RESUMEN

Notable shortcomings exist in the currently available surgical options for reconstruction of bone and articular cartilage defects. Three-dimensional (3D) printing incorporating viable cells and extracellular matrix, or 3D bioprinting, is an additive manufacturing tissue engineering technique that can be used for layer-by-layer fabrication of highly complex tissues such as bone and cartilage. Because of the scalability of 3D bioprinting, this technology has the ability to fabricate tissues in clinically relevant volumes and addresses the defects of varying sizes and geometries. To date, most of our in vitro and in vivo success with cartilage and bone tissue bioprinting has been with extrusion-based bioprinting using alginate carriers and scaffold free bioinks. Fabrication of composite tissues has been achieved, including bone which includes vascularity, a necessary requisite to tissue viability. As this technology evolves, and we are able to integrate high-quality radiographic imaging, computer-assisted design, computer-assisted manufacturing, with real-time 3D bioprinting and ultimately in situ surgical printing, this additive manufacturing technique can be used to reconstruct both bone and articular cartilage and has the potential to succeed where our currently available clinical technologies and tissue manufacturing strategies fail.

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RESUMEN

BACKGROUND: Hernia repair is a common surgical procedure with polypropylene (PP) mesh being the standard material for correction because of its durability. However, complications such as seroma and pain are common, and repair failures still approach 15% secondary to poor tissue integration. In an effort to enhance mesh integration, we evaluated the applicability of a squid ring teeth (SRT) protein coating for soft-tissue repair in an abdominal wall defect model. SRT is a biologically derived high-strength protein with strong mechanical properties. We assessed tissue integration, strength, and biocompatibility of a SRT-coated PP mesh in a first-time pilot animal study. METHODS: PP mesh was coated with SRT (SRT-PP) and tested for mechanical strength against uncoated PP mesh. Cell proliferation and adhesion studies were performed in vitro using a 3T3 cell line. Rats underwent either PP (n = 3) or SRT-PP (n = 6) bridge mesh implantation in an anterior abdominal wall defect model. Repair was assessed clinically and radiographically, with integration evaluated by histology and mechanical testing at 60 days. RESULTS: Cell proliferation was enhanced on SRT-PP mesh. This was corroborated in vivo by abdominal wall histology, dramatically diminished craniocaudal mesh contraction, improved strength testing, and higher tissue failure strain. There was no increase in seroma or visceral adhesion formation. No foreign body reactions were noted on liver histology. CONCLUSIONS: SRT applied as a coating appears to augment mesh-tissue integration and improve abdominal wall stability following bridged repair. Further studies in larger animals will determine its applicability for hernia repair in patients.

RESUMEN

: Three-dimensional (3D) bioprinting is a revolutionary technology in building living tissues and organs with precise anatomic control and cellular composition. Despite the great progress in bioprinting research, there has yet to be any clinical translation due to current limitations in building human-scale constructs, which are vascularized and readily implantable. In this article, we review the current limitations and challenges in 3D bioprinting, including in situ techniques, which are one of several clinical translational models to facilitate the application of this technology from bench to bedside. A detailed discussion is made on the technical barriers in the fabrication of scalable constructs that are vascularized, autologous, functional, implantable, cost-effective, and ethically feasible. Clinical considerations for implantable bioprinted tissues are further expounded toward the correction of end-stage organ dysfunction and composite tissue deficits.

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