BiofabricationPub Date : 2024-11-19DOI: 10.1088/1758-5090/ad867d
John A Rector Iv, Lucas McBride, Callie M Weber, Kira Grossman, Alexander Sorets, Lissa Ventura-Antunes, Isabella Holtz, Katherine Young, Matthew Schrag, Ethan S Lippmann, Leon M Bellan
{"title":"Fabrication of endothelialized capillary-like microchannel networks using sacrificial thermoresponsive microfibers.","authors":"John A Rector Iv, Lucas McBride, Callie M Weber, Kira Grossman, Alexander Sorets, Lissa Ventura-Antunes, Isabella Holtz, Katherine Young, Matthew Schrag, Ethan S Lippmann, Leon M Bellan","doi":"10.1088/1758-5090/ad867d","DOIUrl":"10.1088/1758-5090/ad867d","url":null,"abstract":"<p><p>In the body, capillary beds fulfill the metabolic needs of cells by acting as the sites of diffusive transport for vital gasses and nutrients. In artificial tissues, replicating the scale and complexity of capillaries has proved challenging, especially in a three-dimensional context. In order to better develop thick artificial tissues, it will be necessary to recreate both the form and function of capillaries. Here we demonstrate a top-down method of patterning hydrogels using sacrificial templates formed from thermoresponsive microfibers whose size and architecture approach those of natural capillaries. Within the resulting microchannels, we cultured endothelial monolayers that remain viable for over three weeks and exhibited functional barrier properties. Additionally, we cultured endothelialized microchannels within hydrogels containing fibroblasts and characterized the viability of the co-cultures to demonstrate this approach's potential when applied to cell-laden hydrogels. This method represents a step forward in the evolution of artificial tissues and a path towards producing viable capillary-scale microvasculature for engineered organs.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11575475/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142457141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BiofabricationPub Date : 2024-11-15DOI: 10.1088/1758-5090/ad8fd5
Leanne M Friedrich, Ross T Gunther
{"title":"Simulated inter-filament fusion in embedded 3D printing.","authors":"Leanne M Friedrich, Ross T Gunther","doi":"10.1088/1758-5090/ad8fd5","DOIUrl":"10.1088/1758-5090/ad8fd5","url":null,"abstract":"<p><p>In embedded 3D printing (EMB3D), a nozzle extrudes continuous filaments inside of a viscoelastic support bath. Compared to other extrusion processes, EMB3D enables softer structures and print paths that conform better to the shape of the part, allowing for complex structures such as tissues and organs. However, strategies for high-quality dimensional accuracy and mechanical properties remain undocumented in EMB3D. This work uses computational fluid dynamics simulations in OpenFOAM to probe the underlying physics behind two processes: deformation of the printed part due to nearby nozzle motion and fusion between neighboring filaments during printing. Through simulations, we disentangle yielding from viscous dissipation, and we isolate interfacial tension effects from rheology effects, which are difficult to separate in experiments. Critically, these simulations find that disturbance and fusion are controlled by the flow of support fluid around the nozzle. To avoid part deformation, the nozzle must remain far from existing parts during non-printing moves, moreso when traveling next to the part than above the part and especially when the interfacial tension between the ink and support is non-zero. Additionally, because support can become trapped between filaments at zero interfacial tension, the spacing between filaments must be tight enough to produce over-printing, or printing too much material for the designed space. In non-Newtonian fluids, spacings for vertical walls must be even tighter than spacings for horizontal planes. At these spacings, printing a new filament sometimes creates and sometimes mitigates shape defects in the old filament. While non-zero ink-support interfacial tensions produce better inter-filament fusion than zero interfacial tension, interfacial tension also produces shape defects. Slicing algorithms that consider these unique EMB3D defects are needed to improve mechanical properties and dimensional accuracy of bioprinted constructs.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BiofabricationPub Date : 2024-11-13DOI: 10.1088/1758-5090/ad8ca6
Sarah Pragnere, Lucie Essayan, Naima El-Kholti, Emma Petiot, Cyril Pailler-Mattei
{"title":"<i>In vitro</i>bioprinted 3D model enhancing osteoblast-to-osteocyte differentiation.","authors":"Sarah Pragnere, Lucie Essayan, Naima El-Kholti, Emma Petiot, Cyril Pailler-Mattei","doi":"10.1088/1758-5090/ad8ca6","DOIUrl":"https://doi.org/10.1088/1758-5090/ad8ca6","url":null,"abstract":"<p><p><i>In vitro</i>bone models are pivotal for understanding tissue behavior and cellular responses, particularly in unravelling certain pathologies' mechanisms and assessing the impact of new therapeutic interventions. A desirable<i>in vitro</i>bone model should incorporate primary human cells within a 3D environment that mimics the mechanical properties characteristics of osteoid and faithfully replicate all stages of osteogenic differentiation from osteoblasts to osteocytes. However, to date, no bio-printed model using primary osteoblasts has demonstrated the expression of osteocytic protein markers. This study aimed to develop bio-printed<i>in vitro</i>model that accurately captures the differentiation process of human primary osteoblasts into osteocytes. Given the considerable impact of hydrogel stiffness and relaxation behavior on osteoblast activity, we employed three distinct cross-linking solutions to fabricate hydrogels. These hydrogels were designed to exhibit either similar elastic behavior with different elastic moduli, or similar elastic moduli with varying relaxation behavior. These hydrogels, composed of gelatin (5% w/v), alginate (1%w/v) and fibrinogen (2%w/v), were designed to be compatible with micro-extrusion bioprinting and proliferative. The modulation of their biomechanical properties, including stiffness and viscoelastic behavior, was achieved by applying various concentrations of cross-linkers targeting both gelatin covalent bonding (transglutaminase) and alginate chains' ionic cross-linking (calcium). Among the conditions tested, the hydrogel with a low elastic modulus of 8 kPa and a viscoelastic behavior over time exhibited promising outcomes regarding osteoblast-to-osteocyte differentiation. The cessation of cell proliferation coincided with a significant increase in alkaline phosphatase activity, the development of dendrites, and the expression of the osteocyte marker PHEX. Within this hydrogel, cells actively influenced their environment, as evidenced by hydrogel contraction and the secretion of collagen I. This bio-printed model, demonstrating primary human osteoblasts expressing an osteocyte-specific protein, marks a significant achievement. We envision its substantial utility in advancing research on bone pathologies, including osteoporosis and bone tumors.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":"17 1","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142614291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BiofabricationPub Date : 2024-11-12DOI: 10.1088/1758-5090/ad8bf4
Sushobhan Sarker, Mario Köster, Omkar Desai, Muhammad Imran Rahim, Sabrina Herrmann, Sara Behme, Meike Stiesch, Hansjörg Hauser, Dagmar Wirth
{"title":"A generic cell-based biosensor converts bacterial infection signals into chemoattractants for immune cells.","authors":"Sushobhan Sarker, Mario Köster, Omkar Desai, Muhammad Imran Rahim, Sabrina Herrmann, Sara Behme, Meike Stiesch, Hansjörg Hauser, Dagmar Wirth","doi":"10.1088/1758-5090/ad8bf4","DOIUrl":"10.1088/1758-5090/ad8bf4","url":null,"abstract":"<p><p>Bacterial infection is a major challenge to human health. Although various potent antibiotics have emerged in recent decades, current challenges arise from the increasing number of multi-drug-resistant species. Infections associated with implants represent a particular challenge because they are usually diagnosed at an advanced stage and are difficult to treat with antibiotics owing to the formation of protective biofilms. In this study, we designed and explored a synthetic biology-inspired cell-based biosensor/actor for the detection and counteraction of bacterial infections. The system is generic, as it senses diverse types of infections and acts by enhancing the endogenous immune system. This strategy is based on genetically engineered sensor/actor cells that can sense type I interferons (IFNs), which are released by immune cells at the early stages of infection. IFN signalling activates a synthetic circuit to induce reporter genes with a sensitivity of only 5 pg ml<sup>-1</sup>of IFN and leads to a therapeutic protein output of 100 ng ml<sup>-1</sup>, resulting in theranostic cells that can visualize and fight infections. Robustness and resilience were achieved by implementing a positive feedback loop. We showed that diverse gram-positive and gram-negative implant-associated pathogenic bacteria activate the cascade in co-culture systems in a dose-dependent manner. Finally, we showed that this system can be used to secrete chemoattractants that facilitate the infiltration of immune cells in response to bacterial triggers. Together, the system is not only universal to bacterial infections, but also hypersensitive, allowing the sensing of infections at initial stages.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BiofabricationPub Date : 2024-11-11DOI: 10.1088/1758-5090/ad89fe
Md Sarker, Soomin Park, Vivek Kumar, Chang H Lee
{"title":"Micro-thin hydrogel coating integrated in 3D printing for spatiotemporal delivery of bioactive small molecules.","authors":"Md Sarker, Soomin Park, Vivek Kumar, Chang H Lee","doi":"10.1088/1758-5090/ad89fe","DOIUrl":"10.1088/1758-5090/ad89fe","url":null,"abstract":"<p><p>Three-dimensional (3D) printing incorporated with controlled delivery is an effective tool for complex tissue regeneration. Here, we explored a new strategy for spatiotemporal delivery of bioactive cues by establishing a precise-controlled micro-thin coating of hydrogel carriers on 3D-printed scaffolds. We optimized the printing parameters for three hydrogel carriers, fibrin cross-linked with genipin, methacrylate hyaluronic acid, and multidomain peptides, resulting in homogenous micro-coating on desired locations in 3D printed polycaprolactone microfibers at each layer. Using the optimized multi-head printing technique, we successfully established spatial-controlled micro-thin coating of hydrogel layers containing profibrogenic small molecules (SMs), Oxotremorine M and PPBP maleate, and a chondrogenic cue, Kartogenin. The delivered SMs showed sustained releases up to 28 d and guided regional differentiation of mesenchymal stem cells, thus leading to fibrous and cartilaginous tissue matrix formation at designated scaffold regions<i>in vitro</i>and<i>in vivo</i>. Our micro-coating of hydrogel carriers may serve as an efficient approach to achieve spatiotemporal delivery of various bioactive cues through 3D printed scaffolds for engineering complex tissues.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11552100/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BiofabricationPub Date : 2024-11-11DOI: 10.1088/1758-5090/ad8b71
Wei Chen, Ke Gai, Xiao Luo, Bing Wu, Xiu Wang, Wei Shi, Kai Zhang, Feng Lin, Wei Sun, Yu Song
{"title":"3D bioprinted<i>in vitro</i>epilepsy models for pharmacological evaluation in temporal lobe epilepsy.","authors":"Wei Chen, Ke Gai, Xiao Luo, Bing Wu, Xiu Wang, Wei Shi, Kai Zhang, Feng Lin, Wei Sun, Yu Song","doi":"10.1088/1758-5090/ad8b71","DOIUrl":"10.1088/1758-5090/ad8b71","url":null,"abstract":"<p><p>This study introduces a novel<i>in vitro</i>model for intractable temporal lobe epilepsy (TLE) utilizing 3D bioprinting technology, aiming to replicate the complex neurobiological characteristics of TLE more accurately. Primary neural cell constructs were fabricated and subjected to epileptiform-inducing conditions, fostering synaptic proliferation and neuronal loss. Systematically electrophysiological and immunofluorescent analyses indicated that significant synaptic connectivity and sustained epileptiform activities within the constructs akin to those observed in human epilepsy models. Notably, the model responded to treatments with phenytoin and tetrodotoxin, illustrating its potential utility in drug response kinetics studies. Furthermore, we performed drug permeability simulations using COMSOL Multiphysics to analyze the diffusion characteristics of these drugs within the constructs. These results confirm that our 3D bioprinted neural model provides a physiologically relevant and ethically sustainable platform, which is beneficial for studying TLE mechanisms and developing therapeutic strategies with high accuracy and clinical relevance.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A photocurable and thermocurable composite hydrogel and the application in a contraction resistant full-thickness skin model.","authors":"Xiaoran Li, Chunyan Wang, Qianwei Xiong, Ningbei Yin, Jing Zhang, Jie Zhang, Keyu Yang, Zhuoyue Xu, Jianjun Ge, Lifeng Sha, Xiaoyue Wu, Yun Zhou, Zaozao Chen, Zhongze Gu","doi":"10.1088/1758-5090/ad905e","DOIUrl":"https://doi.org/10.1088/1758-5090/ad905e","url":null,"abstract":"<p><p>Three-dimensional (3D) organotypic skin in vitro has attracted increasing attention for drug development, cosmetics evaluation, and even clinical applications. However, the severe contraction of these models restricts their application, especially in the analyses based on barrier functions such as percutaneous penetration. For the full-thickness skin equivalents, the mechanical properties of the dermis scaffold plays an important role in the contraction resistance. In this investigation, we optimized a hydrogel composed of gelatine methacrylamide (GelMA), hyaluronic acid methacrylate (HAMA), and type I collagen (Col I), adjusted the elastic moduli to 2.27±0.08 kPa to fit the skin cells growth and resist contraction as well. This optimized hydrogel exhibited a swelling ratio of 23.25 ± 0.94% and demonstrated satisfactory cell viability in fibroblasts cultures. Then, we mixed this hydrogel with fibroblasts of liquid-liquid culture to construct the dermis, on which seeded keratinocytes were seeded for another 14 days of air-liquid culture to form cornified epidermis, and a commercialized hydrogel Ava-FT-Skin was used as control. This optimized skin model could maintained its integrity for a prolonged period of 28 days. Differentiated epidermis presented basal, spinous, granular, and cornified layers, meanwhile, epidermis markers like keratin-10, keratin-14, involucrin, loricrin, filaggrin, and dermis markers vimentin were expressed distinctly in the right distribution. Furthermore, penetration of a 607 Da Cascade blue-labelled dextran was calculated and compared to the Avatarget skin model, both of which could prevent more than 99% of the fluorescent molecule. We consider that this full-thickness skin model could be widely used in pharmaceutical and cosmetic industries, especially in penetration detection, contributing to the excellent contraction resistance.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A versatile natural gelatin-based hydrogel for emergency wound treatment through hemostasis, antibacterial, and anti-inflammation.","authors":"Xiaoling Cao, Yonghao Deng, Zhongye Xu, Tingting Wang, Bing Tang, Jiande Han, Rui Guo, Rong Yin","doi":"10.1088/1758-5090/ad89ff","DOIUrl":"10.1088/1758-5090/ad89ff","url":null,"abstract":"<p><p>Emergency wounds are often accompanied by bacterial infection, oxidative stress, and excessive inflammation due to the inability to quickly close and stop bleeding, resulting in chronic wounds that are difficult to heal. Clinically, surgical suturing is the fastest method for wound closure, but it is only suitable for wounds with small bleeding volumes and causes unsightly scar formation. Consequently, there is a critical need for hemostatic dressings versatile enough to address a spectrum of diverse and intricate wounds, especially in emergency scenarios. In this study, we constructed a unique versatile natural gelatin-based hydrogel with hemostasis, antibacterial, and anti-inflammation properties. The hydrogel was composed of 4-(4-(hydroxymethyl)-2-methoxy-5-nitrophenoxy) butyrylethylenediamine-modified methacrylated gelatin (GelMA-NB) and epigallocatechin gallate-grafted polylysine (EPL-EGCG), which imparts adhesion, antibacterial and antioxidant properties to the hydrogel. Simultaneously, the hydrogel was loaded with GelMA microspheres encapsulating natural resveratrol (RES@GM). This combination not only exhibited outstanding hemostatic capabilities but also preserved the anti-inflammatory potential of RES. In different animal models, the hydrogel exhibited outstanding hemostatic and wound healing effects, down-regulated the expression of IL-1<i>β</i>to promote inflammatory regulation and potential for angiogenesis and anti-scar. In conclusion, unique versatile natural gelatin-based hydrogel suitable for various complex wounds provides a promising strategy for emergency wound dressing applications.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improved visualisation of ACP-engineered osteoblastic spheroids: a comparative study of contrast-enhanced micro-CT and traditional imaging techniques.","authors":"Torben Hildebrand, Qianli Ma, Dagnija Loca, Kristaps Rubenis, Janis Locs, Liebert Parreiras Nogueira, Håvard Jostein Haugen","doi":"10.1088/1758-5090/ad8bf5","DOIUrl":"10.1088/1758-5090/ad8bf5","url":null,"abstract":"<p><p>This study investigates osteoblastic cell spheroid cultivation methods, exploring flat-bottom, U-bottom, and rotary flask techniques with and without amorphous calcium phosphate (ACP) supplementation to replicate the 3D bone tissue microenvironment. ACP particles derived from eggshell waste exhibit enhanced osteogenic activity in 3D models. However, representative imaging of intricate 3D tissue-engineered constructs poses challenges in conventional imaging techniques due to notable scattering and absorption effects in light microscopy, and hence limited penetration depth. We investigated contrast-enhanced micro-CT as a methodological approach for comprehensive morphological 3D-analysis of the<i>in-vitro</i>model and compared the technique with confocal laser scanning microscopy, scanning electron microscopy and classical histology. Phosphotungstic acid and iodine-based contrast agents were employed for micro-CT imaging in laboratory and synchrotron micro-CT imaging. Results revealed spheroid shape variations and structural integrity influenced by cultivation methods and ACP particles. The study underscores the advantage of 3D spheroid models over traditional 2D cultures in mimicking bone tissue architecture and cellular interactions, emphasising the growing demand for novel imaging techniques to visualise 3D tissue-engineered models. Contrast-enhanced micro-CT emerges as a promising non-invasive imaging method for tissue-engineered constructs containing ACP particles, offering insights into sample morphology, enabling virtual histology before further analysis.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BiofabricationPub Date : 2024-11-05DOI: 10.1088/1758-5090/ad88a6
Hamed Alizadeh Sardroud, Gustavo Dos Santos Rosa, William Dust, Tat-Chuan Cham, Gwen Roy, Sarah Bater, Alan Chicoine, Ali Honaramooz, Xiongbiao Chen, B Frank Eames
{"title":"Comparison study on hyaline cartilage versus fibrocartilage formation in a pig model by using 3D-bioprinted hydrogel and hybrid constructs.","authors":"Hamed Alizadeh Sardroud, Gustavo Dos Santos Rosa, William Dust, Tat-Chuan Cham, Gwen Roy, Sarah Bater, Alan Chicoine, Ali Honaramooz, Xiongbiao Chen, B Frank Eames","doi":"10.1088/1758-5090/ad88a6","DOIUrl":"10.1088/1758-5090/ad88a6","url":null,"abstract":"<p><p>Cartilage tissue engineering (CTE) with the help of engineered constructs has shown promise for the regeneration of hyaline cartilage, where fibrocartilage may also be formed due to the biomechanical loading resulting from the host weight and movement. Previous studies have primarily reported on hyaline cartilage formation<i>in vitro</i>and/or in small animals, while leaving the fibrocartilage formation undiscovered. In this paper, we, at the first time, present a comparison study on hyaline cartilage versus fibrocartilage formation in a large animal model of pig by using two constructs (namely hydrogel and hybrid ones) engineered by means of three-dimensional (3D) bioprinting. Both hydrogel and hybrid constructs were printed from the bioink of alginate (2.5%) and ATDC5 cells (chondrogenic cells at a cell density of 5 × 10<sup>6</sup>cells ml<sup>-1</sup>), with the difference in that in the hybrid construct, there was a polycaprolactone (PCL) strand printed between every two bioink strands, which were strategically designed to shield the force imposed on the cells within the bioink strands. Both hydrogel and hybrid constructs were implanted into the chondral defects created in the articular cartilage of weight-bearing portions of pig stifle joints; the cartilage formation was examined at one- and three-months post-implantation, respectively, by means of Safranin O, Trichrome, immunofluorescent staining, and synchrotron radiation-based (SR) inline phase contrast imaging microcomputed tomography (inline-PCI-CT). Glycosaminoglycan (GAG) and collagen type II (Col II) secretion were used to evaluate the hyaline cartilage formation, while collagen type I (Col I) was used to indicate fibrocartilage given that Col I is low in hyaline cartilage but high in fibrocartilage. Our results revealed that cartilage formation was enhanced over time in both hydrogel and hybrid constructs; particularly, the hydrogel construct exhibited more cartilage formation at both one- and three-months post-implantation, while hybrid constructs tended to have less fibrocartilage formed in a long time period. Also, the result from the inline-PCI-CT revealed that the inline-PCI-CT was able to provide not only the information seen in other histology images, but also high-resolution details of biomaterials and regenerating cartilage. This would represent a significant advance toward the non-invasive assessment of cartilage formation regeneration within large animal models and eventually in human patients.</p>","PeriodicalId":8964,"journal":{"name":"Biofabrication","volume":" ","pages":""},"PeriodicalIF":8.2,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142457139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}