Gel scaffolds show promise for growing skin cells to treat severe burns

<p>Wound healing is a complex and dynamic process involving the interplay of various cellular and molecular mechanisms aimed at restoring skin integrity and function. Burns, a common type of acute wound, represent a significant challenge due to their high morbidity. Effective burn wound management requires advanced therapeutic strategies that create a favorable environment for healing through wound care, the use of advanced wound dressings, and surgical interventions including skin transplantation. There has been growing interest in novel approaches, such as biomaterials and cell-based therapies, which offer promising solutions for improving wound healing outcomes. This thesis explores innovative treatments designed to enhance wound healing, focusing on creating an optimal wound environment through assisted debridement and the use of biomaterials for dressings, dermal substitutes, and scaffolds for autologous cells.</p><p>In paper I, the potential of porous gelatin microcarriers (PGM) as a scaffold for delivering autologous keratinocytes and fibroblasts to wounds was investigated. In vitro experiments demonstrated that PGM supports cell attachment and proliferation, with an optimal transplantation time identified within 24 to 96 hours. Using a porcine model, wounds treated with cell-seeded PGM exhibited improved re-epithelialization compared to single-cell suspensions and untreated controls. Histological analysis revealed that the PGM were degraded within four weeks and supported the formation of a mature neo-epidermis, demonstrating its potential as an efficient and time-saving alternative to traditional cultured epidermal autografts.</p><p>The study presented in paper II assessed the efficacy of amino acid-buffered hypochlorite (AABH) as a debridement agent in an infected porcine burn model. AABH, in combination with mechanical debridement, was compared to mechanical debridement alone and untreated controls. AABH significantly improved the removal of necrotic tissue, reduced bacterial load, and promoted wound healing. These findings suggest that AABH could serve as an effective and accessible tool for wound debridement, particularly in settings where specialized surgical expertise is limited.</p><p>In paper III, a randomized clinical trial compared a bacterial cellulose (BC) dressing to a porcine xenograft (PX) dressing for treating partial-thickness burns. Wounds treated with the BC dressing demonstrated healing times comparable to those of the PX dressing. Additionally, there were no significant differences in infection rates, pain, impact on everyday life, length of hospital stay, dressing costs, need for surgical interventions, or scar assessment when comparing the two dressings. In conclusion, BC demonstrated equivalent effectiveness to PX, making it an alternative for burn wound management. Furthermore, a significant advantage of BC is that it is not animal-derived, addressing ethical and cultural concerns.</p><p>The study presented in paper IV explored the use of recombinant spider silk modified with bioactive fibronectin motifs (FN-silk) as a dermal substitute. Using a porcine full-thickness wound model, FN-silk was compared to the collagen-based matrix MatriDerm®. FN-silk demonstrated excellent biocompatibility, and the material was gradually degraded in vivo. Wounds treated with FN-silk displayed significantly enhanced re-epithelialization and higher elasticity compared to those treated with MatriDerm® or untreated controls. These results highlight FN-silk's potential as a next-generation biomaterial for promoting epidermal healing and dermal regeneration.</p>