对无瘢痕修复鼠标胎儿皮肤模型
Summary
During mammalian development, early gestational skin wounds heal without a scar. Here we detail a reliable and reproducible model of fetal scarless wound healing in the cutaneous dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.
Abstract
Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs across species but is age dependent. The transition from a scarless to scarring phenotype occurs in the third trimester of pregnancy in humans and around embryonic day 18 (E18) in mice. However, this varies with the size of the wound with larger defects generating a scar at an earlier gestational age. The emergence of lineage tracing and other genetic tools in the mouse has opened promising new avenues for investigation of fetal scarless wound healing. However, given the inherently high rates of morbidity and premature uterine contraction associated with fetal surgery, investigations of fetal scarless wound healing in vivo require a precise and reproducible surgical model. Here we detail a reliable model of fetal scarless wound healing in the dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.
Introduction
胎儿皮肤伤口愈合迅速，scarlessly直到怀孕后期1。胎疤痕伤口修复的特征在于正常组织结构和功能的再生。从瘢痕瘢痕表型的转变发生在怀孕的人类和周围18天胚胎（E18）小鼠2,3孕晚期。相较于成人，胎儿伤口修复的特征在于快速上皮，结缔组织沉积和成纤维细胞的迁移。
在早期胎儿发育许多研究都提供了可能的解释为瘢痕伤口愈合的现象。炎症是成人创面修复的一个基本组成部分;然而，胎儿伤口的特征在于缺乏急性炎症4。这是否是免疫系统的过程中的胎儿阶段官能不成熟的结果仍不清楚。最近的一项研究表明，在丰富，垫差异urity，和肥大细胞在E15与E18的胎儿皮肤的功能可以负责从瘢痕表型的转变中，至少在小鼠3。其他的研究断定，在性能和丰富的胎儿和成人伤口巨噬细胞的差异是负责正常的细胞外基质（ECM）的过程中胎儿创伤修复5的改革。
胎儿和成人发育期间差异在环境因素也可能影响伤口修复。龙雅葛和他的同事发现，从胎儿伤口液具有较高水平的透明质酸刺激活性相比，无成人伤口流体6。因此，更高水平的透明质酸，糖胺聚糖促进有利于细胞运动和增殖的微环境，在胎儿的伤口环境的可负责的瘢痕的表型在早期胎儿发育看见。其他线路的证据指向的一个事实，即在羊升伤口环境相对低氧血症和淹没在无菌羊水丰富的生长因子，7。然而，没有明确的答案已提供用于胚胎发育过程中的关键事件或因素触发从瘢痕再生纤维变性修复的过渡。
理解的机制负责在胎儿无瘢痕愈合就必须精确和可再现的模型。在这里，我们详细胎儿无瘢痕愈合的E16.5（无疤痕）和E18.5（疤痕）的小鼠胚胎的背部可再现的模型。此外，该模型的微小变化可用于执行许多进一步的研究，如胎儿的伤口和皮肤8,9的基因表达分析。鉴于精确定时怀孕是此无瘢痕伤口愈合模式成功的关键再演，我们对超排定时怀孕也详细我们的协议。
Protocol
Representative Results
Discussion
这里介绍的手术协议描述的小鼠胎儿无瘢痕愈合首次出版于2006年，由我们的实验室10的切除模式。除了 切除伤人11等建立模型，对小鼠胎儿无瘢痕愈合的切口车型存在，以及12,13。胎儿无瘢痕愈合猴，羊，兔，负鼠，老鼠和调查的报道14-17。然而，小鼠表现为探索胎儿无瘢痕愈合的理想模型，由于其相对较低的按日补助笼的成本和良好的特点的基因组。此外，?…
Divulgations
The authors have nothing to disclose.
Acknowledgements
这项工作是由美国国立卫生研究院资助R01 GM087609（以HPL），从英格丽·莱和比尔舒荣誉安东尼舒（以HPL），美国国立卫生研究院资助U01 HL099776（以MTL）的礼物，在Hagey实验室拨款部分支持小儿再生医学和橡树基金会（MTL来和HPL）。 GGW是由斯坦福大学医学院，斯坦福大学医学院科学家培训项目的支持，并NIGMS培训资助GM07365。 MSH是由CIRM临床研究员培训资助TG2-01159支持。 WXH是从萨尔诺夫心血管基金会的资助支持。
Materials
| Name of Material/Equipment | Company | Catalog Number | Comments/Description |
| 7-O MONOSOF Suture | eSuture | SN-1647G | |
| Surgical Forceps | Kent Scientific | INS650916 | |
| Micro-scissors | Kent Scientific | INS600127 | |
| Autoclip 9mm | Texas Scientific Instruments | 205060 | |
| Insulin Syringe | Thermo Fisher Scientific | 22-272-382 | |
| Black Pigment | AIMS | 242 | |
| BD Safety-Lok 3ml Syringe | BD Biosciences | 309596 | |
| Phosphate Buffered Saline | Life Technologies | 10010-049 | |
| OPMI-MD Surgical Microscope | Carl Zeiss Surgical Inc | ||
| Pregnant Mares Serum (PMS) | Millipore | 367222 | |
| Human Chorionic Gonadotropin (HCG) | Sigma-Aldrich | CG10 | |
| Povidone Iodine Prep Solution | Dynarex | 1415 | |
| Nair (depilatory cream) | Church and Dwight Co. | 22600267058 |
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