真皮模板对烧伤患者创面修复过程中细胞凋亡和p53基因表达的影响

The influence of dermal template on the p53 gene expression and apoptosis during wound repairing in burn patients

目的 动态观察应用真皮模板对烧伤创面修复过程中细胞凋亡和p5 3基因表达的影响。 方法 将 2 0例烧伤患者分为试验组 1 1例 ,采用真皮模板 (异体脱细胞真皮基质 )加自体薄皮复合移植修复创面 ;对照组 9例 ,以单纯自体薄皮移植修复创面。两组患者均于术后 1、2、3、4、5周取组织标本。采用原位缺口末端标记法 (TUNEL)和免疫组织化学法分别检测标本中细胞凋亡和p5 3基因的表达。HE染色观察细胞数量的变化。 结果 随着创面的逐渐修复 ,试验组p5 3基因表达逐渐增强 ,在术后第 2、3、4周与对照组比较差异有显著性意义 (P <0.0 5 ),第 4周达高峰。试验组TUNEL结果显示 ,术后 1周 ,成纤维细胞开始凋亡 ,血管内皮细胞凋亡主要发生在第 2、3周。两组凋亡细胞面积百分比比较 ,在第 3、4周差异有显著性意义 (P <0.0 5 )。4周后 ,试验组成纤维细胞和血管内皮细胞数量较对照组减少。 结论 真皮模板与自体薄皮复合移植 ,可诱导p5 3基因表达和促进细胞凋亡 ,并减少瘢痕增生 ,从而改善创面修复质量。

Objective To observe dynamically the influence of the application of dermal template on the p53 gene expression and apoptosis during wound repairing in burn patients. Methods Twenty burn patients were enrolled in the study and were divided into experiment (E, n=11) and control (C, n=9) groups. The escharectomy wounds in patients with 3rd degree burn in E group were covered with dermal template overlain with thin split-thickness autograft, while those in C group were covered with thin split-thickness autograft only . Specimens were harvested from wounds of both groups at 1st, 2nd, 3rd, 4th and 5th post operative week (POW).The P53 expression and the apoptosis were assessed respectively by immunohistochemistry and by TUNEL kit. The change in cell number was observed after HE staining. Results The P53 expression increased gradually along with the wound healing process from 1st to 4th POW, which was significantly higher than that in C group at 2nd, 3rd, and 4th POW (P<0.05) ,and it reached the peak at 4th POW. Fibroblasts underwent apoptosis at 1st POW in E group, while apoptosis of the endothelial cells occurred mainly at 2nd and 3rd POW. There was obvious difference in the rate of apoptosis between the two groups in 3rd and 4th POW (P<0.05). The numbers of fibroblasts and vascular endothelial cells in E group were smaller than those in C group. Conclusion Application of dermal template overlain with thin split-thickness autograft to wounds could induce P53 expression and cell apoptosis, thereby reduce scar formation, resulting in improvement of the quality of wound healing.