Zuo Hai-Bin, Peng Dai-Zhi, Zheng Bi-Xiang, Chen Bo, Liu Xiao-Ling, Wang Yong, Zhou Ling
Institute of Burn Research, Southwest Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical University, Chongqing 400038, China.
Zhonghua Shao Shang Za Zhi. 2011 Feb;27(1):10-5.
To evaluate the effects of mixed grafting of allogeneic PADM and autologous STS on wound healing of full-thickness defect in rats.
Full-thickness defects with size of 6 cm x 4 cm were produced on the back of 12 SD rats, and they were divided into E group (n = 6) and C group (n = 6) according to the random number table. The wounds in E group were grafted with a mix of allogeneic PADM (expansion rate 10: 5) and autologous STS with thickness of 0.2 mm, while those in C group were grafted with autologous STS in the same thickness. The wound healing rate, survival rate, contraction rate, and expansion rate of transplanted skin were observed at post operation week (POW) 2, 3, 4, 6, 8, 12, 20. Tissue samples form wounds and surrounding normal skin were harvested at POW 20 for histopathological observation as follows. The structure of collagen fiber bundle was observed by HE staining, the diameter and gap rate of collagen fiber bundle were also measured. The distribution of type I and III collagen was observed by sircus red staining, and the contents of type I, III collagen and their ratio were also examined. Data were processed with independent samples t test, Levene test, and t' test.
Survival rate of transplanted skin in E group at POW 2 [(76.1 +/- 13.1)%] was obviously lower than that in C group [(94.5 +/- 1.3)%, t' = 3.440, P = 0.018]. Contraction rate of transplanted skin in E, C groups at POW 3 showed significant difference [(34 +/- 8)% vs. (16 +/- 12)%, t = -3.211, P = 0.009]. Compared with those in peri-wound normal skin, collagen fiber bundles in C group showed signs of homogenization, and collagen fibers were thin with irregular arrangement. Collagen fiber structure and arrangement of composite skin in E group were similar to those surrounding normal skin with incomplete degradation of PADM. Diameter of collagen fiber bundle [(9.6 +/- 0.8) microm], gap rate between collagen bundle [(24 +/- 5)%], content of type I collagen [(80.2 +/- 5.4)%] and the ratio of type I to type III collagen (4.3 +/- 1.2) in E group were all increased as compared with those in C group [(7.3 +/- 1.4) microm (t = -3.562, P = 0.005), (17 +/- 4)% (t = -2.760, P = 0.020), (68.1 +/- 8.4)% (t = -2.981, P = 0.014), 2.3 +/- 1.0 (t = -3.204, P = 0.009)], while content of type III collagen [(19.8 +/- 5.4)%] in E group was lower than that in C group [(32.0 +/- 8.4)%, t = 2. 981, P = 0.014]. Above-mentioned indexes of collagen in wound of E group were similar to those of normal skin surrounding the wound.
Allogeneic PADM used as dermal regeneration template is beneficial in improving collagen fiber bundle structure in dermis layer of rats with full-thickness skin wounds when repaired with autologous STS, and it accelerates maturation of regenerative dermal tissue.
评估异体脱细胞真皮基质（PADM）与自体富血小板血浆（STS）混合移植对大鼠全层皮肤缺损创面愈合的影响。
将12只SD大鼠背部制成6 cm×4 cm的全层皮肤缺损创面，按随机数字表法分为实验组（E组，n = 6）和对照组（C组，n = 6）。E组创面移植厚度为0.2 mm的异体PADM（膨化率10∶5）与自体STS混合物，C组创面移植相同厚度的自体STS。分别于术后2、3、4、6、8、12、20周观察创面愈合率、移植皮片成活率、收缩率及膨化率。术后20周取创面及周边正常皮肤组织标本进行组织病理学观察：苏木精-伊红（HE）染色观察胶原纤维束结构，测量胶原纤维束直径及间隙率；天狼星红染色观察Ⅰ、Ⅲ型胶原分布，检测Ⅰ、Ⅲ型胶原含量及比值。数据采用独立样本t检验、Levene检验及t'检验进行处理。
术后2周E组移植皮片成活率[（76.1±13.1）%]明显低于C组[（94.5±1.3）%，t' = 3.440，P = 0.018]。术后3周E、C组移植皮片收缩率差异有统计学意义[（34±8）%比（16±12）%，t = -3.211，P = 0.009]。C组创面胶原纤维束呈均质化表现，胶原纤维细且排列紊乱；E组复合皮胶原纤维结构及排列与周边正常皮肤相似，PADM未完全降解。E组胶原纤维束直径[（9.6±0.8）μm]、胶原束间隙率[（24±5）%]、Ⅰ型胶原含量[（80.2±5.4）%]及Ⅰ/Ⅲ型胶原比值（4.3±1.2）均高于C组[（7.3±1.4）μm（t = -3.562，P = 0.005）、（17±4）%（t = -2.760，P = 0.020）、（68.1±8.4）%（t = -2.981，P = 0.014）、2.3±1.0（t = -3.204，P = 0.009）]，而E组Ⅲ型胶原含量[（19.8±5.4）%]低于C组[（32.0±8.4）%，t = 2.981，P = 0.014]。E组创面胶原上述指标与创面周边正常皮肤相近。
异体PADM作为真皮再生模板，在自体STS修复大鼠全层皮肤创面时，有利于改善创面真皮层胶原纤维束结构，加速再生真皮组织成熟。
