In skin tissue engineering, a biodegradable scaffold is usually used where cells grow, produce its own cytokines, growth factors, and extracellular matrix, until the regenerated tissue gradually replaces the scaffold upon its degradation. However, the role of non-biodegradable scaffold remains unexplored. This study investigates the potential of a non-biodegradable bacterial nanocellulose/acrylic acid (BNC/AA) hydrogel to transfer human dermal fibroblasts (HDF) to the wound and the resulting healing effects of transferred HDF in athymic mice. Results demonstrated that the fabricated hydrogel successfully transferred >50% of HDF onto the wound site within 24 h, with evidence of HDF detected on day 7. The gene and protein study unveiled faster wound healing in the hydrogel with HDF group and characterized more mature newly formed skin microstructure on day 7, despite no visible differences. These findings give a new perspective regarding the role of non-biodegradable materials in skin tissue engineering, in the presence of exogenous cells, mainly at the molecular level.
Cell-based therapy has great potential to treat patients with lung diseases. The administration of cells into an injured lung is one method of repairing and replacing lost lung tissue. However, different types of delivery have been studied and compared, and none of the techniques resulted in engraftment of a high number of cells into the targeted organ. In this in vitro study, a novel method of cell delivery was introduced to investigate the possibility of delivering aerosolized skin-derived fibroblasts.
Split-skin grafting (SSG) is the gold standard treatment for full-thickness skin defects. For certain patients, however, an extensive skin lesion resulted in inadequacies of the donor site. Tissue engineering offers an alternative approach by using a very small portion of an individual's skin to harvest cells for propagation and biomaterials to support the cells for implantation. The objective of this study was to determine the effectiveness of autologous bilayered tissue-engineered skin (BTES) and single-layer tissue-engineered skin composed of only keratinocytes (SLTES-K) or fibroblasts (SLTES-F) as alternatives for full-thickness wound healing in a sheep model. Full-thickness skin biopsies were harvested from adult sheep. Isolated fibroblasts were cultured using medium Ham's F12: Dulbecco modified Eagle medium supplemented with 10% fetal bovine serum, whereas the keratinocytes were cultured using Define Keratinocytes Serum Free Medium. The BTES, SLTES-K, and SLTES-F were constructed using autologous fibrin as a biomaterial. Eight full-thickness wounds were created on the dorsum of the body of the sheep. On 4 wounds, polyvinyl chloride rings were used as chambers to prevent cell migration at the edge. The wounds were observed at days 7, 14, and 21. After 3 weeks of implantation, the sheep were euthanized and the skins were harvested. The excised tissues were fixed in formalin for histological examination via hematoxylin-eosin, Masson trichrome, and elastin van Gieson staining. The results showed that BTES, SLTES-K, and SLTES-F promote wound healing in nonchambered and chambered wounds, and BTES demonstrated the best healing potential. In conclusion, BTES proved to be an effective tissue-engineered construct that can promote the healing of full-thickness skin lesions. With the support of further clinical trials, this procedure could be an alternative to SSG for patients with partial- and full-thickness burns.