1
|
Eckstein KN, Hergert JE, Uzcategui AC, Schoonraad SA, Bryant SJ, McLeod RR, Ferguson VL. Controlled Mechanical Property Gradients Within a Digital Light Processing Printed Hydrogel-Composite Osteochondral Scaffold. Ann Biomed Eng 2024:10.1007/s10439-024-03516-x. [PMID: 38684606 DOI: 10.1007/s10439-024-03516-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 04/07/2024] [Indexed: 05/02/2024]
Abstract
Tissue engineered scaffolds are needed to support physiological loads and emulate the micrometer-scale strain gradients within tissues that guide cell mechanobiological responses. We designed and fabricated micro-truss structures to possess spatially varying geometry and controlled stiffness gradients. Using a custom projection microstereolithography (μSLA) system, using digital light projection (DLP), and photopolymerizable poly(ethylene glycol) diacrylate (PEGDA) hydrogel monomers, three designs with feature sizes < 200 μm were formed: (1) uniform structure with 1 MPa structural modulus ( E ) designed to match equilibrium modulus of healthy articular cartilage, (2) E = 1 MPa gradient structure designed to vary strain with depth, and (3) osteochondral bilayer with distinct cartilage ( E = 1 MPa) and bone ( E = 7 MPa) layers. Finite element models (FEM) guided design and predicted the local mechanical environment. Empty trusses and poly(ethylene glycol) norbornene hydrogel-infilled composite trusses were compressed during X-ray microscopy (XRM) imaging to evaluate regional stiffnesses. Our designs achieved target moduli for cartilage and bone while maintaining 68-81% porosity. Combined XRM imaging and compression of empty and hydrogel-infilled micro-truss structures revealed regional stiffnesses that were accurately predicted by FEM. In the infilling hydrogel, FEM demonstrated the stress-shielding effect of reinforcing structures while predicting strain distributions. Composite scaffolds made from stiff μSLA-printed polymers support physiological load levels and enable controlled mechanical property gradients which may improve in vivo outcomes for osteochondral defect tissue regeneration. Advanced 3D imaging and FE analysis provide insights into the local mechanical environment surrounding cells in composite scaffolds.
Collapse
Affiliation(s)
- Kevin N Eckstein
- Paul M. Rady Department of Mechanical Engineering, University of Colorado at Boulder, 427 UCB, Boulder, CO, 80309, USA
| | - John E Hergert
- Materials Science and Engineering Program, University of Colorado at Boulder, Boulder, CO, USA
| | - Asais Camila Uzcategui
- Materials Science and Engineering Program, University of Colorado at Boulder, Boulder, CO, USA
| | - Sarah A Schoonraad
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, CO, USA
| | - Stephanie J Bryant
- Materials Science and Engineering Program, University of Colorado at Boulder, Boulder, CO, USA
- BioFrontiers Institute, University of Colorado at Boulder, Boulder, CO, USA
- Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, CO, USA
| | - Robert R McLeod
- Materials Science and Engineering Program, University of Colorado at Boulder, Boulder, CO, USA
- Department of Electrical, Computer & Energy Engineering, University of Colorado at Boulder, Boulder, CO, USA
| | - Virginia L Ferguson
- Paul M. Rady Department of Mechanical Engineering, University of Colorado at Boulder, 427 UCB, Boulder, CO, 80309, USA.
- Materials Science and Engineering Program, University of Colorado at Boulder, Boulder, CO, USA.
- BioFrontiers Institute, University of Colorado at Boulder, Boulder, CO, USA.
| |
Collapse
|
2
|
Chen Y, Zeng D, Wei G, Liao Z, Liang R, Huang X, Lu WW, Chen Y. Pyroptosis in Osteoarthritis: Molecular Mechanisms and Therapeutic Implications. J Inflamm Res 2024; 17:791-803. [PMID: 38348279 PMCID: PMC10860821 DOI: 10.2147/jir.s445573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 01/20/2024] [Indexed: 02/15/2024] Open
Abstract
Osteoarthritis (OA) is a chronic disease that causes pain and functional impairment by affecting joint tissue. Its global impact is noteworthy, causing significant economic losses and property damage. Despite extensive research, the underlying pathogenesis of OA remain an area of ongoing investigation. It has recently been discovered that the OA progression is significantly influenced by pyroptosis. Pyroptosis is a complex process that involves three pathways culminating in the assembly of Gasdermin-D (GSDMD)-N-terminal (GSDMD-NT) into pores through aggregation on the plasma membrane. The aggregation of GSDMD-NT proteins stimulates the release of inflammatory mediators, such as Interleukin-1β (IL-1β), Interleukin-18 (IL-18), and Matrix Metallopeptidase 13 (MMP13), ultimately leading to cellular lysis. The pyroptosis process in specific cells, including synovial macrophages, fibroblast-like synoviocytes (FLS), chondrocytes, and subchondral osteoblasts, contributs factor to the development of OA. Currently, the specific cells that undergo pyroptosis first are not yet fully understood, and it remains unknown whether pyroptosis in one cell can trigger the same process in other cells. Therefore, targeting pyroptosis could potentially offer a novel treatment approach for OA patients. We present a comprehensive analysis of the molecular mechanisms and key features of pyroptosis. We also outline the current research progress on various aspects, including synovial tissue, articular cartilage, extracellular matrix (ECM), and subchondral bone, with a focus on pyroptosis. The aim is to provide theoretical references for the effective management of OA.
Collapse
Affiliation(s)
- Yeping Chen
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| | - Daofu Zeng
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| | - Guizheng Wei
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| | - Zhidong Liao
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
- Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-Constructed by the Province and Ministry, Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| | - Rongyuan Liang
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| | - Xiajie Huang
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
- Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-Constructed by the Province and Ministry, Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| | - William W Lu
- Department of Orthopedics and Traumatology, the University of Hong Kong, Hong Kong, People’s Republic of China
| | - Yan Chen
- Department of Bone and Joint Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
- Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-Constructed by the Province and Ministry, Guangxi Medical University, Nanning, Guangxi, People’s Republic of China
| |
Collapse
|
3
|
Fraser D, Nguyen T, Kotelsky A, Lee W, Buckley M, Benoit DSW. Hydrogel Swelling-Mediated Strain Induces Cell Alignment at Dentin Interfaces. ACS Biomater Sci Eng 2022; 8:3568-3575. [PMID: 35793542 PMCID: PMC9364318 DOI: 10.1021/acsbiomaterials.2c00566] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Cell and tissue alignment
is a defining feature of periodontal
tissues. Therefore, the development of scaffolds that can guide alignment
of periodontal ligament cells (PDLCs) relative to tooth root (dentin)
surfaces is highly relevant for periodontal tissue engineering. To
control PDLC alignment adjacent to the dentin surface, poly(ethylene
glycol) (PEG)-based hydrogels were explored as a highly tunable matrix
for encapsulating cells and directing their activity. Specifically,
a composite system consisting of dentin blocks, PEG hydrogels, and
PDLCs was created to control PDLC alignment through hydrogel swelling.
PDLCs in composites with minimal hydrogel swelling showed random alignment
adjacent to dentin blocks. In direct contrast, the presence of hydrogel
swelling resulted in PDLC alignment perpendicular to the dentin surface,
with the degree and extension of alignment increasing as a function
of swelling. Replicating this phenomenon with different molds, block
materials, and cells, together with predictive modeling, indicated
that PDLC alignment was primarily a biomechanical response to swelling-mediated
strain. Altogether, this study describes a novel method for inducing
cell alignment adjacent to stiff surfaces through applied strain and
provides a model for the study and engineering of periodontal and
other aligned tissues.
Collapse
Affiliation(s)
- David Fraser
- Eastman Institute for Oral Health, Department of Periodontology, University of Rochester Medical Center, Rochester, New York 14620, United States.,Translational Biomedical Science, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Tram Nguyen
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States
| | - Alexander Kotelsky
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States
| | - Whasil Lee
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Pharmacology & Physiology, University of Rochester Medical Center, Rochester, New York 14642, United States.,Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Mark Buckley
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Danielle S W Benoit
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States.,Department of Chemical Engineering, University of Rochester, Rochester, New York 14627, United States.,Materials Science Program, University of Rochester, Rochester, New York 14627, United States
| |
Collapse
|
4
|
Utroša P, Gradišar Š, Onder OC, Žagar E, Pahovnik D. Synthetic Polypeptide–Polyester PolyHIPEs Prepared by Thiol–Ene Photopolymerization. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Petra Utroša
- Department of Polymer Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Špela Gradišar
- Department of Polymer Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Ozgun Can Onder
- Department of Polymer Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Ema Žagar
- Department of Polymer Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - David Pahovnik
- Department of Polymer Chemistry and Technology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| |
Collapse
|
5
|
Mechanical Static Force Negatively Regulates Vitality and Early Skeletal Development in Zebrafish Embryos. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12062912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Skeletal system development and remodelling is regulated by several different factors, including hormones, cytokines, and mechanical forces. It is known that gravity and pressure stimulate mechanosensors on bone cells which transduce mechanical signals to chemical ones. Nevertheless, few data have been provided about the role of mechanical forces on embryo osteogenesis in vivo. Since the zebrafish is an elective model for developmental studies, in particular on bone formation and tissue mineralization, we analyzed in vivo the effects of a static mechanical force generated by a water column on fertilized zebrafish eggs. The results have shown that an increase in the hydrostatic pressure (HP) of up to 5.9% was lethal for 100% of treated embryos at 48 h post fertilization (hpf). A small decrease in length (−2%) and 49% mortality were found in the +4.4% HP embryos compared with the controls. To analyze skeletal development, we evaluated the number of mineralized vertebral bodies in the trunk at five days post fertilization. The embryos grown under +2.4% HP showed a physiological intramembranous mineralization of vertebral bodies whereas the embryos which grew with +3.4% HP showed a significant decrease in mineralization rate (−54%). Morphological analysis of cartilage and bones in embryos at +3.4% HP revealed a delay of both intramembranous and chondrogenic mineralization, respectively, in axial and head bones, whereas the chondrogenesis appeared normal. These data suggested that developing osteoblasts and different mineralization programs are sensitive to mechanical pressure when applied to early embryogenesis.
Collapse
|
6
|
Hao Z, Xu Z, Wang X, Wang Y, Li H, Chen T, Hu Y, Chen R, Huang K, Chen C, Li J. Biophysical Stimuli as the Fourth Pillar of Bone Tissue Engineering. Front Cell Dev Biol 2021; 9:790050. [PMID: 34858997 PMCID: PMC8630705 DOI: 10.3389/fcell.2021.790050] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 10/26/2021] [Indexed: 01/12/2023] Open
Abstract
The repair of critical bone defects remains challenging worldwide. Three canonical pillars (biomaterial scaffolds, bioactive molecules, and stem cells) of bone tissue engineering have been widely used for bone regeneration in separate or combined strategies, but the delivery of bioactive molecules has several obvious drawbacks. Biophysical stimuli have great potential to become the fourth pillar of bone tissue engineering, which can be categorized into three groups depending on their physical properties: internal structural stimuli, external mechanical stimuli, and electromagnetic stimuli. In this review, distinctive biophysical stimuli coupled with their osteoinductive windows or parameters are initially presented to induce the osteogenesis of mesenchymal stem cells (MSCs). Then, osteoinductive mechanisms of biophysical transduction (a combination of mechanotransduction and electrocoupling) are reviewed to direct the osteogenic differentiation of MSCs. These mechanisms include biophysical sensing, transmission, and regulation. Furthermore, distinctive application strategies of biophysical stimuli are presented for bone tissue engineering, including predesigned biomaterials, tissue-engineered bone grafts, and postoperative biophysical stimuli loading strategies. Finally, ongoing challenges and future perspectives are discussed.
Collapse
Affiliation(s)
- Zhuowen Hao
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Zhenhua Xu
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xuan Wang
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yi Wang
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Hanke Li
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Tianhong Chen
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yingkun Hu
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Renxin Chen
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Kegang Huang
- Wuhan Institute of Proactive Health Management Science, Wuhan, China
| | - Chao Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department of Orthopedics, Hefeng Central Hospital, Enshi, China
| | - Jingfeng Li
- Department of Orthopedics, Zhongnan Hospital of Wuhan University, Wuhan, China
| |
Collapse
|
7
|
Saghati S, Nasrabadi HT, Khoshfetrat AB, Moharamzadeh K, Hassani A, Mohammadi SM, Rahbarghazi R, Fathi Karkan S. Tissue Engineering Strategies to Increase Osteochondral Regeneration of Stem Cells; a Close Look at Different Modalities. Stem Cell Rev Rep 2021; 17:1294-1311. [PMID: 33547591 DOI: 10.1007/s12015-021-10130-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2021] [Indexed: 02/06/2023]
Abstract
The homeostasis of osteochondral tissue is tightly controlled by articular cartilage chondrocytes and underlying subchondral bone osteoblasts via different internal and external clues. As a correlate, the osteochondral region is frequently exposed to physical forces and mechanical pressure. On this basis, distinct sets of substrates and physicochemical properties of the surrounding matrix affect the regeneration capacity of chondrocytes and osteoblasts. Stem cells are touted as an alternative cell source for the alleviation of osteochondral diseases. These cells appropriately respond to the physicochemical properties of different biomaterials. This review aimed to address some of the essential factors which participate in the chondrogenic and osteogenic capacity of stem cells. Elements consisted of biomechanical forces, electrical fields, and biochemical and physical properties of the extracellular matrix are the major determinant of stem cell differentiation capacity. It is suggested that an additional certain mechanism related to signal-transduction pathways could also mediate the chondro-osteogenic differentiation of stem cells. The discovery of these clues can enable us to modulate the regeneration capacity of stem cells in osteochondral injuries and lead to the improvement of more operative approaches using tissue engineering modalities.
Collapse
Affiliation(s)
- Sepideh Saghati
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Tissue Engineering, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Tayefi Nasrabadi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. .,Department of Tissue Engineering, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Ali Baradar Khoshfetrat
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. .,Department of Tissue Engineering, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Keyvan Moharamzadeh
- Hamdan Bin Mohammed College of Dental Medicine (HBMCDM), Mohammed Bin Rashid University of Medicine and Health Sciences (MBRU), Dubai, United Arab Emirates
| | - Ayla Hassani
- Chemical Engineering Faculty, Sahand University of Technology, Tabriz, 51335-1996, Iran
| | - Seyedeh Momeneh Mohammadi
- Department of Anatomical Sciences, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Reza Rahbarghazi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. .,Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Sonia Fathi Karkan
- Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| |
Collapse
|
8
|
Davis S, Roldo M, Blunn G, Tozzi G, Roncada T. Influence of the Mechanical Environment on the Regeneration of Osteochondral Defects. Front Bioeng Biotechnol 2021; 9:603408. [PMID: 33585430 PMCID: PMC7873466 DOI: 10.3389/fbioe.2021.603408] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 01/04/2021] [Indexed: 12/20/2022] Open
Abstract
Articular cartilage is a highly specialised connective tissue of diarthrodial joints which provides a smooth, lubricated surface for joint articulation and plays a crucial role in the transmission of loads. In vivo cartilage is subjected to mechanical stimuli that are essential for cartilage development and the maintenance of a chondrocytic phenotype. Cartilage damage caused by traumatic injuries, ageing, or degradative diseases leads to impaired loading resistance and progressive degeneration of both the articular cartilage and the underlying subchondral bone. Since the tissue has limited self-repairing capacity due its avascular nature, restoration of its mechanical properties is still a major challenge. Tissue engineering techniques have the potential to heal osteochondral defects using a combination of stem cells, growth factors, and biomaterials that could produce a biomechanically functional tissue, representative of native hyaline cartilage. However, current clinical approaches fail to repair full-thickness defects that include the underlying subchondral bone. Moreover, when tested in vivo, current tissue-engineered grafts show limited capacity to regenerate the damaged tissue due to poor integration with host cartilage and the failure to retain structural integrity after insertion, resulting in reduced mechanical function. The aim of this review is to examine the optimal characteristics of osteochondral scaffolds. Additionally, an overview on the latest biomaterials potentially able to replicate the natural mechanical environment of articular cartilage and their role in maintaining mechanical cues to drive chondrogenesis will be detailed, as well as the overall mechanical performance of grafts engineered using different technologies.
Collapse
Affiliation(s)
- Sarah Davis
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Marta Roldo
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Gordon Blunn
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Gianluca Tozzi
- Zeiss Global Centre, School of Mechanical and Design Engineering, University of Portsmouth, Portsmouth, United Kingdom
| | - Tosca Roncada
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| |
Collapse
|
9
|
Wilmoth RL, Ferguson VL, Bryant SJ. A 3D, Dynamically Loaded Hydrogel Model of the Osteochondral Unit to Study Osteocyte Mechanobiology. Adv Healthc Mater 2020; 9:e2001226. [PMID: 33073541 PMCID: PMC7677224 DOI: 10.1002/adhm.202001226] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/18/2020] [Indexed: 12/15/2022]
Abstract
Osteocytes are mechanosensitive cells that orchestrate signaling in bone and cartilage across the osteochondral unit. The mechanisms by which osteocytes regulate osteochondral homeostasis and degeneration in response to mechanical cues remain unclear. This study introduces a novel 3D hydrogel bilayer composite designed to support osteocyte differentiation and bone matrix deposition in a bone-like layer and to recapitulate key aspects of the osteochondral unit's complex loading environment. The bilayer hydrogel is fabricated with a soft cartilage-like layer overlaying a stiff bone-like layer. The bone-like layer contains a stiff 3D-printed hydrogel structure infilled with a soft, degradable, cellular hydrogel. The IDG-SW3 cells embedded within the soft hydrogel mature into osteocytes and produce a mineralized collagen matrix. Under dynamic compressive strains, near-physiological levels of strain are achieved in the bone layer (≤ 0.08%), while the cartilage layer bears the majority of the strains (>99%). Under loading, the model induces an osteocyte response, measured by prostaglandin E2, that is frequency, but not strain, dependent: a finding attributed to altered fluid flow within the composite. Overall, this new hydrogel platform provides a novel approach to study osteocyte mechanobiology in vitro in an osteochondral tissue-mimetic environment.
Collapse
Affiliation(s)
- Rachel L Wilmoth
- Department of Mechanical Engineering, University of Colorado Boulder, 1111 Engineering Drive, Boulder, CO, 80309-0427, USA
| | - Virginia L Ferguson
- Department of Mechanical Engineering, University of Colorado Boulder, 1111 Engineering Drive, Boulder, CO, 80309-0427, USA
- BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave, Boulder, CO, 80309-0596, USA
- Materials Science and Engineering, University of Colorado Boulder, 4001 Discovery Drive, Boulder, CO, 80309, USA
| | - Stephanie J Bryant
- BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave, Boulder, CO, 80309-0596, USA
- Materials Science and Engineering, University of Colorado Boulder, 4001 Discovery Drive, Boulder, CO, 80309, USA
- Department of Chemical and Biological Engineering, University of Colorado Boulder, 3415 Colorado Ave, Boulder, CO, 80309-0596, USA
| |
Collapse
|
10
|
Mao Z, Bi X, Ye F, Shu X, Sun L, Guan J, Ritchie RO, Wu S. Controlled Cryogelation and Catalytic Cross-Linking Yields Highly Elastic and Robust Silk Fibroin Scaffolds. ACS Biomater Sci Eng 2020; 6:4512-4522. [PMID: 33455190 DOI: 10.1021/acsbiomaterials.0c00752] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Silk biomaterials with tunable mechanical properties and biological properties are of special importance for tissue engineering. Here, we fabricated silk fibroin (SF, from Bombyx mori silk) scaffolds from cryogelation under controlled temperature and catalytic cross-linking conditions. Structurally, the cryogelled scaffolds demonstrated a greater β-sheet content but significantly smaller β-sheet domains compared to that without chemical cross-linking and catalyst. Mechanically, the cryogelled scaffolds were softer and highly elastic under tension and compression. The 120% tensile elongation and >85% recoverable compressive strain were among the best properties reported for SF scaffolds. Cyclic compression tests proved the robustness of such scaffolds to resist fatigue. The mechanical properties, as well as the degradation rate of the scaffolds, can be fine-tuned by varying the concentrations of the catalyst and the cross-linker. For biological responses, in vitro rat bone mesenchymal stem cell (rBMSC) culture studies demonstrated that cryogelled SF scaffolds supported better cell attachment and proliferation than the routine freeze-thawed scaffolds. The in vivo subcutaneous implantation results showed excellent histocompatibility and tissue ingrowth for the cryogelled SF scaffolds. This straightforward approach of enhanced elasticity of SF scaffolds and fine-tunability in mechanical performances, suggests a promising strategy to develop novel SF biomaterials for soft tissue engineering and regenerative medicine.
Collapse
Affiliation(s)
- Zhinan Mao
- International Research Center for Advanced Structural and Biomaterials, School of Materials Science & Engineering, Beihang University, Beijing 100191, China
| | - Xuewei Bi
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beijing 100083, China
| | - Fan Ye
- International Research Center for Advanced Structural and Biomaterials, School of Materials Science & Engineering, Beihang University, Beijing 100191, China
| | - Xiong Shu
- Beijing Research Institute of Traumatology & Orthopaedics, Beijing 100035, China
| | - Lei Sun
- Beijing Research Institute of Traumatology & Orthopaedics, Beijing 100035, China
| | - Juan Guan
- International Research Center for Advanced Structural and Biomaterials, School of Materials Science & Engineering, Beihang University, Beijing 100191, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beijing 100083, China
| | - Robert O Ritchie
- Department of Materials Science & Engineering, University of California, Berkeley, California 94720, United States
| | - Sujun Wu
- International Research Center for Advanced Structural and Biomaterials, School of Materials Science & Engineering, Beihang University, Beijing 100191, China
| |
Collapse
|
11
|
Schneider MC, Lalitha Sridhar S, Vernerey FJ, Bryant SJ. Spatiotemporal neocartilage growth in matrix-metalloproteinase-sensitive poly(ethylene glycol) hydrogels under dynamic compressive loading: an experimental and computational approach. J Mater Chem B 2020; 8:2775-2791. [PMID: 32155233 PMCID: PMC7695218 DOI: 10.1039/c9tb02963j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Enzyme-sensitive hydrogels containing encapsulated chondrocytes are a promising platform for cartilage tissue engineering. However, the growth of neotissue is closely coupled to the degradation of the hydrogel and is further complicated due to the encapsulated cells serving as the enzyme source for hydrogel degradation. To better understand these coupled processes, this study combined experimental and computational methods to analyze the transition from hydrogel to neotissue in a biomimetic MMP-sensitive poly(ethylene glycol) (PEG) hydrogel with encapsulated chondrocytes. A physics-based computational model that describes spatial heterogeneities in cell distribution was used. Experimentally, cell-laden hydrogels were cultured for six weeks under free swelling or subjected daily to one-hour of dynamic compressive loading. Extracellular matrix (ECM) synthesis rates were used as model inputs, and the model was fit to the experimentally determined construct modulus over time for the free swelling condition. Experimentally, ECM accumulation comprising collagen II and aggrecan increased over time concomitant with hydrogel degradation observed by a loss in PEG. Simulations demonstrated rapid degradation in regions of high cell density (i.e., cell clusters) reaching complete degradation by day 13, which facilitated localized ECM growth. Regions of low cell density degraded more slowly, had limited ECM, and led to the decrease in construct modulus during the first two weeks. The primary difference between the two culture environments was greater ECM accumulation in the clusters under free swelling, which facilitated a faster recovery in construct modulus. By 6 weeks the compressive modulus increased 2.5-fold to 107 kPa under free swelling, but dropped 1.6-fold to 26 kPa under loading. In summary, this biomimetic MMP-sensitive hydrogel supports neocartilage growth by facilitating rapid ECM growth within cell clusters, which was followed by slower growth in the rest of the hydrogel. Subtle temporal differences in hydrogel degradation and ECM accumulation, however, had a significant impact on the evolving mechanical properties.
Collapse
Affiliation(s)
- Margaret C Schneider
- Department of Chemical and Biological Engineering, University of Colorado, 3415 Colorado Ave., Boulder, Colorado 80309-0596, USA.
| | - Shankar Lalitha Sridhar
- Department of Mechanical Engineering, University of Colorado, 1111 Engineering Dr., Boulder, Colorado 80309-0596, USA.
| | - Franck J Vernerey
- Department of Mechanical Engineering, University of Colorado, 1111 Engineering Dr., Boulder, Colorado 80309-0596, USA. and Materials Science and Engineering Program, University of Colorado, 3415 Colorado Ave., Boulder, Colorado 80309-0596, USA
| | - Stephanie J Bryant
- Department of Chemical and Biological Engineering, University of Colorado, 3415 Colorado Ave., Boulder, Colorado 80309-0596, USA. and Materials Science and Engineering Program, University of Colorado, 3415 Colorado Ave., Boulder, Colorado 80309-0596, USA and Biofrontiers Institute, University of Colorado, 3415 Colorado Ave., Boulder, Colorado 80309-0596, USA
| |
Collapse
|
12
|
Abstract
Human bones have unique structures and characteristics, and replacing a natural bone in the case of bone fracture or bone diseases is a very complicated problem. The main goal of this paper was to summarize the recent research on polymer materials as bone substitutes and for bone repair. Bone treatment methods, bone substitute materials as well as their advantages and drawbacks, and manufacturing methods were reviewed. Biopolymers are the most promising materials in the field of artificial bones and using biopolymers with the shape memory effect can improve the integration of an artificial bone into the human body by better mimicking the structure and properties of natural bones, decreasing the invasiveness of surgical procedures by producing deployable implants. It has been shown that the application of the rapid prototyping technology for artificial bones allows the customization of bone substitutes for a patient and the creation of artificial bones with a complex structure.
Collapse
Affiliation(s)
- Anastasiia Kashirina
- Department of Astronautical Science and Mechanics, Harbin Institute of Technology, PO Box 301, No. 92 West Dazhi Street, Harbin 150001, China
| | - Yongtao Yao
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, No. 2 YiKuang Street, Harbin 150080, China.
| | - Yanju Liu
- Department of Astronautical Science and Mechanics, Harbin Institute of Technology, PO Box 301, No. 92 West Dazhi Street, Harbin 150001, China
| | - Jinsong Leng
- National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, No. 2 YiKuang Street, Harbin 150080, China.
| |
Collapse
|