Poly(hydroxybutyrate‐co‐hydroxyvalerate) Bilayer Skin Tissue Engineering Constructs with Improved Epidermal Rearrangement

Abstract

Bilayer skin substitutes constitute an attractive strategy towards improved skin wound healing. Therefore, solvent casting and freeze-drying methodologies are used to produce polyhydroxybutyrate-co-hydroxyvalerate (PHBV) thin nanoporous membranes and 3D porous scaffolds that are combined in bilayer structures to recreate the epidermal and dermal layers, respectively. The combination of these methodologies allow attaining a bilayer structure with a high water retention capability and adequate mechanical properties, susceptible to enzymes degradative action. Cultures established with human keratinocytes (hKC) and dermal fibroblasts (hDFb) confirm the suitability of the PHBV structures to support cell adhesion and proliferation. Nonetheless, when co-cultured under defined conditions, hKC are able to grow and rearrange in a multilayer structure with proliferative cells in the basal layer, and cells expressing a terminal differentiation marker in the upper layer. Therefore, PHBV bilayer structures demonstrate properties that favor skin cells performance, thus representing a promising strategy to improve wound healing.

Effect of different solvent systems on PHBV/PEO electrospun fibers

“…1 Due to the large surface area-to-volume ratio, high porosity and good exibility, electrospun nanobers have great potential in a number of applications such as tissue engineering, 2 ltration systems, 3 biosensors, 4 drug delivery 5 and wound healing. 6 The basic process of electrospinning is that, under a high electrostatic force, a uid jet would eject from the apex of the so-called "Taylor cone" of the charged polymer solution or melt when the electrostatic forces overcome the surface tension, and then the bers can be collected aer going through solvent evaporation. 7,8 The morphology and diameter of the electrospun bers depend on many parameters, including operating parameters, solution properties and ambient conditions.…”

Polyhydroxybutyrate-co-hydroxyvalerate structures loaded with adipose stem cells promote skin healing with reduced scarring

“…This can be Our group has recently developed a PHBV scaffold with a poros-97 ity of 82.2% ± 0.5% and an average pore size of 122.4 lm ± 58.1 lm 98 that possesses high water retention capability to maintain wound's 99 moisture[28]. This PHBV scaffold is susceptible to the degradative100 action of inflammatory enzymes thus supporting new tissue for-101 mation while the biomaterial is being degraded.…”

“…Trying to 36 overcome these issues, this work proposes the combination of poly(3-hydroxybutyrate-co-hydroxyvaler- 37 ate) (PHBV) structures with adipose-derived stem cells (ASCs) to offer biomechanical and biochemical 38 signaling cues necessary to improve wound healing in a full-thickness model. PHBV scaffold maintained 39 the wound moisture and demonstrated enough mechanical properties to withstand wound contraction.…”

“…Twenty-four 118 males, wild-type from the inbred lineage LEWIS/H were used as 119 recipient animals. All experimental protocols were performed in 120 accordance with the Ethical Principles of Animal Experimentation 121 and approved by the Animal Committee of Federal University of 122 Minas Gerais (CEUA/UFMG, protocol 168/2013).PHBV scaffolds were prepared as described previously[28].Briefly, the PHBV polymer (Mw 425.7 KDa, 12% HV content) pro-126 vided by PHB Industrial, Serrana, Brazil was dissolved in chloro-127 form (Fisher Scientific, UK) at 60°C under constant agitation to 128 form a homogeneous 2.5% w/v polymer solution. A 3D porous scaf-…”

Using Artificial Skin Devices as Skin Replacements: Insights into Superficial Treatment

“…Porous networks can be formed in these films to mimic the structure of skin, and also increase the elasticity of the polymer film . In another work, Correlo and co‐workers developed a bilayer skin tissue engineering construct from polyhydroxybutyrate‐ co ‐hydroxyvalerate (PHBV) for the improvement of epidermal rearrangement . A thin nanoporous epidermal layer was prepared via solvent casting, while a layer of larger pores was obtained by freeze‐drying for the dermal layer.…”