Three-Dimensional Skin Tissue Printing with Human Skin Cell Lines and Mouse Skin-Derived Epidermal and Dermal Cells

Abstract

Since the skin covers most surfaces of the body, it is susceptible to damage, which can be fatal depending on the degree of injury to the skin because it defends against external attack and protects internal structures. Various types of artificial skin are being studied for transplantation to repair damaged skin, and recently, the production of replaceable skin using three-dimensional (3D) bioprinting technology has also been investigated. In this study, skin tissue was produced using a 3D bioprinter with human skin cell lines and cells extracted from mouse skin, and the printing conditions were optimized. Gelatin was used as a bioink, and fibrinogen and alginate were used for tissue hardening after printing. Printed skin tissue maintained a survival rate of 90% or more when cultured for 14 days. Culture conditions were established using 8 mM calcium chloride treatment and the skin tissue was exposed to air to optimize epidermal cell differentiation. The skin tissue was cultured for 14 days after differentiation induction by this optimized culture method, and immunofluorescent staining was performed using epidermal cell differentiation markers to investigate whether the epidermal cells had differentiated. After differentiation, loricrin, which is normally found in terminally differentiated epidermal cells, was observed in the cells at the tip of the epidermal layer, and cytokeratin 14 was expressed in the lower cells of the epidermis layer. Collectively, this study may provide optimized conditions for bioprinting and keratinization for three-dimensional skin production.

Progress in the Application of 3D Skin Models for Cosmetic Assessment

“…3D bioprinting materials were first fabricated in 2009 [70], and the appreciable advantage of preoperative planning of complex operations involving the use of computed tomography or magnetic resonance imaging data has shown the potential to revolutionize cosmetic testing. Due to computer-driven bioprinting, cells and biomaterials can be deposited precisely and consistently [3,71,72]. The technology is still in the developing stage, and a skin equivalent that contains all skin elements has not yet been printed.…”

Moving lab-grown tissues into the clinic: organ-on-a-chip and bioengineered skin systems

“…To promote neovascularization, Yanez et al constructed a skin substitute that contained keratinocytes, fibroblasts, and HUVECs seeded in a collagen type I and fibrinogen matrix (Yanez et al, 2015). These were transplanted onto thymus-free nude mice and exhibited the formation of new microvessels and accelerated wound healing in comparison to a commercially available wound dressing (Apligraf) with the goal of creating customized skin surrogates, Jin et al used a gelatin bioink with fibrinogen and alginate to harden the tissue post-printing and the cultured tissue maintained a survival rate of 90% after 14 days (Jin et al, 2022). The authors focused on calcium ions due to their role in keratinization.…”

Local Drug Delivery Strategies towards Wound Healing

“…Therefore, to prevent the separation of the layers during application, a regenerative skin scaffold should take biomimetic mechanical cues into account. By adjusting the physicomechanical characteristics of each layer, the scaffold can offer tailored microenvironments for various cell types [ 155 ]. The use of autologous epidermal sheets as a kind of skin replacement has progressed into the use of more sophisticated bilayered cutaneous tissue-designed skin substitutes.…”