结果相似。共检测到35个富含透明质酸的环境特异性基因。其中七人未知。然而，将这些基因导入受伤的皮肤也没有消除疤痕的形成。这些结果表明，本研究中鉴定的所有基因都不是主控基因，而是无瘢痕愈合的特异性基因。因此，有必要进一步采用新的分析方法和策略来寻找未知的主控基因。

In order to investigate the molecular mechanism of scarless wound healing and identify its specific gene/protein, that is, master gene/protein, we analyzed gene expression in the fetal mouse skin, which scarless wound healing is observed, by differential display and serial analysis gene expression techniques. Differential display analyses revealed that over ten kinds of scarless wound healing-related genes including genes previously reported such as fibromodulin, glycophorin, HOX and PRX families, TGF-beta, PDGH and EGF genes were detected. Furthermore several unknown genes were also detected. Serial analysis gene expression analyses detected over twenty kinds of genes including unknown genes However, introductions the expression vector of each gene or its recombinant protein into the wounds of adult mice skin did not disappear scar formation. Therefore, each gene identified in this study was not master gene of scarless wound healing. Hyaluronic acid is specifically accumulated in the dermis where scarless wound healing is observed, suggesting hyaluronic acid is one of crucial modulator of mechanism of scarless wound healing. Therefore, we next investigated hyaluronic acid rich environment specific genes. Serial analysis gene expression analyses of cultured human dermal fibroblasts containing high amounts of hyaluronic acid revealed similar results to these detected in scarless wound healing. Thirty five hyaluronic acid rich environment specific genes were detected. Seven of them were unknown. Howerver, introduction of these genes into wounded skin also did not disappear scar formation. These results suggest that all genes identified in this study are not master gene but specific gene of scarless wound healing. Therefore, further novel analysis methods and strategies are necessary to find unknown master gene.