logo
    A new biodegradable matrix as part of a cell seeded skin substitute for the treatment of deep skin defects: A physico-chemical characterisation
    39
    Citation
    22
    Reference
    10
    Related Paper
    Citation Trend
    Keywords:
    Artificial skin
    Skin equivalent
    Human skin
    Matrix (chemical analysis)
    Human skin equivalents (HSEs) are tissue engineered constructs that model epidermal and dermal components of human skin. These models have been used to study skin development, wound healing, and grafting techniques. Many HSEs continue to lack vasculature and are additionally analyzed through post-culture histological sectioning which limits volumetric assessment of the structure. Presented here is a straightforward protocol utilizing accessible materials to generate vascularized human skin equivalents (VHSE); further described are volumetric imaging and quantification techniques of these constructs. Briefly, VHSEs are constructed in 12 well culture inserts in which dermal and epidermal cells are seeded into rat tail collagen type I gel. The dermal compartment is made up of fibroblast and endothelial cells dispersed throughout collagen gel. The epidermal compartment is made up of keratinocytes (skin epithelial cells) that differentiate at the air-liquid interface. Importantly, these methods are customizable based on needs of the researcher, with results demonstrating VHSE generation with two different fibroblast cell types: human dermal fibroblasts (hDF) and human lung fibroblasts (IMR90s). VHSEs were developed, imaged through confocal microscopy, and volumetrically analyzed using computational software at 4- and 8-week timepoints. An optimized process to fix, stain, image, and clear VHSEs for volumetric examination is described. This comprehensive model, imaging, and analysis techniques are readily customizable to the specific research needs of individual labs with or without prior HSE experience.
    Human skin
    Skin equivalent
    Compartment (ship)
    Stain
    Artificial skin
    Cell type
    Citations (3)
    Three-dimensional (3D) bioprinting, a flexible automated on-demand platform for the free-form fabrication of complex living architectures, is a novel approach for the design and engineering of human organs and tissues. Here, we demonstrate the potential of 3D bioprinting for tissue engineering using human skin as a prototypical example. Keratinocytes and fibroblasts were used as constituent cells to represent the epidermis and dermis, and collagen was used to represent the dermal matrix of the skin. Preliminary studies were conducted to optimize printing parameters for maximum cell viability as well as for the optimization of cell densities in the epidermis and dermis to mimic physiologically relevant attributes of human skin. Printed 3D constructs were cultured in submerged media conditions followed by exposure of the epidermal layer to the air-liquid interface to promote maturation and stratification. Histology and immunofluorescence characterization demonstrated that 3D printed skin tissue was morphologically and biologically representative of in vivo human skin tissue. In comparison with traditional methods for skin engineering, 3D bioprinting offers several advantages in terms of shape- and form retention, flexibility, reproducibility, and high culture throughput. It has a broad range of applications in transdermal and topical formulation discovery, dermal toxicity studies, and in designing autologous grafts for wound healing. The proof-of-concept studies presented here can be further extended for enhancing the complexity of the skin model via the incorporation of secondary and adnexal structures or the inclusion of diseased cells to serve as a model for studying the pathophysiology of skin diseases.
    3D bioprinting
    Human skin
    Citations (673)
    Abstract : Skin Equivalents (SE) or Human Skin Equivalents (HSEs) are skin substitutes that can serve as models for testing the skin permeability of agents from formulations, or for evaluation of formulations themselves on the skin. We have developed a collagen based HSE and HSE containing electrospun poly(DTE carbonate) polymer scaffolds in our laboratory. The culture of these full thickness skin equivalents has been optimized by modification of the culture media and conditions required for growth in order to mimic the barrier properties of human skin in vivo. The HSE has been characterized for morphology, lipid composition and barrier properties and compared to a commercially available skin equivalent, and shows similar permeability to a wide range of agents. Skin derived cells were found to populate and proliferate in the electrospun scaffold, which imparts structural stability to the collagen based HSE model. Use of cocultures of human dermal fibroblasts and human keratinocytes, and conditions such as addition of ascorbic acid are being used to look at effects on morphogenesis and barrier properties of the epidermal layer in these HSE models. Once developed, these skin equivalents can serve as effective models for determination of the permeation of chemical warfare agents (CWAs) or their mimics or the barrier properties of creams such as SERPACWA (Skin Exposure Reduction Paste Against Chemical Warfare Agents).
    Skin equivalent
    Human skin
    Equivalent
    Artificial skin
    Citations (0)
    As a major extracellular matrix component within the skin, collagen has been widely used to engineer human skin tissues. However, most collagen is extracted from animals. Here, we introduced recombinant human type III collagen (rhCol3) as a bioactive component to formulate bioinks for the bioprinting of a full-thickness human skin equivalent. Human dermal fibroblasts were encapsulated in the gelatin methacryloyl-rhCol3 composite bioinks and printed on a transwell to form the dermis layer, on which human epidermal keratinocytes were seeded to perform an air-liquid interface culture for 6 weeks. After optimizing the bioink formulation and bioprinting process, we investigated the effect of rhCol3 on skin tissue formation. The results suggest that a higher concentration of rhCol3 would enhance the growth of both cells, resulting in a more confluent (~100%) spreading of the epidermal keratinocytes at an early stage (3 days), compared to the rhCol3-free counterpart. Moreover, in an in vivo experiment, adding rhCol3 in the hydrogel formulation would contribute to the skin wound healing process. Taken together, we conclude that rhCol3 could act as a functional bioink component to promote basic skin cellular processes for skin tissue engineering.
    Skin equivalent
    Human skin
    Gelatin
    Artificial skin
    3D bioprinting
    Citations (43)
    Human skin equivalents (HSEs) are tissue engineered constructs that model epidermal and dermal components of human skin. These models have been used to study skin development, wound healing, and grafting techniques. Many HSEs continue to lack vasculature and are additionally analyzed through post-culture histological sectioning which limits volumetric assessment of the structure. Presented here is a straightforward protocol utilizing accessible materials to generate vascularized human skin equivalents (VHSE); further described are volumetric imaging and quantification techniques of these constructs. Briefly, VHSEs are constructed in 12 well culture inserts in which dermal and epidermal cells are seeded into rat tail collagen type I gel. The dermal compartment is made up of fibroblast and endothelial cells dispersed throughout collagen gel. The epidermal compartment is made up of keratinocytes (skin epithelial cells) that differentiate at the air-liquid interface. Importantly, these methods are customizable based on needs of the researcher, with results demonstrating VHSE generation with two different fibroblast cell types: human dermal fibroblasts (hDF) and human lung fibroblasts (IMR90s). VHSEs were developed, imaged through confocal microscopy, and volumetrically analyzed using computational software at 4- and 8-week timepoints. An optimized process to fix, stain, image, and clear VHSEs for volumetric examination is described. This comprehensive model, imaging, and analysis techniques are readily customizable to the specific research needs of individual labs with or without prior HSE experience.
    Human skin
    Skin equivalent
    Stain
    Compartment (ship)
    Artificial skin
    Cell type
    Citations (8)
    Human skin
    Epidermis (zoology)
    Skin equivalent
    Skin repair
    Artificial skin
    Ex vivo
    Dermal fibroblast