Sharma Vaibhav, Patel Nimesha, Kohli Nupur, Ravindran Nivedita, Hook Lilian, Mason Chris, García-Gareta Elena
RAFT Institute of Plastic Surgery, Mount Vernon Hospital, Northwood, HA6 2RN, UK. Department of Biochemical Engineering, University College London, Gower Street, London, WC1E 6BT, UK.
Biomed Mater. 2016 Sep 2;11(5):055001. doi: 10.1088/1748-6041/11/5/055001.
Dermal scaffolds promote healing of debilitating skin injuries caused by burns and chronic skin conditions. Currently available products present disadvantages and therefore, there is still a clinical need for developing new dermal substitutes. This study aimed at comparing the viscoelastic, physical and bio-degradable properties of two dermal scaffolds, the collagen-based and clinically well established Integra(®) and a novel fibrin-based dermal scaffold developed at our laboratory called Smart Matrix(®), to further evaluate our previous published findings that suggested a higher influx of cells, reduced wound contraction and less scarring for Smart Matrix(®) when used in vivo. Rheological results showed that Integra(®) (G' = 313.74 kPa) is mechanically stronger than Smart Matrix(®) (G' = 8.26 kPa), due to the presence of the silicone backing layer in Integra(®). Micro-pores were observed on both dermal scaffolds, although nano-pores as well as densely packed nano-fibres were only observed for Smart Matrix(®). Average surface roughness was higher for Smart Matrix(®) (Sa = 114.776 nm) than for Integra(®) (Sa = 75.565 nm). Both scaffolds possess a highly porous structure (80-90%) and display a range of pore micro-sizes that represent the actual in vivo scenario. In vitro proteolytic bio-degradation suggested that Smart Matrix(®) would degrade faster upon implantation in vivo than Integra(®). For both scaffolds, the enzymatic digestion occurs via bulk degradation. These observed differences could affect cell behaviour on both scaffolds. Our results suggest that fine-tuning of scaffolds' viscoelastic, physical and bio-degradable properties can maximise cell behaviour in terms of attachment, proliferation and infiltration, which are essential for tissue repair.
真皮支架可促进由烧伤和慢性皮肤疾病引起的顽固性皮肤损伤的愈合。目前市面上的产品存在缺点，因此临床上仍需要开发新的真皮替代物。本研究旨在比较两种真皮支架的粘弹性、物理和生物可降解特性，一种是基于胶原蛋白且临床应用成熟的Integra(®)，另一种是我们实验室研发的新型基于纤维蛋白的真皮支架Smart Matrix(®)，以进一步评估我们之前发表的研究结果，该结果表明Smart Matrix(®)在体内使用时细胞流入量更高、伤口收缩减少且疤痕形成较少。流变学结果显示，由于Integra(®)中存在硅胶背衬层，其机械强度比Smart Matrix(®)更高（Integra(®)的储能模量G' = 313.74 kPa，Smart Matrix(®)的储能模量G' = 8.26 kPa）。两种真皮支架均观察到微孔，不过仅在Smart Matrix(®)中观察到纳米孔以及紧密堆积的纳米纤维。Smart Matrix(®)的平均表面粗糙度（Sa = 114.776 nm）高于Integra(®)（Sa = 75.565 nm）。两种支架均具有高度多孔的结构（80 - 90%），并呈现出一系列代表实际体内情况的孔微尺寸。体外蛋白水解生物降解表明，Smart Matrix(®)在体内植入后比Integra(®)降解更快。对于两种支架，酶消化均通过整体降解发生。这些观察到的差异可能会影响两种支架上的细胞行为。我们的结果表明，对支架的粘弹性、物理和生物可降解特性进行微调可以在细胞附着、增殖和浸润方面最大限度地发挥细胞行为，而这些对于组织修复至关重要。
