bims-biprem Biomed News
on Bioprinting for regenerative medicine
Issue of 2024‒06‒23
eleven papers selected by
Seerat Maqsood, University of Teramo



  1. J Clin Med. 2024 Jun 02. pii: 3278. [Epub ahead of print]13(11):
      Three-dimensional (3D) printing is dramatically improving breast reconstruction by offering customized and precise interventions at various stages of the surgical process. In preoperative planning, 3D imaging techniques, such as computer-aided design, allow the creation of detailed breast models for surgical simulation, optimizing surgical outcomes and reducing complications. During surgery, 3D printing makes it possible to customize implants and precisely shape autologous tissue flaps with customized molds and scaffolds. This not only improves the aesthetic appearance, but also conforms to the patient's natural anatomy. In addition, 3D printed scaffolds facilitate tissue engineering, potentially favoring the development and integration of autologous adipose tissue, thus avoiding implant-related complications. Postoperatively, 3D imaging allows an accurate assessment of breast volume and symmetry, which is crucial in assessing the success of reconstruction. The technology is also a key educational tool, enhancing surgeon training through realistic anatomical models and surgical simulations. As the field evolves, the integration of 3D printing with emerging technologies such as biodegradable materials and advanced imaging promises to further refine breast reconstruction techniques and outcomes. This study aims to explore the various applications of 3D printing in breast reconstruction, addressing current challenges and future opportunities.
    Keywords:  3D bioprinting; 3D imaging; 3D printing; biodegradable implants; breast mold; breast reconstruction; flap shaping; scaffolds; tissue engineering
    DOI:  https://doi.org/10.3390/jcm13113278
  2. ACS Omega. 2024 Jun 11. 9(23): 24219-24235
      In recent years, 3D bioprinting with various types of bioinks has been widely used in tissue engineering to fabricate human tissues and organs with appropriate biological functions. Decellularized extracellular matrix (dECM) is an excellent bioink candidate because it is enriched with a variety of bioactive proteins and bioactive factors and can provide a suitable environment for tissue repair or tissue regeneration while reducing the likelihood of severe immune rejection. In this Review, we systematically review recent advances in 3D bioprinting and decellularization technologies and comprehensively detail the latest research and applications of dECM as a bioink for tissue engineering in various systems, with the aim of providing a reference for researchers in tissue engineering to better understand the properties of dECM bioinks.
    DOI:  https://doi.org/10.1021/acsomega.4c02847
  3. ACS Appl Mater Interfaces. 2024 Jun 17.
      Three-dimensional (3D) printing, an additive manufacturing technique, is increasingly used in the field of tissue engineering. The ability to create complex structures with high precision makes the 3D printing of this material a preferred method for constructing personalized and functional materials. However, the challenge lies in developing affordable and accessible materials with the desired physiochemical and biological properties. In this study, we used eggshell microparticles (ESPs), an example of bioceramic and unconventional biomaterials, to reinforce thermoplastic poly(ε-caprolactone) (PCL) scaffolds via extrusion-based 3D printing. The goal was to conceive a sustainable, affordable, and unique personalized medicine approach. The scaffolds were fabricated with varying concentrations of eggshells, ranging from 0 to 50% (w/w) in the PCL scaffolds. To assess the physicochemical properties, we employed scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and X-ray diffraction analysis. Mechanical properties were evaluated through compression testing, and degradation kinetics were studied through accelerated degradation with the remaining mass ranging between 89.4 and 28.3%. In vitro, we evaluated the characteristics of the scaffolds using the MC3T3-E1 preosteoblasts over a 14 day period. In vitro characterization involved the use of the Alamar blue assay, confocal imaging, and real-time quantitative polymerase chain reaction. The results of this study demonstrate the potential of 3D printed biocomposite scaffolds, consisting of thermoplastic PCL reinforced with ESPs, as a promising alternative for bone-graft applications.
    Keywords:  3D printing; bone tissue engineering; eggshell particles; scaffolds; unconventional
    DOI:  https://doi.org/10.1021/acsami.4c02800
  4. Macromol Rapid Commun. 2024 Jun 17. e2400293
      Tissue repair and regeneration, such as bone and nerve repairs, encounter significant challenges due to limited regulations within the immune microenvironment, stem cells differentiation, and the key cell behavior. 3D scaffolds have been identified as a promising approach to address these issues via the efficiently structural regulations on cell fates and behaviors. In particular, 3D-printed polymer scaffolds with diverse micro/nanostructures offer a great potential for mimicking the structures of tissue, which can effectively modulate cell fates including cell phenotype, differentiation of stem cells, and migration and proliferation of key cells for promoting tissue repair and regeneration. Herein, the role of structural functions of 3D-printed polymer scaffolds in regulating the fates and behaviors of numerous cells related to tissue repair and regeneration, along with their specific influences are highlighted. Additionally, the challenges and outlooks associated with 3D-printed polymer scaffolds with various structures for modulating cell fates are also discussed. This article is protected by copyright. All rights reserved.
    Keywords:  3D printing; cell behavior; cell fate; polymer scaffolds; structural functions; tissue repair
    DOI:  https://doi.org/10.1002/marc.202400293
  5. Molecules. 2024 May 22. pii: 2443. [Epub ahead of print]29(11):
      Linear polyamides, known as nylons, are a class of synthetic polymers with a wide range of applications due to their outstanding properties, such as chemical and thermal resistance or mechanical strength. These polymers have been used in various fields: from common and domestic applications, such as socks and fishing nets, to industrial gears or water purification membranes. By their durability, flexibility and wear resistance, nylons are now being used in addictive manufacturing technology as a good material choice to produce sophisticated devices with precise and complex geometric shapes. Furthermore, the emergence of triboelectric nanogenerators and the development of biomaterials have highlighted the versatility and utility of these materials. Due to their ability to enhance triboelectric performance and the range of applications, nylons show a potential use as tribo-positive materials. Because of the easy control of their shape, they can be subsequently integrated into nanogenerators. The use of nylons has also extended into the field of biomaterials, where their biocompatibility, mechanical strength and versatility have paved the way for groundbreaking advances in medical devices as dental implants, catheters and non-absorbable surgical sutures. By means of 3D bioprinting, nylons have been used to develop scaffolds, joint implants and drug carriers with tailored properties for various biomedical applications. The present paper aims to collect evidence of these recently specific applications of nylons by reviewing the literature produced in recent decades, with a special focus on the newer technologies in the field of energy harvesting and biomedicine.
    Keywords:  3D printing; adhesive; biomedical; catheters; membranes; nylon; polyamide; sutures; triboelectric nanogenerators
    DOI:  https://doi.org/10.3390/molecules29112443
  6. Polymers (Basel). 2024 May 27. pii: 1511. [Epub ahead of print]16(11):
      A challenge in tissue engineering and the pharmaceutical sector is the development of controlled local release of drugs that raise issues when systemic administration is applied. Strontium is an example of an effective anti-osteoporotic agent, used in treating osteoporosis due to both anti-resorptive and anabolic mechanisms of action. Designing bone scaffolds with a higher capability of promoting bone regeneration is a topical research subject. In this study, we developed composite multi-layer three-dimensional (3D) scaffolds for bone tissue engineering based on nano-hydroxyapatite (HA), Sr-containing nano-hydroxyapatite (SrHA), and poly-ε-caprolactone (PCL) through the material extrusion fabrication technique. Previously obtained HA and SrHA with various Sr content were used for the composite material. The chemical, morphological, and biocompatibility properties of the 3D-printed scaffolds obtained using HA/SrHA and PCL were investigated. The 3D composite scaffolds showed good cytocompatibility and osteogenic potential, which is specifically recommended in applications when faster mineralization is needed, such as osteoporosis treatment.
    Keywords:  3D printing; bioactivity; co-precipitation; hydrothermal; hydroxyapatite nano-powder; poly-ε-caprolactone; strontium
    DOI:  https://doi.org/10.3390/polym16111511
  7. ACS Appl Bio Mater. 2024 Jun 21.
      Bone is remodeled through a dynamic process facilitated by biophysical cues that support cellular signaling. In healthy bone, signaling pathways are regulated by cells and the extracellular matrix and transmitted via electrical synapses. To this end, combining electrical stimulation (ES) with conductive scaffolding is a promising approach for repairing damaged bone tissue. Therefore, "smart" biomaterials that can provide multifunctionality and facilitate the transfer of electrical cues directly to cells have become increasingly more studied in bone tissue engineering. Herein, 3D-printed electrically conductive composite scaffolds consisting of demineralized bone matrix (DBM) and polycaprolactone (PCL), in combination with ES, for bone regeneration were evaluated for the first time. The conductive composite scaffolds were fabricated and characterized by evaluating mechanical, surface, and electrical properties. The DBM/PCL composites exhibited a higher compressive modulus (107.2 MPa) than that of pristine PCL (62.02 MPa), as well as improved surface properties (i.e., roughness). Scaffold electrical properties were also tuned, with sheet resistance values as low as 4.77 × 105 Ω/sq for our experimental coating of the highest dilution (i.e., 20%). Furthermore, the biocompatibility and osteogenic potential of the conductive composite scaffolds were tested using human mesenchymal stromal cells (hMSCs) both with and without exogenous ES (100 mV/mm for 5 min/day four times/week). In conjunction with ES, the osteogenic differentiation of hMSCs grown on conductive DBM/PCL composite scaffolds was significantly enhanced when compared to those cultured on PCL-only and nonconductive DBM/PCL control scaffolds, as determined through xylenol orange mineral staining and osteogenic protein analysis. Overall, these promising results suggest the potential of this approach for the development of biomimetic hybrid scaffolds for bone tissue engineering applications.
    Keywords:  3D printing; bone tissue engineering; conductive bone scaffolds; demineralized bone matrix; electrical stimulation; osteogenic differentiation
    DOI:  https://doi.org/10.1021/acsabm.4c00236
  8. Polymers (Basel). 2024 Jun 04. pii: 1592. [Epub ahead of print]16(11):
      Three-dimensional (3D) printing technology was able to generate great attention because of its unique methodology and for its major potential to manufacture detailed and customizable scaffolds in terms of size, shape and pore structure in fields like medicine, pharmaceutics and food. This study aims to fabricate an ink entirely composed of natural polymers, alginate, k-carrageenan and carboxymethyl cellulose (AkCMC). Extrusion-based 3D printing was used to obtain scaffolds based on a crosslinked interpenetrating polymer network from the alginate, k-carrageenan, carboxymethyl cellulose and glutaraldehide formulation using CaCl2, KCl and glutaraldehyde in various concentrations of acetic acid. The stabile bonding of the crosslinked scaffolds was assessed using infrared spectroscopy (FT-IR) as well as swelling, degradation and mechanical investigations. Moreover, morphology analysis (µCT and SEM) confirmed the 3D printed samples' porous structure. In the AkCMC-GA objects crosslinked with the biggest acetic acid concentration, the values of pores and walls are the highest, at 3.9 × 10-2 µm-1. Additionally, this research proves the encapsulation of vitamin B1 via FT-IR and UV-Vis spectroscopy. The highest encapsulation efficiency of vitamin B1 was registered for the AkCMC-GA samples crosslinked with the maximum acetic acid concentration. The kinetic release of the vitamin was evaluated by UV-Vis spectroscopy. Based on the results of these experiments, 3D printed constructs using AkCMC-GA ink could be used for soft tissue engineering applications and also for vitamin B1 encapsulation.
    Keywords:  drug delivery systems; polysaccharide scaffolds; vitamin B1
    DOI:  https://doi.org/10.3390/polym16111592
  9. J Mater Chem B. 2024 Jun 20.
      Three-dimensional bioprinting is a potent biofabrication technique in tissue engineering but is limited by inadequate bioink availability. Plant-derived proteins are increasingly recognized as highly promising yet underutilized materials for biomedical product development and hold potential for use in bioink formulations. Herein, we report the development of a biocompatible plant protein bioink from pea protein isolate. Through pH shifting, ethanol precipitation, and lyophilization, the pea protein isolate (PPI) transformed from an insoluble to a soluble form. Next, it was modified with glycidyl methacrylate to obtain methacrylate-modified PPI (PPIGMA), which is photocurable and was used as the precursor of bioink. The mechanical and microstructural studies of the hydrogel containing 16% PPIGMA revealed a suitable compress modulus and a porous network with a pore size over 100 μm, which can facilitate nutrient and waste transportation. The PPIGMA bioink exhibited good 3D bioprinting performance in creating complex patterns and good biocompatibility as plenty of viable cells were observed in the printed samples after 3 days of incubation in the cell culture medium. No immunogenicity of the PPIGMA bioink was identified as no inflammation was observed for 4 weeks after implantation in Sprague Dawley rats. Compared with methacrylate-modified gelatin, the PPIGMA bioink significantly enhanced cartilage regeneration in vitro and in vivo, suggesting that it can be used in tissue engineering applications. In summary, the PPIGMA bioink can be potentially used for tissue engineering applications.
    DOI:  https://doi.org/10.1039/d4tb00781f
  10. Bioprocess Biosyst Eng. 2024 Jun 13.
      Biosilica (BS) and spongin (SPG) from marine sponges are highlighted for their potential to promote bone regeneration. Moreover, 3D printing is introduced as a technology for producing bone grafts with optimized porous structures, allowing for better cell attachment, proliferation, and differentiation. Thus, this study aimed to characterize the BS and BS/SPG 3D printed scaffolds and to evaluate the biological effects in vitro. The scaffolds were printed using an ink containing 4 wt.% of sodium alginate. The physicochemical characteristics of BS and BS/SPG 3D printed scaffolds were analyzed by SEM, EDS, FTIR, porosity, evaluation of mass loss, and pH measurement. For in vitro analysis, the cellular viability of the MC3T3-E1 cell lineage was assessed using the AlamarBlue® assay and confocal microscopy, while genotoxicity and mineralization potential were evaluated through the micronucleus assay and Alizarin Red S, respectively. SEM analysis revealed spicules in BS, the fibrillar structure of SPG, and material degradation over the immersion period. FTIR indicated peaks corresponding to silicon oxide in BS samples and carbon oxide and amine in SPG samples. BS-SPG scaffolds exhibited higher porosity, while BS scaffolds displayed greater mass loss. pH measurements indicated a significant decrease induced by BS, which was mitigated by SPG over the experimental periods. In vitro studies demonstrated the biocompatibility and non-cytotoxicity of scaffold extracts. .Also, the scaffolds promoted cellular differentiation. The micronucleus test further confirmed the absence of genotoxicity. These findings suggest that 3D printed BS and BS/SPG scaffolds may possess desirable morphological and physicochemical properties, indicating in vitro biocompatibility.
    Keywords:  3D printing; Biosilica; Bone scaffolds; Marine sponges; Spongin
    DOI:  https://doi.org/10.1007/s00449-024-03042-z
  11. Int J Biol Macromol. 2024 Jun 14. pii: S0141-8130(24)03977-1. [Epub ahead of print] 133172
      In the field of bone tissue repair, the treatment of bone defects has always posed a significant challenge. In recent years, the advancement of bone tissue engineering and regenerative medicine has sparked great interest in the development of innovative bone grafting materials. In this study, a novel hydroxyapatite (HA) material was successfully prepared and comprehensively characterized. Antimicrobial experiments and biological evaluations were conducted to determine its efficacy. Based on the aforementioned research findings, 3D printing technology was employed to fabricate HA/chitosan (CS)/ polycaprolactone (PCL) scaffolds. The composition of the scaffold materials was confirmed through X-ray diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) tests, while the influence of different HA ratios on the scaffold surface morphology was observed. Additionally, antimicrobial experiments demonstrated the favorable antimicrobial activity of the scaffolds containing 30%HA + 5%CS + PCL. Furthermore, the water contact angle measurements confirmed the superhydrophilicity of the scaffolds. Finally, the excellent bioactivity and ability to promote tissue regeneration of the scaffolds were further confirmed by in vitro and in vivo experiments. This study provides new options for future repair and regeneration of bone tissue and clinical applications.
    Keywords:  Bone tissue repair; Chitosan; Hydroxyapatite
    DOI:  https://doi.org/10.1016/j.ijbiomac.2024.133172