In vitro and in vivo assessment of lactic acid‐modified chitosan scaffolds for potential treatment of full‐thickness burns

Autologous skin transplantation is today's “gold standard” treatment for full‐thickness burns. However, when > 30% of total body surface area is damaged, there is an important shortage of autologous donor sites for skin grafting; then, treatment alternatives become crucial. Such alternatives can be based on polymeric scaffolds capable of functioning as protective covers and cells/factors carriers. Chitosan (CTS) is a natural‐derived polymer with relevant biological‐related properties but poor mechanical performance. Improved mechanical properties can be achieved through lactic acid grafting (LA‐g); nevertheless, LA‐g affects the biological response towards the CTS‐based materials. In this work, CTS‐LA scaffolds with different LA‐g percentages were synthesized and evaluated to determine appropriate LA‐g degrees for full‐thickness burns treatment. In vitro results indicated that the higher the LA‐g percentage, the lower the capability of the scaffolds to sustain fibroblasts culture. Scaffolds with LA‐g around 28% (CTS‐LA28) sustained cell culture and allowed normal cell functionality. Further evaluation of CTS‐LA28 as acellular and cellular grafts in a full‐thickness burn mouse model showed that at 28 days post‐burn, macroscopic characteristic of the reparation tissue were closer to healthy skin when cellular grafts were used for treatment; histological evaluation also showed that dermis cellularity and collagenous fibers structure were similar to those in healthy skin when cellular grafts were used for burns treatment. © 2017 Wiley Periodicals Inc. J Biomed Mater Res Part A: 105A: 2875–2891, 2017.