Sulfated hyaluronan‐containing artificial extracellular matrices promote proliferation of keratinocytes and melanotic phenotype of melanocytes from the outer root sheath of hair follicles

Sulfated hyaluronic acid/collagen-based biomimetic hybrid nanofiber skin for diabetic wound healing: Development and preliminary evaluation

Diabetic foot ulcers (DFUs) are one of the most serious and devastating complication of diabetes, manifesting as foot ulcers and impaired wound healing in patients with diabetes mellitus. To solve this problem, sulfated hyaluronic acid (SHA)/collagen-based nanofibrous biomimetic skins was developed and used to promote the diabetic wound healing and skin remodeling. First, SHA was successfully synthetized using chemical sulfation and incorporated into collagen (COL) matrix for preparing the SHA/COL hybrid nanofiber skins. The polyurethane (PU) was added into those hybrid scaffolds to make up the insufficient mechanical properties of SHA/COL nanofibers, the morphology, surface properties and degradation rate of hybrid nanofibers, as well as cell responses upon the nanofibrous scaffolds were studied to evaluate their potential for skin reconstruction. The results demonstrated that the SHA/COL, SHA/HA/COL hybrid nanofiber skins were stimulatory of cell behaviors, including a high proliferation rate and maintaining normal phenotypes of specific cells. Notably, SHA/COL and SHA/HA/COL hybrid nanofibers exhibited a significantly accelerated wound healing and a high skin remodeling effect in diabetic mice compared with the control group. Overall, SHA/COL-based hybrid scaffolds are promising candidates as biomimetic hybrid nanofiber skin for accelerating diabetic wound healing.

Laccase-Treated Polystyrene Surfaces with Caffeic Acid, Dopamine, and L-3,4-Dihydroxyphenylalanine Substrates Facilitate the Proliferation of Melanocytes and Embryonal Carcinoma Cells NTERA-2

This study presents the effects of treating polystyrene (PS) cell culture plastic with oxidoreductase enzyme laccase and the catechol substrates caffeic acid (CA), L-DOPA, and dopamine on the culturing of normal human epidermal melanocytes (NHEMs) and human embryonal carcinoma cells (NTERA-2). The laccase-substrate treatment improved PS hydrophilicity and roughness, increasing NHEM and NTERA-2 adherence, proliferation, and NHEM melanogenesis to a level comparable with conventional plasma treatment. Cell adherence dynamics and proliferation were evaluated. The NHEM endpoint function was quantified by measuring melanin content. PS surfaces treated with laccase and its substrates demonstrated the forming of polymer-like structures. The surface texture roughness gradient and the peak curvature were higher on PS treated with a combination of laccase and substrates than laccase alone. The number of adherent NHEM and NTERA-2 was significantly higher than on the untreated surface. The proliferation of NHEM and NTERA-2 correspondingly increased on treated surfaces. NHEM melanin content was enhanced 6-10-fold on treated surfaces. In summary, laccase- and laccase-substrate-modified PS possess improved PS surface chemistry/hydrophilicity and altered roughness compared to untreated and plasma-treated surfaces, facilitating cellular adherence, subsequent proliferation, and exertion of the melanotic phenotype. The presented technology is easy to apply and creates a promising custom-made, substrate-based, cell-type-specific platform for both 2D and 3D cell culture.

Collagen/glycosaminoglycan-based matrices for controlling skin cell responses

Wound healing and tissue regeneration are orchestrated by the cellular microenvironment, e.g. the extracellular matrix (ECM). Including ECM components in biomaterials is a promising approach for improving regenerative processes, e.g. wound healing in skin. This review addresses recent findings for enhanced epidermal-dermal regenerative processes on collagen (coll)/glycosaminoglycan (GAG)-based matrices containing sulfated GAG (sGAG) in simple and complex in vitro models. These matrices comprise 2D-coatings, electrospun nanofibrous scaffolds, and photo-crosslinked acrylated hyaluronan (HA-AC)/coll-based hydrogels. They demonstrated to regulate keratinocyte and fibroblast migration and growth, to stimulate melanogenesis in melanocytes from the outer root sheath (ORS) of hair follicles and to enhance the epithelial differentiation of human mesenchymal stem cells (hMSC). The matrices' suitability for delivery of relevant growth factors, like heparin-binding epidermal growth factor like growth factor (HB-EGF), further highlights their potential as bioinspired, functional microenvironments for enhancing skin regeneration.