Advances in bioprinted cell-laden hydrogels for skin tissue engineering

Abstract

Bioprinting technologies are powerful additive biofabrication techniques to produce cellular constructs for skin tissue engineering owing to their unique ability to precisely pattern living and non-living materials in predefined spatial locations. This unique feature, combined with the computer controlled printing and medical imaging techniques, enable researchers and clinicians to generate patient specific constructs partly replicating the intricate compositional and architectural organization of the skin. Bioprinting has been used to automatically dispense hydrogels with skin cells located in prescribed sites that promote skin formation in vitro and in vivo. Current skin bioprinting approaches mostly rely on the sequential printing of fibroblasts and keratinocytes embedded within a homogeneous hydrogel. Although such approaches have already been translated to pre-clinical scenarios, they still present limitations in terms of fully replicating the cellular and extracellular matrix (ECM) heterogeneity in native skin. The success of bioprinting for skin repair strongly depends on the design of printable bioinks capable of supporting the function of printed cells and stimulating the production of new ECM components. To better mimic the human skin, novel developments in dedicated bioprinting technologies, in the design of bioinks, as well as in the printing of vascularised constructs are necessary. This paper presents an overview regarding the use of bioprinting for skin tissue engineering applications. The operating principles of bioprinting technologies are outlined along with requirements of printed skin constructs. Finally, preclinical results are summarized and future perspectives for the field are highlighted.

Polysaccharide-Based Bioink Formulation for 3D Bioprinting of an In Vitro Model of the Human Dermis

“…Among its various vital functions, the human skin possesses highly effective self-regenerative properties, which is related to the presence of epidermal stem cells in different skin layers [1,4]. After damage, the skin activates its natural ability to promote spontaneous repair by following a four-stage process: hemostasis, inflammation, proliferation, and remodeling [4,5].…”

Regenerative Wound Dressings for Skin Cancer

“…Generally, the skin plays four fundamental roles, namely body protection against physical, chemical, and bacteriological damages, thermoregulation through skin vasculature and eccrine sweat glands, prevention of dehydration, and conduction of neurosensory information which further contributes to endocrine function and immune surveillance regulations [ 21 , 22 ]. Hence, maintaining its integrity is fundamental.…”

3D-Printed Poly(ɛ-caprolactone)/Graphene Scaffolds Activated with P1-Latex Protein for Bone Regeneration

“…[7][8][9] The first approach is based on the use of biodegradable and biocompatible porous scaffolds that are implanted into the lesion site without cells, seeded with autologous or allogeneic cells and then implanted, or seeded with cells and then cultured in vitro to produce tissue-engineered constructs prior implantation. [6][7][8][9][10] In this approach, scaffolds, from either natural or synthetic materials, provide the appropriated biomechanical environment to allow cells to produce their own extracellular matrix. In the second approach, specific additive manufacturing techniques (e.g., extrusion-based processes, laser bioprinting, or material jetting processes) are used to print cells immobilized within polymeric hydrogels producing cell-laden three-dimensional (3D) constructs.…”