Traditionally, surgeons have used autologous (patient’s own) skin grafts for treating large skin injuries such as burns or complex nonhealing wounds. Despite their extensive application, autologous skin grafts are limited due to their dependence on the availability of a graft donor site, as well as the likelihood of resulting in scarring at the donor and recipient site. To address this, skin auto-micrografts can be harvested and techniques have been developed to expand the tissue. Furthermore, biodegradable scaffolds have been used for more than 50 years to provide a framework into which host cells can migrate. Integra®, a dermal replacement bilayer comprised of collagen and a glycosaminoglycan hydrogel, has been used in the treatment of burns and chronic wounds, with studies showing that use of the scaffold in chronic diabetic foot ulcers results in acceleration of wound closure as well as an improvement in the quality of healing. Given this background, we combined the two clinically effective techniques-autologous micrografts and scaffold application-to successfully treat diabetic wounds. Our results are promising for the development of a new therapeutic modality for wound repair.
Background: Therapeutic strategies that successfully combine autologous micrografting and biodegradable scaffolds offer great potential for improved wound repair. In this study we evaluate the efficacy of a novel modification of a collagen-glycosaminoglycan scaffold (CGS) with autologous micrografts using a murine dorsal wound model.
Methods: db/db mice underwent a full thickness 1.0cm2 dorsal wound excision and were treated with a CGS, a modified CGS (CGS+MG) or simple occlusive dressing (Blank). The modified scaffold was created by harvesting full thickness micrografts and transplanting these into the CGS membrane. Parameters of wound healing, including cellular proliferation, collagen deposition, keratinocyte migration, and angiogenesis were assessed.
Results: The group treated with the micrograft-modified scaffold healed at a faster rate, showed greater cellular proliferation (63.2±27.3µm vs. 624.4±284.3µm, p<0.0001), collagen deposition (18.7±2.9 vs. 34.5±5.2%; p<0.0001), with higher density (28.2±9.8 vs. 12.2±5.2 vessels/HPF; p=0.001) and greater maturity (61.8 ± 7.6% vs. 20.1 ± 8.4%; p<0.0001) of microvessels. The grafts remained viable within the scaffold.
Conclusion: We report successful treatment of diabetic wounds with a novel scaffold modified with full-thickness automicrografts. Clinically, the successful scaffold engraftment, micrograft viability and improved wound healing offer promising results for the development of a new therapeutic modality for wound repair.