Qiu Xue-Wen, Wang Jia-Han
Department of Burns, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. E-mail:
Nan Fang Yi Ke Da Xue Xue Bao. 2018 Mar 20;38(3):363-368. doi: 10.3969/j.issn.1673-4254.2018.03.20.
To investigate the efficacy of Lando dermal scaffold for promoting repair of acute full-thickness skin defects in pigs and explore the possible mechanism.
Three 5 cm×5 cm full-thickness skin defects were created on the left dorsal skin (control group) and another 3 on the right dorsal skin (treatment group) of each of 6 Tibetan pigs. The wounds in the treatment group were covered with a bilayer artificial skin (Lando) and the control wounds with vaseline gauze. In both groups, autogenous split-thickness skin were grafted to the wounds 2 weeks later (with the silicone rubber membrane removed before grafting in the treatment group). At 3 days and 2 and 10 weeks after the injury, the wounds were assessed for general condition and contraction, and tissue samples were collected from the wounds to examine the expressions of α-smooth muscle actin (α-SMA) and transforming growth factor-β1 (TGF-β1) using immunohistochemistry and the expressions of MMP-1 and TIMP-1 mRNA using RT-PCR.
At 3 days after the injury, the wounds in the 2 groups showed no significant differences in the results of any examinations. At 2 weeks after the injury, the wounds in the treatment group showed rich and more smooth granulation tissues with more regular wound edges compared with the control wounds. At 2 and 10 weeks after the injury, the wound contraction rates in the treatment group were (30.5∓3.4)% and (39.2∓2.8)%, respectively, significantly lower than the rates of (51.8∓2.6)% (t=-29.840, P=0.000) and (60.7∓2.2)% (t=-50.213, P=0.000) in the control group. At 2 weeks, the wound tissues in the treatment group expressed significantly higher levels of α-SMA (t=15.921, P=0.000) and TGF-β1 (t=29.995, P=0.000) than the control wounds, but at 10 weeks, the expressions of α-SMA (t=-41.823, P=0.000) and TGF-β1 (t=-99.777, P=0.000) in the treatment group were significantly lower than those in the control group. Compared with those in the control group, the expression of MMP-1 mRNA in the treatment group was significantly lower at 2 weeks (t=-45.412, P=0.000) but significantly higher at 10 weeks (t=78.769, P=0.000), and the expression of TIMP-1 mRNA in the treatment group was significantly lower both at 2 weeks (t=-27.064, P=0.000) and at 10 weeks (t=-40.535, P=0.000).
Lando dermal scaffold can promote granulation tissue growth possibly in relation with increased TGF-β1 and decreased MMP-1 expression in the wounds. This scaffold material also reduces wound contraction and lessens scar hyperplasia and contracture after wound healing, probably as a result of decreased α-SMA, TGF-β1, and TIMP-1 and increased MMP-1 expressions.
探讨Lando真皮支架促进猪急性全层皮肤缺损修复的疗效，并探索其可能机制。
选取6只藏猪，每只猪在左侧背部皮肤制造3个5 cm×5 cm的全层皮肤缺损（对照组），右侧背部皮肤制造另外3个（治疗组）。治疗组伤口覆盖双层人工皮肤（Lando），对照伤口覆盖凡士林纱布。两组均在伤后2周进行自体中厚皮片移植（治疗组在移植前去除硅橡胶膜）。在伤后3天、2周和10周，评估伤口的一般情况和收缩情况，并从伤口采集组织样本，采用免疫组织化学法检测α-平滑肌肌动蛋白（α-SMA）和转化生长因子-β1（TGF-β1）的表达，采用逆转录聚合酶链反应（RT-PCR）检测基质金属蛋白酶-1（MMP-1）和基质金属蛋白酶组织抑制因子-1（TIMP-1）mRNA的表达。
伤后3天，两组伤口各项检查结果无显著差异。伤后2周，与对照伤口相比，治疗组伤口肉芽组织丰富、更光滑，伤口边缘更规整。伤后2周和10周，治疗组伤口收缩率分别为（30.5±3.4）%和（39.2±2.8）%，显著低于对照组的（51.8±2.6）%（t=-29.840,P=0.000）和（60.7±2.2）%（t=-50.213,P=0.000）。伤后2周，治疗组伤口组织中α-SMA（t=15.921,P=0.000）和TGF-β1（t=29.995,P=0.000）的表达水平显著高于对照伤口，但伤后10周，治疗组α-SMA（t=-41.823,P=0.000）和TGF-β1（t=-99.777,P=0.000）的表达显著低于对照组。与对照组相比，治疗组MMP-1 mRNA在伤后2周表达显著降低（t=-45.412,P=0.000），但在伤后10周显著升高（t=78.769,P=0.000），TIMP-1 mRNA在伤后2周（t=-27.064,P=0.000）和10周（t=-40.535,P=0.000）表达均显著降低。
Lando真皮支架可促进肉芽组织生长，可能与伤口中TGF-β1表达增加和MMP-1表达降低有关。这种支架材料还可减少伤口收缩，减轻伤口愈合后的瘢痕增生和挛缩，可能是由于α-SMA、TGF-β1和TIMP-1表达降低以及MMP-1表达增加所致。
