Poly(hydroxybutyrate-co-hydroxyvalerate) bilayer skin tissue engineering constructs with improved epidermal rearrangement

"Article first published online: 4 MAR 2014 (epub ahead of print)"Bilayer skin substitutes constitute an attractive strategy towards improved skinwound healing.Therefore, solvent casting and freeze-drying methodologies are used to produce polyhydroxybutyrate-co-hydroxyvalerate (PHBV) thin nanoporousmembranes and 3D porous scaffolds thatare combined in bilayer structures to recreate the epidermal and dermal layers, respectively. Thecombination of these methodologies allow attaining a bilayer structure with a high waterretention capability and adequate mechanical properties, susceptible to enzymes degradativeaction. Cultures established with human keratinocytes (hKC) and dermal fibroblasts(hDFb) confirm the suitability of the PHBV structures tosupport cell adhesion and proliferation. Nonetheless,when co-cultured under defined conditions, hKC are ableto grow and rearrange in a multilayer structure withproliferative cells in the basal layer, and cells expressing aterminal differentiation marker in the upper layer.Therefore, PHBV bilayer structures demonstrate propertiesthat favor skin cells performance, thus representing apromising strategy to improve wound healing.A.Z. acknowledges the Brazilian National Council for Scientific and Technological Development (CNPq) for a PhD Grant (141775/2010-6/141787/2012) and financial support of the projects 564779/2010-5 and 490414/2010-9, also the Brazilian Coordination of Improvement of Higher Education Personnel (CAPES) for providing the PhD scholarship abroad: PDEE0046/11-6. This work was also financed by the project RL1 - ABMR - NORTE-01-0124-FEDER-000016 co-financed by North Portugal Regional Operational Programme (ON.2 - O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF). Authors would also like to acknowledge Lucilia Goreti Ribeiro Pinto for the help with confocal images and Edith Ariza Avila for the help with SEM images