Biological Cover Mitigates Disruption of the Dermal Structure in Mechanically Expanded Skin in a Porcine Model

Tissue expansion is an integral procedure of the vast majority of breast reconstruction and has a significant impact on the final clinical outcomes. Therefore, technological advances leading to a fewer number of unfavorable outcomes and a decrease in complication rates are imperative. In this study, using a porcine model, we investigated an effect of acellular dermal matrix (ADM) used as a tissue expander cover on the dermal changes induced by mechanical forces during tissue expansion. After 14 days of expansion, skin samples were collected from one animal, while the second animal underwent radiation, and tissue was collected 8 weeks later. Tissue expanded without the use of ADM and unexpanded skin served as the controls. Collected skin biopsies were used for histological and immunohistochemical evaluation, and for gene expression analysis. We revealed that the biological cover incorporation into host tissue is facilitated by macrophages without inducing a broad inflammatory response. The utilization of ADM mitigated disruption in the dermal structure, excessive collagen deposition, and capsule formation in non-irradiated expanded skin. The protective effect was not fully maintained in irradiated skin. These results demonstrate that tissue expansion might be improved by using the tissue expander cover.