三维全层皮肤的生成等效和自动伤人
Summary
The goal of this protocol is to build up a three-dimensional full thickness skin equivalent, which resembles natural skin. With a specifically constructed automated wounding device, precise and reproducible wounds can be generated under maintenance of sterility.
Abstract
In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models reflect the human wound situation better than animal models. Although two-dimensional models are widely used to investigate processes such as cellular migration and proliferation, models that are more complex are required to gain a deeper knowledge about wound healing. Besides a suitable model system, the generation of precise and reproducible wounds is crucial to ensure comparable results between different test runs. In this study, the generation of a three-dimensional full thickness skin equivalent to study wound healing is shown. The dermal part of the models is comprised of human dermal fibroblast embedded in a rat-tail collagen type I hydrogel. Following the inoculation with human epidermal keratinocytes and consequent culture at the air-liquid interface, a multilayered epidermis is formed on top of the models. To study the wound healing process, we additionally developed an automated wounding device, which generates standardized wounds in a sterile atmosphere.
Introduction
皮肤是身体的最大器官。它创建的外部环境和内部器官之间的屏障。此外，在皮肤保护身体免受流体损失，环境影响，伤害和感染和有助于调节体温1。由于其暴露的位置，皮肤往往受机械，热或化学损伤。虽然皮肤通常能够自我修复，多个本地因素如感染，氧合，和静脉充分可导致受损的伤口愈合。伤口愈合也可以通过全身性因素，如肥胖，酒精中毒，吸烟，药物，营养和疾病，如糖 尿病干扰。2
伤口愈合的过程中，可分为3个阶段：（i）该炎性阶段，（ii）所述增殖性和（ⅲ）重塑期。时伤害皮肤，复信号级联开始，从而导致伤口的闭合。3伤后，伤口出血并形成血块。成纤维细胞进入血液凝块并将其与随后被改造多年来新组织取代。
的生物学过程底层皮肤修复的当前理解是有限的。小动物及猪的模型已被用于研究伤口愈合。然而，这些结果不能被直接转移到由于物种特异性差异人类。除了 这些体内模型中 ，伤口愈合的某些方面可以通过经由在体外单层培养的基础上永生化细胞系或原代细胞刮擦模拟伤口的情况进行研究。4这些刮擦模型高度标准化，但不充分反映复合体内生理学5除了二维模型，三维人体皮肤等同物已经开发了用于皮肤病学研究。这些车型的真皮部分是GEnerated使用各种支架包括脱细胞真皮，6胶原水凝胶，7,8-糖胺9或合成材料10采用这些皮肤当量的上皮-间充质相互作用11的作用下，再上皮，成纤维细胞和角化细胞并且所述的蜂窝串扰的不同生长因子的影响进行研究。此外，这些模型是有用的，以获得有关如何成纤维细胞迁移到受伤区域，以及如何趋化因子影响的组织再生的新知识。12
不仅产生的伤口愈合模型本身的是具有挑战性的，而且还建立了高度标准化伤口模型中是有问题的。常见的技巧，营造出伤口划痕试验，13烫伤，14纸带耐磨，15热损伤，吸16水泡，17液氮，18激光器，19 </SUP>手术刀，18 meshers 6和活检拳。20这些方法大多有同样的缺陷。手动实施伤害是难以标准化和多次测试的重现。大小，形状和伤口的深入研究之间变化，从而削弱研究的数据的质量。利用激光对皮肤定义伤人可以比较容易地标准化，但导致一种情况模仿烧伤创面。由激光所施加的热可引起蛋白质变性，血小板聚集或血管收缩，这可导致坏死组织。
在另一种方法，我们开发了一个自动装置伤人（AWD），这使我们能够产生无菌条件下定义和精确的皮肤伤口。伤人的参数，如穿透深度和速度以及钻头的转速可以调节。在这项研究中，我们结合在内部开发的全层皮肤替代物的AWD（英尺SE），其是相当于由Gangatirkar 等人发表的协议。8皮肤等效的真皮层由人真皮成纤维细胞（HDF），它被嵌入在一个I型胶原凝胶。在真皮层，人表皮角化细胞（HEK）是种子。两周内，在空气-液体界面的HEK建立几个重要的细胞层和角质层组成的表皮。除了这种模式的产生，这项研究显示使用AWD的在富时创建定义和精确的伤口。
Protocol
Representative Results
Discussion
体外细胞通常扩展在二维的细胞培养物，其中细胞粘附到塑料表面。然而，这些培养条件没有反映在其中细胞在体内生长的生理立体条件。根据三维的条件下，细胞可以形成天然的细胞 – 细胞和细胞 – 基质的附件和迁移在三维空间。特别是在皮肤伤口愈合的体内状况的相似性枢转以生成有意义数据，细 胞迁移和基质产生的伤口愈合的关键要素。
为了…
Divulgations
The authors have nothing to disclose.
Acknowledgements
The authors thank the Fraunhofer ISC for the collaboration concerning the construction of the automated wounding device. The project was founded by Fraunhofer internal project “Märkte von Übermorgen” (SkinHeal).
Materials
| Name of Material/ Equipment | Company | Catalog Number | Comments/Description |
| Trypsin EDTA (1:250) 0.5 % in DPBS | PAA | L11-003 | 0.05% |
| Dulbecco’s Phosphate Buffered Saline | Sigma | D8537 | |
| Collagen (6 mg/ml in 0,1 % acetic acid) | Produced in house | ||
| Fibronectin Human Protein, Plasma (50 µg/ml) | Life Technologies | 33016-015 | |
| Inserts | Nunc | 140627 | |
| 6 well plate | Nunc | 140685 | |
| 24 well plate | Nunc | 142485 | |
| Microscope slides | R. Langenbrinck | 03-0070 | |
| Fibroblasts culturing (500 ml): | |||
| DMEM, high glucose | Life Technologies | 11965-092 | 89% (445 ml) |
| Fetal bovine serum | Bio & Sell | FCS.ADD.0500 | 10% (50 ml) |
| Penicillin-Streptomycin (10,000 U/mL) | Life Technologies | 15140-122 | 1% (5 ml) |
| Keratinozyten culture medium (500 ml): | |||
| Keratinocyte Growth Medium 2 | Promocell | C-20111 | 89% (445 ml) |
| Keratinocyte Growth Medium 2 SupplementPack | Promocell | C-39011 | |
| Penicillin-Streptomycin (10,000 U/mL) | Life Technologies | 15140-122 | 1% (5 ml) |
| Gel neutralization solution (250 ml): | |||
| Dulbecco’s Modified Eagle Medium, high Glucose Powder with L-Glutamine | PAA | G0001,3010 | 93% (232,5 ml) |
| Chondroitin sulfate sodium salt from shark cartilage | Sigma | C4384-1g | 1% (2,5 ml) |
| Fetal bovine serum | Bio & Sell | FCS.ADD.0500 | 3% (7,5 ml) |
| HEPES | Sigma | H3375-1kg | 3% (7,5 ml) |
| Skin model submers medium (500ml): | |||
| Keratinocyte Growth Medium 2 | Promocell | C-20111 | |
| Keratinocyte Growth Medium 2 SupplementPack | Promocell | C-39011 | |
| Fetal calf serum | Bio & Sell | FCS.ADD.0500 | 5%-2% (25 ml-10 ml) |
| Penicillin-Streptomycin (10,000 U/mL) | Life Technologies | 15140-122 | 1% (5 ml) |
| Skin model air-liquid interface medium (500 ml): | |||
| Keratinocyte Growth Medium 2 | |||
| Keratinocyte Growth Medium 2 Supplement Pack | Promocell | C-39011 | adding only supplements: Insulin, Hydrocortisone, Epinephrine, Transferrin, CaCl2 |
| Penicillin-Streptomycin (10,000 U/mL) | Life Technologies | 15140-122 | 1% (5 ml) |
| CaCl2 (300 mM) | Sigma | C7902-500g | 0,62% (3,1 ml) |
| Histology: | |||
| IHC-Kit DCS SuperVision 2 HRP | DCS | PD000KIT | |
| Vimentin antibody | Abcam | ab92547 | |
| CK14 antibody | Sigma | HPA023040-100µl | |
| CK10 antibody | Dako | M7002 | |
| Filaggrin antibody | Abcam | ab81468 | |
| H&E staining | |||
| Mayer´s Haemalaun | AppliChem | A0884,2500 | |
| Xylol | Sigma Aldrich | 296325-4X2L | |
| Ethanol | Sigma Aldrich | 32205-4X2.5L | |
| HCl | Sigma Aldrich | H1758-500ML | |
| Eosin | Sigma Aldrich | E4009-5G | |
| 2-Propanolol | Sigma Aldrich | I9516-500ML | |
| Mounting Medium | Sigma Aldrich | M1289-10ML |
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