bims-biprem Biomed News
on Bioprinting for regenerative medicine
Issue of 2023–08–13
nine papers selected by
Seerat Maqsood, University of Teramo



  1. Cureus. 2023 Jul;15(7): e41624
      The shortage of organs for transplantation is a global crisis, with an increasing demand and an inadequate supply of organ donors. The convergence of biology and engineering has led to the emergence of 3D bioprinting, which enables the precise and customizable construction of biological structures. Various 3D bioprinting techniques include inkjet printing, extrusion printing, and laser-assisted bioprinting (LAB). Although it has the potential for many benefits, 3D bioprinting comes with its own set of challenges and requirements, specifically associated with the bioprinting of various tissues. The challenges of bioprinting include issues with cells, bioinks, and bioprinters, as well as ethical concerns, clinical efficacy, and cost-effectiveness, making it difficult to integrate 3D bioprinting into widespread clinical practice. Three-dimensional bioprinting holds great promise in addressing the organ shortage crisis, and its applications extend beyond organ transplantation to include drug screening, disease modeling, and regenerative medicine. However, further research is needed to overcome the technical, biological, and ethical challenges associated with 3D bioprinting, paving the way for its widespread clinical implementation. This article discusses the processes and challenges of bioprinting as well as the current research direction in the field.
    Keywords:  3d-bioprinting; bio engineering; bioinks; regenerative medicine treatments; tissue engineering & regenerative medicine
    DOI:  https://doi.org/10.7759/cureus.41624
  2. Cureus. 2023 Aug;15(8): e43204
      This article provides a comprehensive review of the current trends and challenges in the development of 3D-printed heart valves and other cardiac implants. By providing personalized solutions and pushing the limits of regenerative medicine, 3D printing technology has revolutionized the field of cardiac healthcare. The use of several organic and synthetic polymers in 3D printing heart valves is explored in this article, with emphasis on both their benefits and drawbacks. In cardiac tissue engineering, stem cells are essential, and their potential to lessen immunological rejection and thrombogenic consequences is highlighted. In the clinical applications section, the article emphasizes the importance of 3D printing in preoperative planning. Surgery results are enhanced when surgeons can visualize and assess the size and placement of implants using patient-specific anatomical models. Customized implants that are designed to match the anatomy of a particular patient reduce the likelihood of complications and enhance postoperative results. The development of physiologically active cardiac implants, made possible by 3D bioprinting, shows promise by eliminating the need for artificial valves. In conclusion, this paper highlights cutting-edge research and the promise of 3D-printed cardiac implants to improve patient outcomes and revolutionize cardiac treatment.
    Keywords:  3d printing; bioprinting; cardiac; implant; review; surgery; valve
    DOI:  https://doi.org/10.7759/cureus.43204
  3. Adv Mater. 2023 Aug 11. e2304738
      Bioprinting has attracted much attention due to its suitability for fabricating biomedical devices. In particular, bioprinting has become one of the growing centres in the field of wound healing, with various types of bioprinted devices being developed, including 3D scaffolds, microneedle patches and flexible electronics. Bioprinted devices can be designed with specific biostructures and biofunctions that closely match the shape of wound sites and accelerate the regeneration of skin through various approaches. Herein, a comprehensive review of the bioprinting of smart wound dressings (SWDs) is presented, emphasizing the crucial effect of bioprinting in determining biostructures and biofunctions. The review begins with an overview of bioprinting techniques and bioprinted devices, followed with an in-depth discussion of polymer-based inks, modification strategies, additive ingredients, properties and applications. The strategies for the modification of bioprinted devices are divided into 7 categories, including chemical synthesis of novel inks, physical blending, coaxial bioprinting, multi-material bioprinting, physical absorption, chemical immobilization, and hybridization with living cells, and examples are presented. Thereafter, the frontiers of bioprinting and wound healing, including 4D bioprinting, artificial intelligence (AI)-assisted bioprinting, and in situ bioprinting, are discussed from a perspective of interdisciplinary sciences. Finally, the current challenges and future prospects in this field are highlighted. This article is protected by copyright. All rights reserved.
    Keywords:  3D scaffolds; bioprinting; flexible electronics; microneedle patches; wound healing
    DOI:  https://doi.org/10.1002/adma.202304738
  4. Brain Tumor Res Treat. 2023 Jul;11(3): 159-165
      The three-dimensional (3D) printing itself is not a novel technology, it is more than 30 years old. Stereolithographic (SLA) technology has been used as the first and popular technology for medical application of 3D printing. Since 1991 Radiology and Plastic Surgery have published articles about SLA for rapid prototyping anatomical 3D models. Medical applications of 3D printing have been popularizing and stabilizing so far. Implantable medical devices such as metal or absorbable implants, surgical guide systems, prosthesis and orthosis, and 3D anatomical models for normal or diseased anatomy have been developing and expanding its markets so far. There are many obstacles, such as insurance, authorization as a medical device, and lack of standards technology for further expansion of medical applications. Many technical specifications and guidelines for authorization as medical device have been published by regulatory bodies from many countries. Even though international standards for 3D printing have been developing more and more, there have been few standards for medical application of 3D printing. In this harsh environment academia, company, research institute, regulatory bodies, and government have been doing good job for the development of 3D printing industry.
    Keywords:  3D model; 3D printing; Guide; Implant; Internationa; Standard
    DOI:  https://doi.org/10.14791/btrt.2023.0001
  5. Mater Today Bio. 2023 Aug;21 100726
      3D printing as a powerful technology enables the fabrication of organ structures with a programmed geometry, but it is usually difficult to produce large-size tissues due to the limited working space of the 3D printer and the instability of bath or ink materials during long printing sessions. Moreover, most printing only allows preparation with a single ink, while a real organ generally consists of multiple materials. Inspired by the 3D puzzle toy, we developed a "building block-based printing" strategy, through which the preparation of 3D tissues can be realized by assembling 3D-printed "small and simple" bio-blocks into "large and complex" bioproducts. The structures that are difficult to print by conventional 3D printing such as a picture puzzle consisting of different materials and colors, a collagen "soccer" with a hollow yet closed structure, and even a full-size human heart model are successfully prepared. The 3D puzzle-inspired preparation strategy also allows for a reasonable combination of various cells in a specified order, facilitating investigation into the interaction between different kinds of cells. This strategy opens an alternative path for preparing organ structures with multiple materials, large size and complex geometry for tissue engineering applications.
    Keywords:  3D printing; 3D puzzle-inspired assembly; Biomaterials; Full-size organ construction; Tissue engineering
    DOI:  https://doi.org/10.1016/j.mtbio.2023.100726
  6. Sci Rep. 2023 08 07. 13(1): 12829
      Hydrogels are used extensively as cell-culture scaffolds for both 2D and 3D cell cultures due to their biocompatibility and the ease in which their mechanical and biological properties can be tailored to mimic natural tissue. The challenge when working with hydrogel-based scaffolds is in their handling, as hydrogels that mimic e.g. brain tissue, are both fragile and brittle when prepared as thin (sub-mm) membranes. Here, we describe a method for facile handling of thin hydrogel cell culture scaffolds by molding them onto a polycaprolactone (PCL) mesh support attached to a commonly used Transwell set-up in which the original membrane has been removed. In addition to demonstrating the assembly of this set-up, we also show some applications for this type of biological membrane. A polyethylene glycol (PEG)-gelatin hydrogel supports cell adhesion, and the structures can be used for biological barrier models comprising either one or multiple hydrogel layers. Here, we demonstrate the formation of a tight layer of an epithelial cell model comprising MDCK cells cultured over 9 days by following the build-up of the transepithelial electrical resistances. Second, by integrating a pure PEG hydrogel into the PCL mesh, significant swelling is induced, which leads to the formation of a non-adherent biological scaffold with a large curvature that is useful for spheroid formation. In conclusion, we demonstrate the development of a handling platform for hydrogel cell culture scaffolds for easy integration with conventional measurement techniques and miniaturized organs-on-chip systems.
    DOI:  https://doi.org/10.1038/s41598-023-39081-x
  7. Sci Bull (Beijing). 2023 Jul 31. pii: S2095-9273(23)00501-7. [Epub ahead of print]
      
    DOI:  https://doi.org/10.1016/j.scib.2023.07.045
  8. Front Bioeng Biotechnol. 2023 ;11 1214431
      In recent years, significant biotechnological advancements have been made in engineering human cardiac tissues and organ-like models. This field of research is crucial for both basic and translational research due to cardiovascular disease being the leading cause of death in the developed world. Additionally, drug-associated cardiotoxicity poses a major challenge for drug development in the pharmaceutical and biotechnological industries. Progress in three-dimensional cell culture and microfluidic devices has enabled the generation of human cardiac models that faithfully recapitulate key aspects of human physiology. In this review, we will discuss 3D pluripotent stem cell (PSC)-models of the human heart, such as engineered heart tissues and organoids, and their applications in disease modeling and drug screening.
    Keywords:  cardiac; cardiotoxicity; drug; engineered heart tissues; human pluripotent stem cells; organoid
    DOI:  https://doi.org/10.3389/fbioe.2023.1214431
  9. Br Dent J. 2023 Aug 09.
      Aims To develop an optimal clinical and laboratory protocol for the fabrication of 3D printing dentures.Design A prospective feasibility study across three UK dental schools.Material and methods Each patient received one conventional and one 3D-printed denture. Both dentures were constructed using the same impression, jaw registration and wax trial denture. Variables investigated included methods of digitisation of the impression and optional use of a 3D-printed baseplate for jaw registration.Results Clinicians strongly preferred 3D-printed baseplates. Patients felt that conventional and printed dentures were similar in retention and stability. More patients favoured conventional dentures over 3D-printed dentures in terms of comfort.Discussion It is feasible to combine conventional clinical work with digital techniques to produce 3D-printed dentures. 3D-printed baseplates offer a cost-effective alternative to conventional bases at the jaw registration stage. Challenges were faced in tooth positioning and managing occlusion, particularly where roots required adjustment.Conclusion 3D printing is suitable for producing baseplates for jaw registration blocks and wax trial insertions. It is feasible to produce 3D-printed dentures using conventional clinical techniques for impressions, jaw registration and wax trial insertion. The workflow used in this study for 3D-printed dentures is not superior to conventional dentures. Further work is required.
    DOI:  https://doi.org/10.1038/s41415-023-6114-0