Background The main issue in cutaneous regeneration is to develop engineered scaffolds based on natural extracellular matrix to promote dynamics of skin progenitor cells and accelerate differentiation into mature keratinocytes. Methods In this study, nanofibrous scaffolds composed of a blend poly (ɛ-caprolactone) (PCL), silk fibroin (SF), soluble eggshell membrane (SESM), and Aloe vera (AV) gel were developed by electrospinning method and human basal cells were used to examine differentiation capacity toward keratinocyte-like cells. For this propose, cells were allocated to four distinct groups; control, PCL/SF, PCL/SF/SESM, and PCL/SF/SESM/AV. In all groups, cells were incubated with differentiation medium. Morphology, composition, hydrophilicity and mechanical features of PCL/SF, PCL/SF/SESM and PCL/SF/SESM/AV nanofibers were studied by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FT-IR), water contact angle and tensile tests. To examine the orientation of basal cells to mature keratinocytes, we performed immunofluorescence analysis by monitoring cytokeratin-19. The expression of genes such as involucrin, keratin-14 and -5 was monitored by real-time PCR assay. Results PCL/SF, PCL/SF/SESM, and PCL/SF/SESM/AV had suitable physic chemical indices and biological activities to be applied as biomimetic scaffolds for the restoration cutaneous tissue. Compared to control, we found an increased basal cell proliferation at 7 and 14 days after plating on scaffolds and reach maximum levels in group PCL/SF/SESM/AV on day 14 (p < 0.05). Electron microscopy showed cell flattening, morphological adaptation. An integrated cell-to-cell connection was generated after cell seeding on scaffolds in all groups. Immunofluorescence imaging showed the ability of basal cells to synthesize cytokeratin-19 in PCL/SF, PCL/SF/SESM, and positive control cells after exposure to differentiation medium. However, these values were less in PCL/SF/SESM/AV compared to other groups. Real-time PCR analysis showed the potency of all scaffolds to induce the transcription of involucrin, keratin-14 and -5, especially involucrin in PCL/SF/SESM/AV group compared to the negative control. Conclusion Modulation of scaffolds with natural biopolymers could enable us to synthesize structures appropriate for cutaneous regeneration.

中文翻译：

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一种用于皮肤组织工程的新型蛋壳膜混合纳米纤维支架。

背景皮肤再生的主要问题是开发基于天然细胞外基质的工程支架，以促进皮肤祖细胞的动力学并加速向成熟角质形成细胞的分化。方法 在本研究中，采用静电纺丝法和人基底细胞制备了由混合聚（ε-己内酯）（PCL）、丝素蛋白（SF）、可溶性蛋壳膜（SESM）和芦荟（AV）凝胶组成的纳米纤维支架。用于检查对角质形成细胞样细胞的分化能力。对于这个提议，单元被分配到四个不同的组；控制、PCL/SF、PCL/SF/SESM 和 PCL/SF/SESM/AV。在所有组中，细胞与分化培养基一起孵育。PCL/SF 的形态、组成、亲水性和机械特性，通过扫描电子显微镜 (SEM)、傅里叶变换红外光谱 (FT-IR)、水接触角和拉伸试验研究了 PCL/SF/SESM 和 PCL/SF/SESM/AV 纳米纤维。为了检查基底细胞向成熟角质形成细胞的方向，我们通过监测 cytokeratin-19 进行了免疫荧光分析。实时荧光定量PCR检测外皮蛋白、角蛋白14和-5等基因的表达。结果PCL/SF、PCL/SF/SESM和PCL/SF/SESM/AV具有合适的理化指标和生物学活性，可作为仿生支架用于修复皮肤组织。与对照组相比，我们发现在支架铺板后 7 天和 14 天基底细胞增殖增加，并且在第 14 天 PCL/SF/SESM/AV 组达到最高水平（p < 0.05）。电镜显示细胞扁平，形态适应。在所有组中的支架上接种细胞后，产生了集成的细胞间连接。免疫荧光成像显示基底细胞在暴露于分化培养基后在 PCL/SF、PCL/SF/SESM 和阳性对照细胞中合成 cytokeratin-19 的能力。然而，与其他组相比，PCL/SF/SESM/AV 中的这些值较少。实时荧光定量 PCR 分析显示，与阴性对照相比，所有支架均能诱导外皮蛋白、角蛋白-14 和 -5 的转录，尤其是 PCL/SF/SESM/AV 组的外皮蛋白。结论 用天然生物聚合物调节支架可以使我们合成适合皮肤再生的结构。免疫荧光成像显示基底细胞在暴露于分化培养基后在 PCL/SF、PCL/SF/SESM 和阳性对照细胞中合成 cytokeratin-19 的能力。然而，与其他组相比，PCL/SF/SESM/AV 中的这些值较少。实时荧光定量 PCR 分析显示，与阴性对照相比，所有支架均能诱导外皮蛋白、角蛋白-14 和 -5 的转录，尤其是 PCL/SF/SESM/AV 组的外皮蛋白。结论 用天然生物聚合物调节支架可以使我们合成适合皮肤再生的结构。免疫荧光成像显示基底细胞在暴露于分化培养基后在 PCL/SF、PCL/SF/SESM 和阳性对照细胞中合成 cytokeratin-19 的能力。然而，与其他组相比，PCL/SF/SESM/AV 中的这些值较少。实时荧光定量 PCR 分析显示，与阴性对照相比，所有支架均能诱导外皮蛋白、角蛋白-14 和 -5 的转录，尤其是 PCL/SF/SESM/AV 组的外皮蛋白。结论 用天然生物聚合物调节支架可以使我们合成适合皮肤再生的结构。实时荧光定量 PCR 分析显示，与阴性对照相比，所有支架均能诱导外皮蛋白、角蛋白-14 和 -5 的转录，尤其是 PCL/SF/SESM/AV 组的外皮蛋白。结论 用天然生物聚合物调节支架可以使我们合成适合皮肤再生的结构。实时荧光定量 PCR 分析显示，与阴性对照相比，所有支架均能诱导外皮蛋白、角蛋白-14 和 -5 的转录，尤其是 PCL/SF/SESM/AV 组的外皮蛋白。结论 用天然生物聚合物调节支架可以使我们合成适合皮肤再生的结构。