A human skin equivalent burn model to study the effect of a nanocrystalline silver dressing on wound healing

Previously, we have shown that extracellular basic pH plays a significant role in both the direct and indirect regulation of cellular processes in a wound; this in turn affects the wound-healing process. Several studies have demonstrated the importance of apoptosis modulation in the wound-healing process, especially in removing inflammatory cells and in inhibiting scar formation. However, the effects of extracellular basic pH on wound healing-related skin damage are yet to be examined. Therefore, we investigated the induction of accelerated apoptosis by extracellular basic pH in skin. Apoptosis-related protein levels were measured using an array kit, target protein expression levels were detected by immunostaining, lactate dehydrogenase was analyzed spectrophotometrically, and Annexin V levels were measured by fluorescence staining. Basic pH (8.40) strongly upregulated extrinsic apoptosis proteins (Fas, high temperature requirement A, and p21) and slightly upregulated intrinsic apoptosis proteins (cytochrome c, B-cell lymphoma 2 [Bcl-2], Bcl-2-associated death promoter, and Bcl-2-like protein 4) in a 3D human skin equivalent system. Moreover, basic pH (8.40) induced heat shock protein (HSP) 60 and 70. In addition, basic pH-exposed Fas- and HSP60-knockdown cells showed significantly decreased levels of apoptosis. Taken together, these results indicate that extracellular basic pH increases early-stage apoptosis through Fas/FasL via modulation of HSP60 and HSP70.

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Demonstration of re-epithelialization in a bioprinted human skin equivalent wound model

10.1101/2020.06.15.152140 ◽

2020 ◽

Author(s):

Carlos Poblete Jara ◽

Carolina Motter Catarino ◽

Yuguo Lei ◽

Lício Augusto Velloso ◽

Pankaj Karande ◽

...

Keyword(s):

Wound Healing ◽

Human Skin ◽

Wound Closure ◽

Skin Wound ◽

Skin Equivalent ◽

Surrounding Tissue ◽

Skin Wound Healing ◽

Over The Top ◽

Human Skin Equivalent

AbstractObjectiveThe development of an in vitro platform for modeling human skin injury and the re-epithelization process.ApproachA fibrin provisional matrix (FPM) was installed into a wound facsimile of a bioprinted human skin equivalent (HSE). A mixture of plasma-derived fibrinogen-containing factor XIII, fibronectin, thrombin, and macrophages (an FPM “bioink”) was extruded into the wound site. The surrounding in vitro tissue culture became a source of keratinocytes to achieve wound closure by a re-epithelialization process signaled by the FPM.ResultsAn in vitro analog of wound closure and re-epithelialization by keratinocytes occurred over the FPM after a normal migration initiation at 3 days.InnovationA physiologic mixture of macrophage/fibrinogen/fibronectin that supports macrophage differentiation was applied to a mechanically wounded, bioprinted dermal tissue. We developed a transitional culture medium to mimic the changing microenvironment during the initial phases of wound healing. As a reference, we temporally compared our in vitro model with a murine skin wound healing.ConclusionThis co-culture model was shown to temporally synchronize a re-epithelization process for initiation of keratinocyte migration from a surrounding tissue and the migration process over the top of an FPM. A future study of the analogous subepithelial healing pathway is envisioned using the same in vitro bioprinted tissue study platform for co-culture of keratinocytes, melanocytes, fibroblasts, endothelial cells, and macrophages using more specialized FPMs.

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Desmosomal distribution in the epidermis of a non-contracting human skin equivalent

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124884 ◽

1992 ◽

Vol 50 (1) ◽

pp. 896-897

Author(s):

L.X. Oakford ◽

S.D. Dimitrijevich ◽

R. Gracy

Keyword(s):

Human Skin ◽

Basal Layer ◽

Skin Equivalent ◽

Tissue Component ◽

Intact Skin ◽

Similar Sequence ◽

Sequence Of Events ◽

Suprabasal Keratinocytes ◽

Human Skin Equivalent

In intact skin the epidermal layer is a dynamic tissue component which is maintained by a basal layer of mitotically active cells. The protective upper epidermis, the stratum corneum, is generated by differentiation of the suprabasal keratinocytes which eventually desquamate as anuclear comeocytes. A similar sequence of events is observed in vitro in the non-contracting human skin equivalent (HSE) which was developed in this lab (1). As a part of the definition process for this model of living skin we are examining its ultrastructural features. Since desmosomes are important in maintaining cell-cell interactions in stratified epithelia their distribution in HSE was examined.

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Transformative Encounters and Uncanny Intimacies: Biotechnology and Contemporary Art – A Practitioner's Approach and Perspective

Somatechnics ◽

10.3366/soma.2012.0061 ◽

2012 ◽

Vol 2 (2) ◽

pp. 263-283 ◽

Cited By ~ 1

Author(s):

Svenja J. Kratz

Keyword(s):

Tissue Culture ◽

Human Skin ◽

Contemporary Art ◽

Skin Equivalent ◽

Biomedical Innovation ◽

Equivalent Models ◽

Science Projects ◽

Insight Into ◽

Human Skin Equivalent

Abstract: Presented from an ArtScience practitioner's perspective, this paper provides an overview of Svenja Kratz's experience working as an artist within the area of cell and tissue culture at QUT's Institute of Health and Biomedical Innovation (IHBI). Using The Absence of Alice, a multi-medium exhibition based on the experience of culturing cells, as a case study, the paper gives insight into the artist's approach to working across art and science and how ideas, processes, and languages from each discipline can intermesh and extend the possibilities of each system. The paper also provides an overview of her most recent artwork, The Human Skin Equivalent/Experience Project, which involves the creation of personal jewellery items incorporating human skin equivalent models grown from the artist's skin and participant cells. Referencing this project, and other contemporary bioart works, the value of ArtScience is discussed, focusing in particular on the way in which cross-art-science projects enable an alternative voice to enter into scientific dialogues and have the potential to yield outcomes valuable to both disciplines.

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