Self-propagating Autologous Skin Substrate for the Treatment of Cutaneous Defects: Clinical Series of the Utilization of a Novel Therapy for In Vivo Full-thickness Skin Regeneration.

INTRODUCTION: The rate of incidence of full-thickness chronic and acute dermal wounds is increasing and becoming a significant burden on healthcare systems. Large and complex wounds, which are unable to heal on their own, or reconstruction patient management strategies that have failed to fully close wounds are frequently treated by skin grafting, a procedure that is over 2-millennia old and is still being used as a conventional treatment option. Split-thickness skin grafts (STSGs) have not demonstrated neogeneration of dermal appendages (hair follicles, sweat and sebaceous glands, etc) or full-thickness skin replacement and consequently are prone to contraction, fibrosis, infection, and morbidity. Skin grafting requires surgeons and an operating room, which inherently produces a barrier to patients and the wound care community, including nonsurgical clinicians and midlevel providers. Here we investigate outcomes from a multi-institutional case series of early clinical use of a novel autologous homologous skin construct (AHSC) for complex wounds. A retrospective cohort study at 9 institutions between December 1, 2017, and July 23, 2018, of 15 patients (age range, 7–72 years) with wounds which had failed the clinical standard of care or complex wounds where modalities beyond skin grafting would have been required. METHODS: Biomedical manufacturing of a small full-thickness skin harvest into the AHSC cell-tissue product followed by application into a clean wound bed. Wound closure, AHSC % take, volume restoration, hair-follicle presence, 2-point discrimination, bioimpedance, pigment propagation, Raman spectroscopy, and histomorphologic assessment of regenerated skin were conducted on regenerated skin specimen when possible. RESULTS: The entire cohort of 15 patients had successful wound preparation and application of AHSC following full-thickness skin harvest. No repeat treatment with AHSC or STSG was required for AHSC-treated wounds. No donor site complications were reported. All patients had complete AHSC take and wound coverage at the time of follow-up (average, 4.0 ± 2.9 months). Two-point discrimination, bioimpedance, Raman spectroscopy, and histomorphologic analyses showed that AHSC-regenerated skin was analogous to native skin. Hair follicles were present in healed AHSC-treated wounds and were similar to native skin hair follicles on histomorphologic and Raman spectroscopy analysis. CONCLUSIONS: This novel treatment method demonstrated regeneration of full-thickness skin with minimal donor site morbidity and was able to cover exposed underlying structures in complex wounds. Due to the observed results, utilization of AHSC can be considered as a therapeutic option for patients suffering from burns, complex wound reconstruction, chronic wounds, and traumatic defects. Therapy utilizing AHSC can be performed by surgical and nonsurgical trained clinicians and midlevel providers across a variety of care settings, including resource-poor areas. AHSC demonstrated safe and efficacious treatment for the complete closure of complex cutaneous wounds refractory to conventional therapies and cases involving open deep structures not amenable to reconstruction with STSGs alone.