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Guo S, Yan M, Li X, Zhang S, Liu Z, Li K, Liu P, Liu Y, Sun G, Fu Q. Single-cell RNA-seq analysis reveals that immune cells induce human nucleus pulposus ossification and degeneration. Front Immunol 2023; 14:1224627. [PMID: 37638033 PMCID: PMC10449260 DOI: 10.3389/fimmu.2023.1224627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/24/2023] [Indexed: 08/29/2023] Open
Abstract
Background and aims Determining the transcriptomes and molecular mechanism underlying human degenerative nucleus pulposus (NP) is of critical importance for treating intervertebral disc degeneration (IDD). Here, we aimed to elucidate the detailed molecular mechanism of NP ossification and IDD using single-cell RNA sequencing. Methods Single-cell RNA-seq and bioinformatic analysis were performed to identify NP cell populations with gene signatures, biological processes and pathways, and subpopulation analysis, RNA velocity analysis, and cell-to-cell communication analysis were performed in four IDD patients. We also verified the effects of immune cells on NP ossification using cultured NP cells and a well-established rat IDD model. Results We identified five cell populations with gene expression profiles in degenerative NP at single-cell resolution. GO database analysis showed that degenerative NP-associated genes were mainly enriched in extracellular matrix organization, immune response, and ossification. Gene set enrichment analysis showed that rheumatoid arthritis signaling, antigen processing and presentation signaling were activated in the blood cell cluster. We revealed that stromal cells, which are progenitor cells, differentiated toward an ossification phenotype and delineated interactions between immune cells (macrophages and T cells) and stromal cells. Immune factors such as TNF-α, CD74 and CCL-3 promoted the differentiation of stromal cells toward an ossification phenotype in vitro. Blocking TNF-α with a specific inhibitor successfully reversed NP ossification and modified NP morphology in vivo. Conclusion Our study revealed an increase in macrophages and T cells in degenerative NP, which induced stromal cell differentiation toward an ossification phenotype, and contributed to the identification of a novel therapeutic target to delay IDD.
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Affiliation(s)
- Song Guo
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Meijun Yan
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Xinhua Li
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Shuya Zhang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States
| | - Zhong Liu
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Kewei Li
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Pengcheng Liu
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Yanbin Liu
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
| | - Guixin Sun
- Department of Traumatology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Qiang Fu
- Department of Spine Surgery, Shanghai Jiaotong University First People’s Hospital, Shanghai, China
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2
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Zhang A, Cheng Z, Chen Y, Shi P, Gan W, Zhang Y. Emerging tissue engineering strategies for annulus fibrosus therapy. Acta Biomater 2023:S1742-7061(23)00337-9. [PMID: 37330029 DOI: 10.1016/j.actbio.2023.06.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 05/31/2023] [Accepted: 06/12/2023] [Indexed: 06/19/2023]
Abstract
Low back pain is a major public health concern experienced by 80% of the world's population during their lifetime, which is closely associated with intervertebral disc (IVD) herniation. IVD herniation manifests as the nucleus pulposus (NP) protruding beyond the boundaries of the intervertebral disc due to disruption of the annulus fibrosus (AF). With a deepening understanding of the importance of the AF structure in the pathogenesis of intervertebral disc degeneration, numerous advanced therapeutic strategies for AF based on tissue engineering, cellular regeneration, and gene therapy have emerged. However, there is still no consensus concerning the optimal approach for AF regeneration. In this review, we summarized strategies in the field of AF repair and highlighted ideal cell types and pro-differentiation targeting approaches for AF repair, and discussed the prospects and difficulties of implant systems combining cells and biomaterials to guide future research directions. STATEMENT OF SIGNIFICANCE: Low back pain is a major public health concern experienced by 80% of the world's population during their lifetime, which is closely associated with intervertebral disc (IVD) herniation. However, there is still no consensus concerning the optimal approach for annulus fibrosus (AF) regeneration. In this review, we summarized strategies in the field of AF repair and highlighted ideal cell types and pro-differentiation targeting approaches for AF repair, and discussed the prospects and difficulties of implant systems combining cells and biomaterials to guide future research directions.
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Affiliation(s)
- Anran Zhang
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Zhangrong Cheng
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yuhang Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Pengzhi Shi
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Weikang Gan
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yukun Zhang
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
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Lazaro-Pacheco D, Mohseni M, Rudd S, Cooper-White J, Holsgrove TP. The role of biomechanical factors in models of intervertebral disc degeneration across multiple length scales. APL Bioeng 2023; 7:021501. [PMID: 37180733 PMCID: PMC10168717 DOI: 10.1063/5.0137698] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 04/24/2023] [Indexed: 05/16/2023] Open
Abstract
Low back pain is the leading cause of disability, producing a substantial socio-economic burden on healthcare systems worldwide. Intervertebral disc (IVD) degeneration is a primary cause of lower back pain, and while regenerative therapies aimed at full functional recovery of the disc have been developed in recent years, no commercially available, approved devices or therapies for the regeneration of the IVD currently exist. In the development of these new approaches, numerous models for mechanical stimulation and preclinical assessment, including in vitro cell studies using microfluidics, ex vivo organ studies coupled with bioreactors and mechanical testing rigs, and in vivo testing in a variety of large and small animals, have emerged. These approaches have provided different capabilities, certainly improving the preclinical evaluation of these regenerative therapies, but challenges within the research environment, and compromises relating to non-representative mechanical stimulation and unrealistic test conditions, remain to be resolved. In this review, insights into the ideal characteristics of a disc model for the testing of IVD regenerative approaches are first assessed. Key learnings from in vivo, ex vivo, and in vitro IVD models under mechanical loading stimulation to date are presented alongside the merits and limitations of each model based on the physiological resemblance to the human IVD environment (biological and mechanical) as well as the possible feedback and output measurements for each approach. When moving from simplified in vitro models to ex vivo and in vivo approaches, the complexity increases resulting in less controllable models but providing a better representation of the physiological environment. Although cost, time, and ethical constraints are dependent on each approach, they escalate with the model complexity. These constraints are discussed and weighted as part of the characteristics of each model.
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Affiliation(s)
- Daniela Lazaro-Pacheco
- Department of Engineering, University of Exeter, Harrison Building, Streatham Campus, North Park Road, Exeter EX4 4QF, United Kingdom
| | - Mina Mohseni
- School of Chemical Engineering, The University of Queensland, St. Lucia QLD 4072, Australia
| | - Samuel Rudd
- School of Chemical Engineering, The University of Queensland, St. Lucia QLD 4072, Australia
| | | | - Timothy Patrick Holsgrove
- Department of Engineering, University of Exeter, Harrison Building, Streatham Campus, North Park Road, Exeter EX4 4QF, United Kingdom
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4
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Wei Q, Liu D, Chu G, Yu Q, Liu Z, Li J, Meng Q, Wang W, Han F, Li B. TGF-β1-supplemented decellularized annulus fibrosus matrix hydrogels promote annulus fibrosus repair. Bioact Mater 2023; 19:581-593. [PMID: 35600980 PMCID: PMC9108517 DOI: 10.1016/j.bioactmat.2022.04.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/06/2022] [Accepted: 04/23/2022] [Indexed: 12/19/2022] Open
Abstract
Annulus fibrosus (AF) repair remains a challenge because of its limited self-healing ability. Endogenous repair strategies combining scaffolds and growth factors show great promise in AF repair. Although the unique and beneficial characteristics of decellularized extracellular matrix (ECM) in tissue repair have been demonstrated, the poor mechanical property of ECM hydrogels largely hinders their applications in tissue regeneration. In the present study, we combined polyethylene glycol diacrylate (PEGDA) and decellularized annulus fibrosus matrix (DAFM) to develop an injectable, photocurable hydrogel for AF repair. We found that the addition of PEGDA markedly improved the mechanical strength of DAFM hydrogels while maintaining their porous structure. Transforming growth factor-β1 (TGF-β1) was further incorporated into PEGDA/DAFM hydrogels, and it could be continuously released from the hydrogel. The in vitro experiments showed that TGF-β1 facilitated the migration of AF cells. Furthermore, PEGDA/DAFM/TGF-β1 hydrogels supported the adhesion, proliferation, and increased ECM production of AF cells. In vivo repair performance of the hydrogels was assessed using a rat AF defect model. The results showed that the implantation of PEGDA/DAFM/TGF-β1 hydrogels effectively sealed the AF defect, prevented nucleus pulposus atrophy, retained disc height, and partially restored the biomechanical properties of disc. In addition, the implanted hydrogel was infiltrated by cells resembling AF cells and well integrated with adjacent AF tissue. In summary, findings from this study indicate that TGF-β1-supplemented DAFM hydrogels hold promise for AF repair. Injectable DAFM derived hydrogel with mechanical property matching natural AF and sustained TGF-β1 release was developed. DAFM derived hydrogels promote AF cell proliferation, migration and ECM production. DAFM derived hydrogels display good integration with host AF tissue. DAFM derived hydrogels facilitate AF repair and restore intervertebral disc biomechanics.
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Affiliation(s)
- Qiang Wei
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Dachuan Liu
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Genglei Chu
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Qifan Yu
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Zhao Liu
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Jiaying Li
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Qingchen Meng
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
| | - Weishan Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang, China
- Corresponding author.
| | - Fengxuan Han
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
- Corresponding author.
| | - Bin Li
- Department of Orthopaedic Surgery, Orthopaedic Institute, The First Affiliated Hospital, Suzhou Medical College, Soochow University, Suzhou, Jiangsu, China
- Department of Orthopaedic Surgery, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang, China
- Collaborative Innovation Center of Hematology, Soochow University, Suzhou, Jiangsu, China
- Corresponding author. Soochow University (North Campus), 178 Ganjiang Rd, Suzhou, Jiangsu, 215007, China.
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5
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Constant C, Hom WW, Nehrbass D, Carmel E, Albers CE, Deml MC, Gehweiler D, Lee Y, Hecht A, Grad S, Iatridis JC, Zeiter S. Comparison and optimization of sheep in vivo intervertebral disc injury model. JOR Spine 2022; 5:e1198. [PMID: 35783908 PMCID: PMC9238284 DOI: 10.1002/jsp2.1198] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 03/08/2022] [Accepted: 03/16/2022] [Indexed: 11/09/2022] Open
Abstract
Background The current standard of care for intervertebral disc (IVD) herniation, surgical discectomy, does not repair annulus fibrosus (AF) defects, which is partly due to the lack of effective methods to do so and is why new repair strategies are widely investigated and tested preclinically. There is a need to develop a standardized IVD injury model in large animals to enable comparison and interpretation across preclinical study results. The purpose of this study was to compare in vivo IVD injury models in sheep to determine which annulus fibrosus (AF) defect type combined with partial nucleus pulposus (NP) removal would better mimic degenerative human spinal pathologies. Methods Six skeletally mature sheep were randomly assigned to one of the two observation periods (1 and 3 months) and underwent creation of 3 different AF defect types (slit, cruciate, and box-cut AF defects) in conjunction with 0.1 g NP removal in three lumbar levels using a lateral retroperitoneal surgical approach. The spine was monitored by clinical CT scans pre- and postoperatively, at 2 weeks and euthanasia, and by magnetic resonance imaging (MRI) and histology after euthanasia to determine the severity of degeneration (disc height loss, Pfirrmann grading, semiquantitative histopathology grading). Results All AF defects led to significant degenerative changes detectable on CT and MR images, produced bulging of disc tissue without disc herniation and led to degenerative and inflammatory histopathological changes. However, AF defects were not equal in terms of disc height loss at 3 months postoperatively; the cruciate and box-cut AF defects showed significantly decreased disc height compared to their preoperative height, with the box-cut defect creating the greatest disc height loss, while the slit AF defect showed restoration of normal preoperative disc height. Conclusions The tested IVD injury models do not all generate comparable disc degeneration but can be considered suitable IVD injury models to investigate new treatments. Results of the current study clearly indicate that slit AF defect should be avoided if disc height is used as one of the main outcomes; additional confirmatory studies may be warranted to generalize this finding.
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Affiliation(s)
| | - Warren W. Hom
- Department of OrthopaedicsIcahn School of Medicine, Mount Sinai Health SystemNew YorkNew YorkUSA
| | | | - Eric‐Norman Carmel
- Département de sciences cliniques, Faculté de médecine vétérinaireUniversité de MontréalSaint‐HyacintheCanada
| | - Christoph E. Albers
- Department of Orthopaedic Surgery & TraumatologyInselspital, University Hospital BernBernSwitzerland
| | - Moritz C. Deml
- Department of Orthopaedic Surgery & TraumatologyInselspital, University Hospital BernBernSwitzerland
| | | | - Yunsoo Lee
- Department of OrthopaedicsIcahn School of Medicine, Mount Sinai Health SystemNew YorkNew YorkUSA
| | - Andrew Hecht
- Department of OrthopaedicsIcahn School of Medicine, Mount Sinai Health SystemNew YorkNew YorkUSA
| | | | - James C. Iatridis
- Department of OrthopaedicsIcahn School of Medicine, Mount Sinai Health SystemNew YorkNew YorkUSA
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6
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Wang H, Wang D, Luo B, Wang D, Jia H, Peng P, Shang Q, Mao J, Gao C, Peng Y, Gan L, Du J, Luo Z, Yang L. Decoding the annulus fibrosus cell atlas by scRNA-seq to develop an inducible composite hydrogel: A novel strategy for disc reconstruction. Bioact Mater 2022; 14:350-363. [PMID: 35386822 PMCID: PMC8964821 DOI: 10.1016/j.bioactmat.2022.01.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/22/2022] [Accepted: 01/23/2022] [Indexed: 02/08/2023] Open
Abstract
Low back pain is one of the most serious public health problems worldwide and the major clinical manifestation of intervertebral disc degeneration (IVDD). The key pathological change during IVDD is dysfunction of the annulus fibrosus (AF). However, due to the lack of an in-depth understanding of AF biology, the methods to reconstruct the AF are very limited. In this study, the mice AF cell atlas were decoded by single-cell RNA sequencing to provide a guide for AF reconstruction. The results first identify a new population of AF cells, fibrochondrocyte-like AF cells, which synthesize both collagen I and collagen II and are potential functional cells for AF reconstruction. According to the dual features of the AF extracellular matrix, a composite hydrogel based on the acylation of methacrylated silk fibroin with methacrylated hyaluronic acid was produced. To obtain the ability to stimulate differentiation, the composite hydrogels were combined with a fibrochondrocyte-inducing supplement. Finally, reconstruction of the AF defects, by the novel AF stem cell-loaded composite hydrogel, could be observed, its amount of chondroid matrices recovered to 31.7% of AF aera which is significantly higher than that in other control groups. In summary, this study decodes the AF cell atlas, based on which a novel strategy for AF reconstruction is proposed. There are 10 populations of cells in the annulus fibrosus (AF), as decoded by single cell RNA sequencing. Lineage tracing shows the route of migration and differentiation of annulus fibrosus-derived stem cells (AFSCs). A new population of AF cells, fibrochondrocyte-like AF cells, was identified. Both the fibrinoid and chondroid matrices of AF are reconstructed by the novel AFSCs-loaded composite hydrogel.
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7
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Kirnaz S, Singh S, Capadona C, Lintz M, Goldberg JL, McGrath LB, Medary B, Sommer F, Bonassar LJ, Härtl R. Innovative Biological Treatment Methods for Degenerative Disc Disease. World Neurosurg 2021; 157:282-299. [PMID: 34929786 DOI: 10.1016/j.wneu.2021.09.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 10/19/2022]
Abstract
Low back pain is the leading cause of work absences and years lived with disability, and it is often associated with degenerative disc disease. In recent years, biological treatment approaches such as the use of growth factors, cell injections, annulus fibrosus (AF) repair, nucleus pulposus replacement, and tissue-engineered discs have been explored as means for preventing or reversing degenerative disc disease. Both animal and clinical studies have shown promising results for cell-based therapy on the grounds of its regenerative potential. Clinical data also indicate that stem cell injection is safe when appropriately performed, albeit its long-term safety and efficacy are yet to be explored. Numerous challenges also remain to be overcome, such as isolating, differentiating, and preconditioning the disc cells, as well as managing the nutrient-deficient and oxygen-deficient micromilieu of the intervertebral disc (IVD). AF repair methods including devices used in clinical trials have shown success in decreasing reherniation rates and improving overall clinical outcomes. In addition, recent studies that combined AF repair and nucleus pulposus replacement have shown improved biomechanical stability in IVDs after the combined treatment. Tissue-engineered IVDs for total disc replacement are still being developed, and future studies are necessary to overcome the challenges in their delivery, efficacy, and safety.
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Affiliation(s)
- Sertac Kirnaz
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Sunidhi Singh
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Charisse Capadona
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Marianne Lintz
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Jacob L Goldberg
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Lynn B McGrath
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Branden Medary
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Fabian Sommer
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York, USA; Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York, USA
| | - Roger Härtl
- Department of Neurological Surgery, Weill Cornell Medicine Brain and Spine Center, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
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8
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Marshall SL, Jacobsen TD, Emsbo E, Murali A, Anton K, Liu JZ, Lu HH, Chahine NO. Three-Dimensional-Printed Flexible Scaffolds Have Tunable Biomimetic Mechanical Properties for Intervertebral Disc Tissue Engineering. ACS Biomater Sci Eng 2021; 7:5836-5849. [PMID: 34843224 DOI: 10.1021/acsbiomaterials.1c01326] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The intervertebral disc (IVD) exhibits complex structure and biomechanical function, which supports the weight of the body and permits motion. Surgical treatments for IVD degeneration (e.g., lumbar fusion, disc replacement) often disrupt the mechanical environment of the spine which lead to adjacent segment disease. Alternatively, disc tissue engineering strategies, where cell-seeded hydrogels or fibrous biomaterials are cultured in vitro to promote matrix deposition, do not recapitulate the complex IVD mechanical properties. In this study, we use 3D printing of flexible polylactic acid (FPLA) to fabricate a viscoelastic scaffold with tunable biomimetic mechanics for whole spine motion segment applications. We optimized the mechanical properties of the scaffolds for equilibrium and dynamic moduli in compression and tension by varying fiber spacing or porosity, generating scaffolds with de novo mechanical properties within the physiological range of spine motion segments. The biodegradation analysis of the 3D printed scaffolds showed that FPLA exhibits lower degradation rate and thus has longer mechanical stability than standard PLA. FPLA scaffolds were biocompatible, supporting viability of nucleus pulposus (NP) cells in 2D and in FPLA+hydrogel composites. Composite scaffolds cultured with NP cells maintained baseline physiological mechanical properties and promoted matrix deposition up to 8 weeks in culture. Mesenchymal stromal cells (MSCs) cultured on FPLA adhered to the scaffold and exhibited fibrocartilaginous differentiation. These results demonstrate for the first time that 3D printed FPLA scaffolds have de novo viscoelastic mechanical properties that match the native IVD motion segment in both tension and compression and have the potential to be used as a mechanically stable and biocompatible biomaterial for engineered disc replacement.
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Affiliation(s)
- Samantha L Marshall
- Department of Orthopedic Surgery, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Timothy D Jacobsen
- Department of Orthopedic Surgery, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States.,Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Erik Emsbo
- Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Archana Murali
- Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Kevin Anton
- Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Jessica Z Liu
- Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Helen H Lu
- Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
| | - Nadeen O Chahine
- Department of Orthopedic Surgery, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States.,Department of Biomedical Engineering, Columbia University, 650 West 168th Street, 1410, New York, New York 10031, United States
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9
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Peredo AP, Gullbrand SE, Smith HE, Mauck RL. Putting the Pieces in Place: Mobilizing Cellular Players to Improve Annulus Fibrosus Repair. TISSUE ENGINEERING. PART B, REVIEWS 2021; 27:295-312. [PMID: 32907498 PMCID: PMC10799291 DOI: 10.1089/ten.teb.2020.0196] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The intervertebral disc (IVD) is an integral load-bearing tissue that derives its function from its composite structure and extracellular matrix composition. IVD herniations involve the failure of the annulus fibrosus (AF) and the extrusion of the nucleus pulposus beyond the disc boundary. Disc herniations can impinge the neural elements and cause debilitating pain and loss of function, posing a significant burden on individual patients and society as a whole. Patients with persistent symptoms may require surgery; however, surgical intervention fails to repair the ruptured AF and is associated with the risk for reherniation and further disc degeneration. Given the limitations of AF endogenous repair, many attempts have been made toward the development of effective repair approaches that reestablish IVD function. These methods, however, fail to recapitulate the composition and organization of the native AF, ultimately resulting in inferior tissue mechanics and function over time and high rates of reherniation. Harnessing the cellular function of cells (endogenous or exogenous) at the repair site through the provision of cell-instructive cues could enhance AF tissue regeneration and, ultimately, improve healing outcomes. In this study, we review the diverse approaches that have been developed for AF repair and emphasize the potential for mobilizing the appropriate cellular players at the site of injury to improve AF healing. Impact statement Conventional treatments for intervertebral disc herniation fail to repair the annulus fibrosus (AF), increasing the risk for recurrent herniation. The lack of repair devices in the market has spurred the development of regenerative approaches, yet most of these rely on a scarce endogenous cell population to repair large injuries, resulting in inadequate regeneration. This review identifies current and developing strategies for AF repair and highlights the potential for harnessing cellular function to improve AF regeneration. Ideal cell sources, differentiation strategies, and delivery methods are discussed to guide the design of repair systems that leverage specialized cells to achieve superior outcomes.
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Affiliation(s)
- Ana P. Peredo
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Sarah E. Gullbrand
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Harvey E. Smith
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Robert L. Mauck
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
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10
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Sloan SR, Wipplinger C, Kirnaz S, Navarro-Ramirez R, Schmidt F, McCloskey D, Pannellini T, Schiavinato A, Härtl R, Bonassar LJ. Combined nucleus pulposus augmentation and annulus fibrosus repair prevents acute intervertebral disc degeneration after discectomy. Sci Transl Med 2021; 12:12/534/eaay2380. [PMID: 32161108 DOI: 10.1126/scitranslmed.aay2380] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 02/10/2020] [Indexed: 12/12/2022]
Abstract
Tissue-engineered approaches for the treatment of early-stage intervertebral disc degeneration have shown promise in preclinical studies. However, none of these therapies has been approved for clinical use, in part because each therapy targets only one aspect of the intervertebral disc's composite structure. At present, there is no reliable method to prevent intervertebral disc degeneration after herniation and subsequent discectomy. Here, we demonstrate the prevention of degeneration and maintenance of mechanical function in the ovine lumbar spine after discectomy by combining strategies for nucleus pulposus augmentation using hyaluronic acid injection and repair of the annulus fibrosus using a photocrosslinked collagen patch. This combined approach healed annulus fibrosus defects, restored nucleus pulposus hydration, and maintained native torsional and compressive stiffness up to 6 weeks after injury. These data demonstrate the necessity of a combined strategy for arresting intervertebral disc degeneration and support further translation of combinatorial interventions to treat herniations in the human spine.
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Affiliation(s)
- Stephen R Sloan
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Christoph Wipplinger
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
| | - Sertaç Kirnaz
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
| | | | - Franziska Schmidt
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
| | - Duncan McCloskey
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Tania Pannellini
- Pathology and Laboratory Medicine, Hospital for Special Surgery, New York, NY 10065, USA
| | | | - Roger Härtl
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA. .,Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA
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11
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Xia D, Yan M, Yin X, Hu W, Zhang C, Hu B, Ge T, Wu X, Xiao J, Gao L, Liu J, Tan J. A Novel Rat Tail Needle Minimally Invasive Puncture Model Using Three-Dimensional Printing for Disk Degeneration and Progressive Osteogenesis Research. Front Cell Dev Biol 2021; 9:587399. [PMID: 34150742 PMCID: PMC8209544 DOI: 10.3389/fcell.2021.587399] [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: 07/26/2020] [Accepted: 04/06/2021] [Indexed: 11/17/2022] Open
Abstract
Many studies focused on the annulus fibrosus (AF) injury in rodent tail model for the intervertebral disk degeneration (IDD) research. However, previous studies caused tremendous injury of intervertebral disk (IVD) by penetrating whole disk. This study aimed to build a progressive IDD rodent tail model by a novel device for precise and minimally invasive puncture in AF. A precise puncture device was customized by 3D Printing Technique. 40 rodent tail IVDs were randomly grouped as follows: group A, non-puncture; group B, annulus needle puncture (ANP) for 4 week; group C, ANP for 8 week; and group D, ANP for 12 week. Pre- and post-puncture IVD height on radiographs and IVD signal intensity on T2 magnetic resonance imaging (MRI) were measured. Average bone density (ABD) on the end of coccygeal vertebrae between punctured disk was measured on the radiographs. Hematoxylin and eosin, TUNEL staining methods, immunofluorescence for cleaved-caspas3 and immunohistochemistry for aggrecan and collagen II were performed. Progressively and significantly increasing IVD height loss and degenerative grade were observed following the time points. The ABD was respectively, 81.20 ± 4.63 in group A, 83.93±3.18 in group B, 92.65 ± 4.32 in group C, 98.87 ± 6.69 in group D. In both group C and group D, there were significant differences with group A. In histology, increasing number of AF cells was noted in group B. In both group C and D, the fissures in AF were obviously observed, and a marked reduction of AF cells were also observed. In all ANP groups, there were significant decrease in number of NP cells, as well as aggrecan and collagen II contents. TUNEL assay showed cellular apoptosis were stimulated in all puncture group, especially in group D. A progressive IDD rat model could be standardly established by the micro-injury IVD puncture using a novel 3D printing device. This animal model provided a potential application for research of progressive hyperosteogeny following IDD development.
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Affiliation(s)
- Dongdong Xia
- Department of Orthopedics, Ningbo First Hospital, Ningbo, China
| | - Meijun Yan
- Department of Orthopaedics, Shanghai General Hospital, Shanghai, China
| | - Xin Yin
- Department of Orthopedics, Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Wenhao Hu
- Department of Orthopedics, Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Chi Zhang
- Department of Orthopedics, Ningbo First Hospital, Ningbo, China
| | - Baiwen Hu
- Department of Orthopedics, Ningbo First Hospital, Ningbo, China
| | - Ting Ge
- Department of Orthopedics, Ningbo First Hospital, Ningbo, China
| | - Xiaochuan Wu
- Department of Orthopedics, Ningbo First Hospital, Ningbo, China
| | - Jin Xiao
- Department of Orthopedics, Ningbo First Hospital, Ningbo, China
| | - Liang Gao
- Center for Clinical Medicine, Hua Tuo Institute of Medical Innovation (HTIMI), Wuhan, China
| | - Junqi Liu
- Department of Radiotherapy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jun Tan
- Department of Orthopedics, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
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12
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Xiang X, HePing Y, YiMin W, ShuWen L, JunFeng W, Jian Z, ZhiCai D, YingNan Y, Yuan Z. Morphology Comparison Between Goat Bone Marrow Mesenchymal Stem Cells and Adhesive Fibrin for the Repair of Annulus Fibrosus Defect of Intervertebral Discs. J BIOMATER TISS ENG 2021. [DOI: 10.1166/jbt.2021.2731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Introduction: The purpose of this study was to compare the histological findings of goat bone marrow mesenchymal stem cell (BMSC) transplantation and adhesive fibrin repair for annulus fibrosus defects in intervertebral discs. Material and methods: The goats were spanided
into three groups: the control group, the adhesive group and the transplantation group. In the control group, surgical instruments were used to create a fibrous ring defect in the intervertebral disc of the goats. In the adhesive group, a 1.5*1.5-cm defect was also created by surgical intervention,
and the broken fiber ring was then bonded with adhesive fibrin. In the transplantation group, a gelatine sponge containing the goat BMSCs was implanted into the broken annulus fibrosus, and the wound was closed layer by layer. At 6 weeks and 12 weeks after the operation, the damaged tissues
were removed, and haematoxylin and eosin (HE), trichrome gelatine (Masson), Alcian blue periodic acid-Schiff (AB-PAS) and Collagen II staining was performed. Then, the tissues from the different groups were histologically compared and analyzed. Results: Goat BMSCs have a better ability
to repair defects in the fibrous ring than adhesive fibrin. Over time, the number of cells or the amount of tissue following cell transplantation was greater, indicating that the degree of repair is greater with BMSCs than with adhesive fibrin. Conclusion: Histologically, repair of
the defect of the fibrous ring and prevention of nucleus pulposus protrusion were more effective in the cell transplantation group than in the other two groups.
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Affiliation(s)
- Xu Xiang
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Yin HePing
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Wu YiMin
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Li ShuWen
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Wang JunFeng
- Department of Medical Engineering Department, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Zhao Jian
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Du ZhiCai
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Yu YingNan
- Department of Minimally Invasive Spinal Surgery, The Second Affiliated Hospital of Inner Mongolia Medical College, Huhhot 010030, Inner Mongolia, China
| | - Zhang Yuan
- Department of Anesthesiology, Inner Mongolia International Hospital, Huhhot 010030, Inner Mongolia, China
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Analysis of the influence of species, intervertebral disc height and Pfirrmann classification on failure load of an injured disc using a novel disc herniation model. Spine J 2021; 21:698-707. [PMID: 33157322 DOI: 10.1016/j.spinee.2020.10.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/25/2020] [Accepted: 10/28/2020] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Annular repair devices offer a solution to recurrent disc herniations by closing an annular defect and lowering the risk of reherniation. Given the significant risk of neurologic injury from device failure it is imperative that a reliable preclinical model exists to demonstrate a high load to failure for the disc repair devices. PURPOSE To establish a preclinical model for disc herniation and demonstrate how changes in species, intervertebral disc height and Pfirrmann classification impacts failure load on an injured disc. We hypothesized that: (1) The force required for disc herniation would be variable across disc morphologies and species, and (2) for human discs the force to herniation would inversely correlate with the degree of disc degeneration. STUDY DESIGN Animal and human cadaveric biomechanical model of disc herniation. METHODS We tested calf lumbar spines, bovine tail segments and human lumbar spines. We first divided individual lumbar or tail segments to include the vertebral bodies and disc. We then hydrated the specimens by placing them in a saline bath overnight. A magnetic resonance images were acquired from human specimens and a Pfirrmann classification was made. A stab incision measuring 25% of the diameter of the disc was then done to each specimen along the posterior intervertebral disc space. Each specimen was placed in custom test fixtures on a servo-hydraulic test frame (MTS, Eden Prarie, MN) such that the superior body was attached to a 10,000 lb load cell and the inferior body was supported on the piston. A compressive ramping load was placed on the specimen in load control at 4 MPa/sec stopping at 75% of the disc height. Load was recorded throughout the test and failure load calculated. Once the test was completed each specimen was sliced through the center of the disc and photos were taken of the cut surface. RESULTS Fifteen each of calf, human, and bovine tail segments were tested. The failure load varied significantly between specimens (p<.001) with human specimens having the highest average failure load (8154±2049 N). Disc height was higher for lumbar/bovine tail segments as compared to calf specimens (p<.001) with bovine tails having the highest disc height (7.1±1.7 mm). Similarly, human lumbar discs had a cross sectional area that was greater than both bovine tail/calf lumbar spines (p<.001). There was no correlation between disc height and failure load within each individual species (p>.05). Cross sectional area and failure load did not correlate with failure load for human lumbar spine and bovine tails (p>.05) but did correlate with calf spine (r=0.53, p=.04). There was a statistically significant inverse correlation between disc height and Pfirrmann classification for human lumbar spines (r=-0.84, p<.001). There was also a statistically significant inverse relationship between Pfirrmann classification and failure load (r=-0.58, p=.02). CONCLUSIONS We have established a model for disc herniation and have shown how results of this model vary between species, disc morphology, and Pfirrmann classification. Both hypotheses were accepted: The force required for disc herniation was variable across species, and the force to herniation for human spines was inversely correlated with the degree of disc degeneration. We recommend that models using human intervertebral discs should include data on Pfirrmann classification, while biomechanical models using calf spines should report cross sectional area. Failure loads do not vary based on dimensions for bovine tails. CLINICAL SIGNIFICANCE Our analysis of models for disc herniation will allow for quicker, reliable comparisons of failure forces required to induce a disc herniation. Future work with these models may facilitate rapid testing of devices to repair a torn/ruptured annulus.
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DiStefano TJ, Shmukler JO, Danias G, Iatridis JC. The Functional Role of Interface Tissue Engineering in Annulus Fibrosus Repair: Bridging Mechanisms of Hydrogel Integration with Regenerative Outcomes. ACS Biomater Sci Eng 2020; 6:6556-6586. [PMID: 33320618 PMCID: PMC7809646 DOI: 10.1021/acsbiomaterials.0c01320] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hydrogels are extraordinarily versatile by design and can enhance repair in diseased and injured musculoskeletal tissues. Biological fixation of these constructs is a significant determinant factor that is critical to the clinical success and functionality of regenerative technologies for musculoskeletal repair. In the context of an intervertebral disc (IVD) herniation, nucleus pulposus tissue protrudes through the ruptured annulus fibrosus (AF), consequentially impinging on spinal nerve roots and causing debilitating pain. Discectomy is the surgical standard of care to treat symptomatic herniation; however these procedures do not repair AF defects, and these lesions are a significant risk factor for recurrent herniation. Advances in tissue engineering utilize adhesive hydrogels as AF sealants; however these repair strategies have yet to progress beyond preclinical animal models because these biomaterials are often plagued by poor integration with AF tissue and lead to large variability in repair outcomes. These critical barriers to translation motivate this article to review the material composition of hydrogels that have been evaluated in situ for AF repair, proposed mechanisms of how these biomaterials interface with AF tissue, and their functional outcomes after treatment in order to inform the development of new hydrogels for AF repair. In this systematic review, we identify 18 hydrogel formulations evaluated for AF repair, all of which demonstrate large heterogeneity in their interfacing mechanisms and reported outcome measures to assess the effectiveness of repair. Hydrogels that covalently bond to AF tissue were found to be the most successful in improving IVD biomechanical properties from the injured state, but none were able to restore properties to the intact state suggesting that new repair strategies with innovative surface chemistries are an important future direction. We additionally review biomechanical evaluation methods and recommend standardization in the field of AF tissue engineering to establish mechanical benchmarks for translation and ensure clinical feasibility.
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Affiliation(s)
- Tyler J DiStefano
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - Jennifer O Shmukler
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - George Danias
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - James C Iatridis
- Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
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15
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Ge J, Wang Y, Yan Q, Wu C, Yu H, Yang H, Zou J. FK506 Induces the TGF-β1/Smad 3 Pathway Independently of Calcineurin Inhibition to Prevent Intervertebral Disk Degeneration. Front Cell Dev Biol 2020; 8:608308. [PMID: 33363168 PMCID: PMC7758291 DOI: 10.3389/fcell.2020.608308] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 11/23/2020] [Indexed: 01/07/2023] Open
Abstract
Background Intervertebral disk (IVD) degeneration is the most common cause of lower back pain. Inhibiting inflammation is a key strategy for delaying IVD degeneration. Tacrolimus (FK506) is a potent immunosuppressive agent that is also beneficial to chondrocytes via alleviating inflammation. However, the potential function of FK506 in IVD and the underlying mechanisms remain unknown. The current study is aim at exploring the underlying mechanism of FK506 in preventing IVD degeneration. Methods Cell morphology was imaged using an optical microscope. mRNA levels of nucleus pulposus (NP) matrix components were determined by qRT-PCR, and protein expression NP matrix components was assessed by western blotting. A rat caudal IVD degeneration model was established to test for FK506 in vivo. Results FK506 improved the morphology of NP cells and the cell function at both the mRNA and protein level. FK506 could attenuate NP degeneration induced by IL-1β. Furthermore, FK506 exerted its function via TGFβ/Smad3 activation instead of through calcineurin inhibition. Inhibition of the TGF-β pathway prevented the protective effect of FK506 on IVD degeneration. In an in vivo study, FK506 injection reversed the development of rat caudal IVD degeneration influenced by Smad3. Conclusion Our current study demonstrates the positive effect of FK506 on delaying the degeneration of IVD via the TGFβ/Smad3 pathway.
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Affiliation(s)
- Jun Ge
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yingjie Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Qi Yan
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Cenhao Wu
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Hao Yu
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Huilin Yang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jun Zou
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
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16
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Alexeev D, Cui S, Grad S, Li Z, Ferguson SJ. Mechanical and biological characterization of a composite annulus fibrosus repair strategy in an endplate delamination model. JOR Spine 2020; 3:e1107. [PMID: 33392447 PMCID: PMC7770194 DOI: 10.1002/jsp2.1107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/08/2020] [Accepted: 06/21/2020] [Indexed: 12/23/2022] Open
Abstract
This study compares the mechanical response of the commonly used annulus fibrosus (AF) puncture injury model of the intervertebral disc (IVD) and a newly proposed AF failure at the endplate junction (delamination) on ex vivo bovine IVDs. Biocompatibility and mechanics of a newly developed repair strategy comprising of electrospun polycaprolactone (PCL) scaffold and fibrin-genipin (FibGen) adhesive was tested on the delamination model. The study found no significant difference in the mechanical response to compressive loading between the two models. Primary goals of the repair strategy to create a tight seal on the damage area and restore mechanical properties, while showing minimal cytotoxicity, were broadly achieved. Postrepair, the IVDs showed a significant restoration of mechanical properties compared to the injured samples for the delamination model. The FibGen glue showed a limited toxicity in the AF and produced a resilient and mechanically stable seal on the damaged area.
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Affiliation(s)
| | - Shangbin Cui
- AO Research Institute DavosDavosSwitzerland
- The First Affiliated Hospital, Sun Yat‐sen UniversityGuangzhouChina
| | - Sibylle Grad
- ETH Zürich, Institute for BiomechanicsZürichSwitzerland
- AO Research Institute DavosDavosSwitzerland
| | - Zhen Li
- AO Research Institute DavosDavosSwitzerland
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17
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Mern DS, Walsen T, Beierfuß A, Thomé C. Animal models of regenerative medicine for biological treatment approaches of degenerative disc diseases. Exp Biol Med (Maywood) 2020; 246:483-512. [PMID: 33175609 DOI: 10.1177/1535370220969123] [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: 12/14/2022] Open
Abstract
Degenerative disc disease (DDD) is a painful, chronic and progressive disease, which is characterized by inflammation, structural and biological deterioration of the intervertebral disc (IVD) tissues. DDD is specified as cell-, age-, and genetic-dependent degenerative process that can be accelerated by environmental factors. It is one of the major causes of chronic back pain and disability affecting millions of people globally. Current treatment options, such as physical rehabilitation, pain management, and surgical intervention, can provide only temporary pain relief. Different animal models have been used to study the process of IVD degeneration and develop therapeutic options that may restore the structure and function of degenerative discs. Several research works have depicted considerable progress in understanding the biological basis of disc degeneration and the therapeutic potentials of cell transplantation, gene therapy, applications of supporting biomaterials and bioactive factors, or a combination thereof. Since animal models play increasingly significant roles in treatment approaches of DDD, we conducted an electronic database search on Medline through June 2020 to identify, compare, and discuss publications regarding biological therapeutic approaches of DDD that based on intradiscal treatment strategies. We provide an up-to-date overview of biological treatment strategies in animal models including mouse, rat, rabbit, porcine, bovine, ovine, caprine, canine, and primate models. Although no animal model could profoundly reproduce the clinical conditions in humans; animal models have played important roles in specifying our knowledge about the pathophysiology of DDD. They are crucial for developing new therapy approaches for clinical applications.
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Affiliation(s)
| | - Tanja Walsen
- Department of Neurosurgery, Medical University of Innsbruck, Innsbruck A-6020, Austria
| | - Anja Beierfuß
- Laboratory Animal Facility, Medical University of Innsbruck, Innsbruck A-6020, Austria
| | - Claudius Thomé
- Department of Neurosurgery, Medical University of Innsbruck, Innsbruck A-6020, Austria
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18
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Fujii K, Lai A, Korda N, Hom WW, Evashwick-Rogler TW, Nasser P, Hecht AC, Iatridis JC. Ex-vivo biomechanics of repaired rat intervertebral discs using genipin crosslinked fibrin adhesive hydrogel. J Biomech 2020; 113:110100. [PMID: 33142205 DOI: 10.1016/j.jbiomech.2020.110100] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 09/02/2020] [Accepted: 10/17/2020] [Indexed: 12/14/2022]
Abstract
Microdiscectomy is the current standard surgical treatment for intervertebral disc (IVD) herniation, however annulus fibrosus (AF) defects remain unrepaired which can alter IVD biomechanical properties and lead to reherniation, IVD degeneration and recurrent back pain. Genipin-crosslinked fibrin (FibGen) hydrogel is an injectable AF sealant previously shown to partially restore IVD motion segment biomechanical properties. A small animal model of herniation and repair is needed to evaluate repair potential for early-stage screening of IVD repair strategies prior to more costly large animal and eventual human studies. This study developed an ex-vivo rat caudal IVD herniation model and characterized torsional, axial tension-compression and stress relaxation biomechanical properties before and after herniation injury with or without repair using FibGen. Injury group involved an annular defect followed by removal of nucleus pulposus tissue to simulate a severe herniation while Repaired group involved FibGen injection. Injury significantly altered axial range of motion, neutral zone, torsional stiffness, torque range and stress-relaxation biomechanical parameters compared to Intact. FibGen repair restored the stress-relaxation parameters including effective hydraulic permeability indicating it effectively sealed the IVD defect, and there was a trend for improved tensile stiffness and axial neutral zone length. This study demonstrated a model for studying IVD herniation injury and repair strategies using rat caudal IVDs ex-vivo and demonstrated FibGen sealed IVDs to restore water retention and IVD pressurization. This ex-vivo small animal model may be modified for future in-vivo studies to screen IVD repair strategies using FibGen and other IVD repair biomaterials as an augment to additional large animal and human IVD testing.
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Affiliation(s)
- Kengo Fujii
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States; Department of Orthopaedic Surgery, University of Tsukuba, Tsukuba, Japan
| | - Alon Lai
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Nimrod Korda
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Warren W Hom
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Thomas W Evashwick-Rogler
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States; University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Philip Nasser
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Andrew C Hecht
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - James C Iatridis
- Leni & Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
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19
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Ge J, Cheng X, Yan Q, Wu C, Wang Y, Yu H, Yang H, Zhou F, Zou J. Calcitonin inhibits intervertebral disc degeneration by regulating protein kinase C. J Cell Mol Med 2020; 24:8650-8661. [PMID: 32564456 PMCID: PMC7412402 DOI: 10.1111/jcmm.15496] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 04/29/2020] [Accepted: 05/24/2020] [Indexed: 01/18/2023] Open
Abstract
Intervertebral disc degeneration (IVDD) is the most critical factor that causes low back pain. Molecular biotherapy is a fundamental strategy for IVDD treatment. Calcitonin can promote the proliferation of chondrocytes, stimulate the synthesis of matrix and prevent cartilage degeneration. However, its effect and the underlying mechanism for IVDD have not been fully revealed. Chondrogenic specific matrix components’ mRNA expression of nucleus pulposus cell (NPC) was determined by qPCR. Protein expression of NPC matrix components and protein kinase C was determined by Western blotting. A rat caudal intervertebral disc degeneration model was established and tested for calcitonin in vivo. IL‐1 induced NPC change via decreasing protein kinase C (PKC)‐ε phosphorylation, while increasing PKC‐δ phosphorylation. Calcitonin treatment could prevent or reverse IL‐1‐induced cellular change on PKC signalling associated with degeneration. The positive effect of calcitonin on IVDD in vivo was verified on a rat caudal model. In summary, this study, for the first time, elucidated the important role of calcitonin in the regulation of matrix components in the nucleus of the intervertebral disc. Calcitonin can delay degeneration of the intervertebral disc nucleus by activating the PKC‐ε pathway and inhibiting the PKC‐δ pathway.
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Affiliation(s)
- Jun Ge
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Xiaoqiang Cheng
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Qi Yan
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Cenhao Wu
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yingjie Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Hao Yu
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Huilin Yang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Feng Zhou
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jun Zou
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, China
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Hussain I, Sloan SR, Wipplinger C, Navarro-Ramirez R, Zubkov M, Kim E, Kirnaz S, Bonassar LJ, Härtl R. Mesenchymal Stem Cell-Seeded High-Density Collagen Gel for Annular Repair: 6-Week Results From In Vivo Sheep Models. Neurosurgery 2020; 85:E350-E359. [PMID: 30476218 DOI: 10.1093/neuros/nyy523] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 10/04/2018] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Our group has previously demonstrated in vivo annulus fibrosus repair in animal models using an acellular, riboflavin crosslinked, high-density collagen (HDC) gel. OBJECTIVE To assess if seeding allogenic mesenchymal stem cells (MSCs) into this gel yields improved histological and radiographic benefits in an in vivo sheep model of annular injury. METHODS Fifteen lumbar intervertebral discs (IVDs) were randomized into 4 groups: intact, injury only, injury + acellular gel treatment, or injury + MSC-seeded gel treatment. Sheep were sacrificed at 6 wk. Disc height index (DHI), Pfirrmann grade, nucleus pulposus area, and T2 relaxation time (T2-RT) were calculated for each IVD and standardized to healthy controls from the same sheep. Quantitative histological assessment was also performed using the Han scoring system. RESULTS All treated IVDs retained gel plugs on gross assessment and there were no adverse perioperative complications. The MSC-seeded gel treatment group demonstrated statistically significant improvement over other experimental groups in DHI (P = .002), Pfirrmann grade (P < .001), and T2-RT (P = .015). There was a trend for greater Han scores in the MSC-seeded gel-treated discs compared with injury only and acellular gel-treated IVDs (P = .246). CONCLUSION MSC-seeded HDC gel can be delivered into injured IVDs and maintained safely in live sheep to 6 wk. Compared with no treatment and acellular HDC gel, our data show that MSC-seeded HDC gel improves outcomes in DHI, Pfirrmann grade, and T2-RT. Histological analysis shows improved annulus fibrosus and nucleus pulposus reconstitution and organization over other experimental groups as well.
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Affiliation(s)
- Ibrahim Hussain
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
| | - Stephen R Sloan
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York
| | - Christoph Wipplinger
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
| | - Rodrigo Navarro-Ramirez
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
| | - Micaella Zubkov
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
| | - Eliana Kim
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
| | - Sertac Kirnaz
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York.,Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York
| | - Roger Härtl
- Department of Neurological Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, New York
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21
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Jiang EY, Sloan SR, Wipplinger C, Kirnaz S, Härtl R, Bonassar LJ. Proteoglycan removal by chondroitinase ABC improves injectable collagen gel adhesion to annulus fibrosus. Acta Biomater 2019; 97:428-436. [PMID: 31425894 DOI: 10.1016/j.actbio.2019.08.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/24/2019] [Accepted: 08/13/2019] [Indexed: 12/14/2022]
Abstract
Intervertebral disc (IVD) herniations are currently treated with interventions that leave the IVD with persistent lesions prone to further herniations. Annulus fibrosus (AF) repair has become of interest as a method to seal defects in the IVD and prevent reherniation, but this requires strong adhesion of the implanted biomaterial to the native AF tissue. Our group has previously developed a high-density collagen (HDC) gel for AF repair and tested its efficacy in vivo, but its adhesion to the AF could be improved. Increased cell adhesion to cartilage has previously been reported through chondroitinase ABC (ChABC) digestion, which removes proteoglycans and increases access to cell binding motifs. Such approaches could also increase biomaterial adhesion to tissue, but the effects of ChABC digestion on AF have yet to be investigated. In this study, ovine AF tissue was digested with either 10 U/mL ChABC or saline for up to 10 min and the effect of this treatment on collagen adhesion between AF tissue samples was investigated by histology and mechanical testing in a lap-shear configuration. ChABC digestion removed proteoglycans within the AF in a time-dependent fashion and enhanced adhesion of the HDC gel to the AF. ChABC digestion increased the elastic toughness and total shear energy of the HDC gel-AF interface by 88% and 46% respectively. ChABC treatment enhanced the adhesion of the HDC gel to the AF without significantly decreasing native AF cell viability. Thus, ChABC digestion is a viable method to improve adhesion of biomaterials for AF repair. STATEMENT OF SIGNIFICANCE: Intervertebral disc herniations are currently treated with interventions that leave persistent lesions in the annulus fibrosus that are prone to further herniations. Annular repair is a promising method to seal lesions and prevent reherniation, but requires strong adhesion of the implanted biomaterial to native annulus fibrosus. Since large proteoglycans like aggrecan occupy regions of the extracellular matrix between collagen fibers in the annulus fibrosus, we hypothesized that removing proteoglycans via chondroitinase digestion would increase the adhesion of annular repair hydrogels. This investigation demonstrated that chondroitinase removed proteoglycans within annulus fibrosus tissue, enhanced the interaction of an injected collagen gel with the native tissue, and mechanically improved adhesion between the collagen gel and annulus fibrosus. This is the first study of its kind to evaluate the biochemical and mechanical effects of short-term chondroitinase digestion on annulus fibrosus tissue.
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22
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Du ZC, Zhu LX. A Heterologous Fibrin Glue Enhances the Closure Effect of Surgical Suture on the Repair of Annulus Fibrous Defect in a Sheep Model. Curr Med Sci 2019; 39:597-603. [PMID: 31346996 DOI: 10.1007/s11596-019-2079-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 03/25/2019] [Indexed: 12/20/2022]
Abstract
Improving the closure effect of surgical suture for repair of annulus fibrosus defects remains an unsolved problem. A new type of porcine fibrin glue was reported for the repair of annulus fibrous defects in sheep models in this study. Continuous axial loading test showed that this glue could effectively improve the closure effect of surgical suture for annulus fibrous defect. Magnetic resonance imaging (MRI) of the lumbar spine confirmed that, compared with non-fibrin glue treated intervertebral discs, it contributed to preservation of the nucleus pulposus and maintained the physiological hydration of the intervertebral discs. Moreover, histomorphology evaluation showed that the porcine fibrin glue could partially reverse degeneration of the injured intervertebral discs. Taken together, porcine fibrin glue can effectively enhance the closure effect of surgical suture on annulus fibrosus, improve the repair effect and slow down the degeneration of the intervertebral disc, and provide a potential therapeutic strategy for degenerative intervertebral disc disease.
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Affiliation(s)
- Zhi-Cai Du
- Southern Medical University, Guangzhou, 510515, China.,Department of Minimally Invasive Spinal Surgery, the Second Affiliated Hospital of Inner Mongolia Medical University, Hohhot, 010030, China
| | - Li-Xin Zhu
- Southern Medical University, Guangzhou, 510515, China. .,Department of Orthopaedic Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China.
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23
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Nukaga T, Sakai D, Schol J, Sato M, Watanabe M. Annulus fibrosus cell sheets limit disc degeneration in a rat annulus fibrosus injury model. JOR Spine 2019; 2:e1050. [PMID: 31463464 PMCID: PMC6686811 DOI: 10.1002/jsp2.1050] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/18/2019] [Accepted: 05/11/2019] [Indexed: 12/11/2022] Open
Abstract
In recent years, studies have explored novel approaches for cell transplantation to enable annulus fibrosus (AF) regeneration of the intervertebral disc in particular for lumbar disc herniation. Nevertheless, successful engraftment of cells is structurally challenging, and no definitive method has yet been established. This study investigated the potential of cell sheet technology to facilitate cell engraftment for AF repair. AF injury was induced by a 1 × 1 mm defect in rat tails after which AF cell sheets were transplanted. Its regenerative effects were compared to a nondegenerated and degeneration only conditions. Degenerative changes of the entire intervertebral disc were examined by disc height measurements, histology, and immunohistochemistry for 4-, 8-, and 12-weeks post-transplantation. Cell engraftment was confirmed by tracing PKH26 fluorescent dyed AF cells. In the transplant group, disc degeneration was significantly suppressed after 4, 8, and 12 weeks when compared with the degenerative group, as indicated by histological scoring and DHI observations. At 2 and 4 weeks after transplant, PKH26 positive cells could be detected in defect region and surrounding AF. The results suggest cell engraftment into AF tissue could be established by the cell sheet technology without additional scaffolding or adhesives. In short, AF cell sheets appear to be an effective and accessible tool for AF repair and to support intervertebral disc regeneration.
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Affiliation(s)
- Tadashi Nukaga
- Department of Orthopaedic SurgeryTokai University School of MedicineIseharaKanagawaJapan
| | - Daisuke Sakai
- Department of Orthopaedic SurgeryTokai University School of MedicineIseharaKanagawaJapan
| | - Jordy Schol
- Department of Orthopaedic SurgeryTokai University School of MedicineIseharaKanagawaJapan
| | - Masato Sato
- Department of Orthopaedic SurgeryTokai University School of MedicineIseharaKanagawaJapan
| | - Masahiko Watanabe
- Department of Orthopaedic SurgeryTokai University School of MedicineIseharaKanagawaJapan
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24
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Tissue Engineering Strategies for Intervertebral Disc Treatment Using Functional Polymers. Polymers (Basel) 2019; 11:polym11050872. [PMID: 31086085 PMCID: PMC6572548 DOI: 10.3390/polym11050872] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 04/24/2019] [Accepted: 05/02/2019] [Indexed: 02/07/2023] Open
Abstract
Intervertebral disc (IVD) is the fibrocartilage between the vertebrae, allowing the spine to move steadily by bearing multidirectional complex loads. Aging or injury usually causes degeneration of IVD, which is one of the main reasons for low back pain prevalent worldwide and reduced quality of life. While various treatment strategies for degenerative IVD have been studied using in vitro studies, animal experiments, and clinical trials, there are unsolved limitations for endogenous regeneration of degenerative IVD. In this respect, several tissue engineering strategies that are based on the cell and scaffolds have been extensively researched with positive outcomes for regeneration of IVD tissues. Scaffolds made of functional polymers and their diverse forms mimicking the macro- and micro-structure of native IVD enhance the biological and mechanical properties of the scaffolds for IVD regeneration. In this review, we discuss diverse morphological and functional polymers and tissue engineering strategies for endogenous regeneration of degenerative IVD. Tissue engineering strategies using functional polymers are promising therapeutics for fundamental and endogenous regeneration of degenerative IVD.
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25
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Biomechanical test protocols to detect minor injury effects in intervertebral discs. J Mech Behav Biomed Mater 2019; 95:13-20. [PMID: 30947120 DOI: 10.1016/j.jmbbm.2019.03.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/26/2019] [Accepted: 03/22/2019] [Indexed: 01/21/2023]
Abstract
Intervertebral discs (IVDs) maintain flexibility of the spine and bear mechanical load. Annulus fibrosus (AF) defects are associated with IVD degeneration and herniation which disrupt biomechanical function and can cause pain. AF puncture injuries can induce IVD degeneration but are needed to inject therapies. Identifying small AF defects with biomechanical testing can be difficult because IVDs have a complex, composite structure and nonlinear biomechanical properties that are dependent on AF fiber tension. It remains unclear how choice of biomechanical testing protocols affect the sensitivity of biomechanical properties to AF injuries. This study determined whether axial preload or magnitude of cyclic axial or torsional testing affected the ability to detect minor AF defects in rat caudal motion segments using ex vivo biomechanical testing. Intact and injured motion segments were subjected to a repeated measures study design with multiple biomechanical testing protocols that varied axial tension-compression force amplitude (±1.6 N, ±8.0 N, ±16.0 N), axial preload (-1.6 N, -8.0 N, -16.0 N, corresponding to -0.1 MPa, -0.5 MPa, and -1.0 MPa, respectively), and torsional rotation angle (±10°, ±15°, and ±20°). Biomechanical properties obtained from the lowest force testing conditions for axial tension-compression (±1.6 N), axial preload (-1.6 N), and angular rotation (±10°) exhibited the largest differences in biomechanical properties between intact and injured conditions. Biomechanical properties determined under low axial force or torsion amplitudes involve less AF fiber tension and were most sensitive to injury. Low force testing protocols are recommended for detecting minor structural AF defects and may enable more precise assessments of IVD injuries, healing or repair.
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26
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Moriguchi Y, Borde B, Berlin C, Wipplinger C, Sloan SR, Kirnaz S, Pennicooke B, Navarro-Ramirez R, Khair T, Grunert P, Kim E, Bonassar L, Härtl R. In vivo annular repair using high-density collagen gel seeded with annulus fibrosus cells. Acta Biomater 2018; 79:230-238. [PMID: 29981494 DOI: 10.1016/j.actbio.2018.07.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 05/25/2018] [Accepted: 07/03/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The aim is assessing the in vivo efficacy of annulus fibrosus (AF) cells seeded into collagen by enhancing the reparative process around annular defects and preventing further degeneration in a rat-tail model. SUMMARY OF BACKGROUND DATA Treating disc herniation with discectomy may relieve the related symptoms but does not address the underlying pathology. The persistent annular defect may lead to re-herniation and further degeneration. We recently demonstrated that riboflavin crosslinked high-density collagen gels (HDC) can facilitate annular repair in vivo. METHODS 42 rats, tail disc punctured with an 18-gauge needle, were divided into 3 groups: untreated (n = 6), injected with crosslinked HDC (n = 18), and injected with AF cell-laden crosslinked HDC (n = 18). Ovine AF cells were mixed with HDC gels prior to injection. X-rays and MRIs were conducted over 5 weeks, determining disc height index (DHI), nucleus pulposus (NP) size, and hydration. Histological assessments evaluated the viability of implanted cells and degree of annular repair. RESULTS Although average DHIs of both HDC gel groups were higher than those of the puncture control group at 5 weeks, the retention of disc height, NP size and hydration at 1 and 5 weeks was significant for the cellular group compared to the punctured, and at 5 weeks to the acellular group. Histological assessment indicated that AF cell-laden HDC gels have accelerated reparative sealing compared to acellular HDC gels. CONCLUSIONS AF cell-laden HDC gels have the ability of better repairing annular defects than acellular gels after needle puncture. STATEMENT OF SIGNIFICANCE This project addresses the compelling demand of a sufficient treatment strategy for degenerative disc disease (DDD) perpetuated by annulus fibrosus (AF) injury, a major cause of morbidity and burden to health care systems. Our study is designed to answer the question of whether injectable, photo-crosslinked, high density collagen gels can seal defects in the annulus fibrosus of rats and prevent disc degeneration. Furthermore, we investigated whether the healing of AF defects will be enhanced by the delivery of AF cells (fibrochondrocytes) to these defects. The use of cell-laden collagen gels in spine surgery holds promise for a wide array of applications, from current discectomy procedures to future nucleus pulposus reparative therapies, and our group is excited about this potential.
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27
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D'Este M, Eglin D, Alini M. Lessons to be learned and future directions for intervertebral disc biomaterials. Acta Biomater 2018; 78:13-22. [PMID: 30092378 DOI: 10.1016/j.actbio.2018.08.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 07/16/2018] [Accepted: 08/04/2018] [Indexed: 02/07/2023]
Abstract
Biomaterials science has achieved significant advancements for the replacement, repair and regeneration of intervertebral disc tissues. However, the translation of this research to the clinic presents hurdles. The goal of this paper is to identify strategies to recapitulate the intrinsic complexities of the intervertebral disc, to highlight the unresolved issues in basic knowledge hindering the clinical translation, and finally to report on the emerging technologies in the biomaterials field. On this basis, we identify promising research directions, with the hope of stimulating further debate and advances for resolving clinical problems such as cervical and low back pain using biomaterial-based approaches. STATEMENT OF SIGNIFICANCE Although not life-threatening, intervertebral disc disorders have enormous impact on life quality and disability. Disc function within the human body is mainly mechanical, and therefore the use of biomaterials to rescue disc function and alleviate pain is logical. Despite intensive research, the clinical translation of biomaterial-based therapies is hampered by the intrinsic complexity of this organ. After decades of development, artificial discs or tissue replacements are still niche applications given their issues of integration and displacement with detrimental consequences. The struggles of biological therapies and tissue engineering are therefore understandable. However, recent advances in biomaterial science give new hope. In this paper we identify the most promising new directions for intervertebral disc biomaterials.
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28
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Huang YC, Hu Y, Li Z, Luk KDK. Biomaterials for intervertebral disc regeneration: Current status and looming challenges. J Tissue Eng Regen Med 2018; 12:2188-2202. [PMID: 30095863 DOI: 10.1002/term.2750] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 05/21/2018] [Accepted: 07/13/2018] [Indexed: 12/19/2022]
Abstract
A biomaterial-based strategy is employed to regenerate the degenerated intervertebral disc, which is considered a major generator of neck and back pain. Although encouraging enhancements in the anatomy and kinematics of the degenerative disc have been gained by biomaterials with various formulations in animals, the number of biomaterials tested in humans is rare. At present, most studies that involve the use of newly developed biomaterials focus on regeneration of the degenerative disc, but not pain relief. In this review, we summarise the current state of the art in the field of biomaterial-based regeneration or repair for the nucleus pulposus, annulus fibrosus, and total disc transplantation in animals and humans, and we then provide essential suggestions for the development and clinical translation of biomaterials for disc regeneration. It is important for researchers to consider the commonly neglected issues instead of concentrating solely on biomaterial development and fabrication.
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Affiliation(s)
- Yong-Can Huang
- Shenzhen Engineering Laboratory of Orthopaedic Regenerative Technologies, Orthopaedic Research Center, Peking University Shenzhen Hospital, Shenzhen, China.,Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China.,Shenzhen Key Laboratory of Spine Surgery, Department of Spine Surgery, Peking University Shenzhen Hospital, Shenzhen, China
| | - Yong Hu
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China
| | - Zhen Li
- AO Research Institute Davos, Davos, Switzerland
| | - Keith D K Luk
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China
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29
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Abstract
STUDY DESIGN Ovine in vivo study. OBJECTIVE To perform lateral approach lumbar surgery in an ovine model to administer an injectable riboflavin cross-linked high-density collagen (HDC) gel and to assess its ability to mitigate intervertebral disc (IVD) degeneration after induced annulus fibrosus (AF) injury. SUMMARY OF BACKGROUND DATA Biological-based injectable gels have shown efficacy in restoring biomechanical, radiographic, and histological parameters in IVD-injured animal models. Riboflavin cross-linked HDC gel has previously demonstrated retention of nucleus pulposus (NP) tissue, reduced loss of disc height, and prevention of terminal cellular degenerative changes in rat-tail spines. However, this biological therapy has never been tested in large animal models. METHODS Forty lumbar IVDs were accessed from eight sheep via lateral approach surgery. IVDs were randomly assigned to healthy control, injury and HDC treatment, or negative control with injury and no treatment. IVD injury was carried out using a drill-bit through the AF followed by needle puncture of the NP. Sheep were followed for 16 weeks and underwent qualitative/quantitative magnetic resonance imaging, x-ray, and histological analyses of collagen and proteoglycan content. RESULTS The lateral approach to the ovine lumbar spine to deliver HDC gel proved to be safe and reproducible. IVDs treated with the HDC gel revealed less degenerative changes at the microscopic level based on AF and NP histology. However, mean Pfirrmann grade, T2 relaxation time, NP voxel size, and disc height index were not significantly different between the two injury groups. CONCLUSION Injectable HDC gel can be administered safely via lateral approach surgery in an ovine AF injury model. IVDs treated with HDC gel demonstrated less degeneration at the microscopic level though radiographic changes were slight when comparing treated to untreated IVDs. Future studies will need to elucidate the role of injury technique and time frame for follow-up in correlating histological and radiographical outcomes. LEVEL OF EVIDENCE N /A.
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30
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Sloan SR, Lintz M, Hussain I, Hartl R, Bonassar LJ. Biologic Annulus Fibrosus Repair: A Review of Preclinical In Vivo Investigations. TISSUE ENGINEERING PART B-REVIEWS 2018; 24:179-190. [PMID: 29105592 DOI: 10.1089/ten.teb.2017.0351] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Lower back pain, the leading cause of workplace absences and disability, is often attributed to intervertebral disc degeneration, in which nucleus pulposus (NP) herniates through lesions in the annulus fibrosus (AF) and impinges on the spinal cord and surrounding nerves. Surgeons remove extruded NP via discectomy when indicated by local/radicular pain supported by radiographic evidence; however, current interventions do not alter the underlying disease or seal the AF. The reported rates of recurrent herniation or pain following discectomy cases range from 5% to 25%, which has pushed spine research in recent years toward annular repair and closure strategies. Synthetic implants designed to mechanically seal the AF have been subject to large animal and clinical trials, with limited success in preventing recurrent herniation. Like gold standard interventions, purely mechanical devices fail to promote tissue integration, long-term healing, or restore native biomechanical function to the spine. Biological repair strategies utilizing principles of tissue engineering have demonstrated success in overcoming the inadequacies of current interventions and mechanical implants, yet, none has reached clinical or proof-of-concept trials in humans. In this review, we will discuss annular repair strategies promoting biological healing that have been implemented in small and large animal models in vivo, and ways to enhance the efficacy of these treatments.
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Affiliation(s)
- Stephen R Sloan
- 1 Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York
| | - Marianne Lintz
- 1 Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York
| | - Ibrahim Hussain
- 2 Department of Neurological Surgery, Weill Cornell Brain and Spine Center , New York-Presbyterian Hospital, New York, New York
| | - Roger Hartl
- 2 Department of Neurological Surgery, Weill Cornell Brain and Spine Center , New York-Presbyterian Hospital, New York, New York
| | - Lawrence J Bonassar
- 1 Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York.,3 Sibley School of Mechanical and Aerospace Engineering, Cornell University , Ithaca, New York
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31
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Lin X, Fang X, Wang Q, Hu Z, Chen K, Shan Z, Chen S, Wang J, Mo J, Ma J, Xu W, Qin A, Fan S. Decellularized allogeneic intervertebral disc: natural biomaterials for regenerating disc degeneration. Oncotarget 2017; 7:12121-36. [PMID: 26933821 PMCID: PMC4914273 DOI: 10.18632/oncotarget.7735] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 02/18/2016] [Indexed: 12/19/2022] Open
Abstract
Intervertebral disc degeneration is associated with back pain and disc herniation. This study established a modified protocol for intervertebral disc (IVD) decellularization and prepared its extracellular matrix (ECM). By culturing mesenchymal stem cells (MSCs)(3, 7, 14 and 21 days) and human degenerative IVD cells (7 days) in the ECM, implanting it subcutaneously in rabbit and injecting ECM microparticles into degenerative disc, the biological safety and efficacy of decellularized IVD was evaluated both in vitro and in vivo. Here, we demonstrated that cellular components can be removed completely after decellularization and maximally retain the structure and biomechanics of native IVD. We revealed that allogeneic ECM did not evoke any apparent inflammatory reaction in vivo and no cytotoxicity was found in vitro. Moreover, IVD ECM can induce differentiation of MSCs into IVD-like cells in vitro. Furthermore, allogeneic ECM microparticles are effective on the treatment of rabbit disc degeneration in vivo. In conclusion, our study developed an optimized method for IVD decellularization and we proved decellularized IVD is safe and effective for the treatment of degenerated disc diseases.
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Affiliation(s)
- Xianfeng Lin
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Xiangqian Fang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Qiang Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Zhijun Hu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Kai Chen
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Wenzhou Medical College, Wenzhou, China
| | - Zhi Shan
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China
| | - Shuai Chen
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Jiying Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Jian Mo
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Jianjun Ma
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - Wenbing Xu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
| | - An Qin
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedic Implant, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Shunwu Fan
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Micro-Invasive Surgery of Zhejiang University, Hangzhou, China
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32
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Moriguchi Y, Mojica-Santiago J, Grunert P, Pennicooke B, Berlin C, Khair T, Navarro-Ramirez R, Ricart Arbona RJ, Nguyen J, Härtl R, Bonassar LJ. Total disc replacement using tissue-engineered intervertebral discs in the canine cervical spine. PLoS One 2017; 12:e0185716. [PMID: 29053719 PMCID: PMC5650136 DOI: 10.1371/journal.pone.0185716] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/18/2017] [Indexed: 01/07/2023] Open
Abstract
The most common reason that adults in the United States see their physician is lower back or neck pain secondary to degenerative disc disease. To date, approaches to treat degenerative disc disease are confined to purely mechanical devices designed to either eliminate or enable flexibility of the diseased motion segment. Tissue engineered intervertebral discs (TE-IVDs) have been proposed as an alternative approach and have shown promise in replacing native IVD in the rodent tail spine. Here we demonstrate the efficacy of our TE-IVDs in the canine cervical spine. TE-IVD components were constructed using adult canine annulus fibrosis and nucleus pulposus cells seeded into collagen and alginate hydrogels, respectively. Seeded gels were formed into a single disc unit using molds designed from the geometry of the canine spine. Skeletally mature beagles underwent discectomy with whole IVD resection at levels between C3/4 and C6/7, and were then divided into two groups that received only discectomy or discectomy followed by implantation of TE-IVD. Stably implanted TE-IVDs demonstrated significant retention of disc height and physiological hydration compared to discectomy control. Both 4-week and 16-week histological assessments demonstrated chondrocytic cells surrounded by proteoglycan-rich matrices in the NP and by fibrocartilaginous matrices in the AF portions of implanted TE-IVDs. Integration into host tissue was confirmed over 16 weeks without any signs of immune reaction. Despite the significant biomechanical demands of the beagle cervical spine, our stably implanted TE-IVDs maintained their position, structure and hydration as well as disc height over 16 weeks in vivo.
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Affiliation(s)
- Yu Moriguchi
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Jorge Mojica-Santiago
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States of America
| | - Peter Grunert
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Brenton Pennicooke
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Connor Berlin
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Thamina Khair
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Rodrigo Navarro-Ramirez
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Rodolfo J. Ricart Arbona
- Center of Comparative Medicine and Pathology, Memorial Sloan Kettering Cancer Center & Weill Cornell Medicine, New York, NY, United States of America
| | - Joseph Nguyen
- Healthcare Research Institute, Hospital for Special Surgery, Hospital for Special Surgery, New York, NY, United States of America
| | - Roger Härtl
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Lawrence J. Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States of America
- * E-mail:
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Sloan SR, Galesso D, Secchieri C, Berlin C, Hartl R, Bonassar LJ. Initial investigation of individual and combined annulus fibrosus and nucleus pulposus repair ex vivo. Acta Biomater 2017; 59:192-199. [PMID: 28669721 DOI: 10.1016/j.actbio.2017.06.045] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 06/26/2017] [Accepted: 06/28/2017] [Indexed: 01/05/2023]
Abstract
Novel tissue engineered and biomaterial approaches to treat intervertebral disc (IVD) degeneration focus on single aspects of the progressive disease and hence are insufficient repair strategies. In this study, annulus fibrosus (AF) and nucleus pulposus (NP) biomaterial repair strategies were used individually and combined to treat IVD degeneration modeled in ex vivo rat-tail motion segments by annulotomy and nucleotomy. An injectable riboflavin cross-linked high-density collagen gel patched defects in the AF, while NP repair consisted of injections of a modified hyaluronic acid (HA) hydrogel. Qualitative imaging showed the annulotomy and nucleotomy successfully herniated NP material, while the HA NP injections restored intact NP morphology and the collagen AF patches sealed AF defects. Assessed by quantitative T2 magnetic resonance imaging, combined repair treatments yielded disc hydration not significantly different than intact hydration, while AF and NP repairs alone only restored ∼1/3 of intact hydration. Mechanical testing showed NP injections alone recovered on average ∼35% and ∼40% of the effective instantaneous and equilibrium moduli. The combined treatment comprising biomaterial AF and NP repair was effective at increasing NP hydration from NP repair alone, however HA injections alone are sufficient to improve mechanical properties. STATEMENT OF SIGNIFICANCE Intervertebral disc degeneration affects an estimated 90% of individuals throughout their life, and is a candidate pathology for tissue engineered repair. The current standard of clinical care reduces spinal articulation and leads to further degeneration along the spine, hence great interest in a regenerative medicine therapy. Literature studies focused on biomaterial repair strategies for treating degenerated discs have partially restored native disc function, however no studies have reported the use of combined therapies to address multiple aspects of disc degeneration. This initial investigation screened injectable biomaterial repair strategies ex vivo, and through complementary outcome measures showed a combined therapy restores disc function better than individual approaches. This study is the first of its kind to address multiple aspects of disc degeneration, using clinically-oriented biomaterials in a well-established animal model.
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The Quantitative Structural and Compositional Analyses of Degenerating Intervertebral Discs Using Magnetic Resonance Imaging and Contrast-Enhanced Micro-Computed Tomography. Ann Biomed Eng 2017; 45:2626-2634. [PMID: 28744842 DOI: 10.1007/s10439-017-1891-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 07/20/2017] [Indexed: 01/31/2023]
Abstract
The intervertebral disc (IVD) is susceptible to degenerative changes that are associated with low back pain. Murine models are often used to investigate the mechanistic changes in the development, aging, and diseased states of the IVD, yet the detection of early degenerative changes in structure is challenging because of the minute size of the murine IVDs. Histology is the gold standard for examining the IVD structure, but it is susceptible to sectioning artifacts, spatial biases, and requires the destructive preparation of the sample. We have previously demonstrated the feasibility of using Ioversol for the contrast-enhanced micro-computed tomography (microCT) to visualize and quantitate the intact healthy murine IVD. In this work, we demonstrate utility of this approach to monitor the longitudinal changes of in vitro nucleolytic- and mechanical injury- degeneration models of the murine discs and introduce novel quantitative metrics to characterize the structure and composition of the IVD. Moreover, we compared the imaging quality and quantitation of these in vitro models to magnetic resonance imaging (MRI) and histology. Stab puncture, trypsin injection, and collagenase injection all induced detectable and significant changes in structure and composition of the discs overtime. Compared to MRI and histology, contrast-enhanced microCT produced superior images that capture the degenerative progression in these models. Contrast-enhanced microCT was also capable of monitoring the structural deteriorations via the changes in disc height and volume, and novel the nucleus pulposus intensity/disc intensity (NI/DI) parameter provides a surrogate measure of proteoglycan composition (R = 0.96). Overall, this approach allows for the nondestructive monitoring of the structure and composition of the IVD at very high resolutions.
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Tavakoli J. Tissue Engineering of the Intervertebral Disc's Annulus Fibrosus: A Scaffold-Based Review Study. Tissue Eng Regen Med 2017; 14:81-91. [PMID: 30603465 PMCID: PMC6171584 DOI: 10.1007/s13770-017-0024-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 04/10/2016] [Accepted: 06/08/2016] [Indexed: 12/11/2022] Open
Abstract
Tissue engineering as a high technology solution for treating disc's problem has been the focus of some researches recently; however, the upcoming successful results in this area depends on understanding the complexities of biology and engineering interface. Whereas the major responsibility of the nucleus pulposus is to provide a sustainable hydrated environment within the disc, the function of the annulus fibrosus (AF) is more mechanical, facilitating joint mobility and preventing radial bulging by confining of the central part, which makes the AF reconstruction important. Although the body of knowledge regarding the AF tissue engineering has grown rapidly, the opportunities to improve current understanding of how artificial scaffolds are able to mimic the AF concentric structure-including inter-lamellar matrix and cross-bridges-addressed unresolved research questions. The aim of this literature review was to collect and discuss, from the international scientific literature, information about tissue engineering of the AF based on scaffold fabrication and material properties, useful for developing new strategies in disc tissue engineering. The key parameter of this research was understanding if role of cross-bridges and inter-lamellar matrix has been considered on tissue engineering of the AF.
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Affiliation(s)
- Javad Tavakoli
- Medical Device Research Institute, School of Computer Science, Engineering and Mathematics, Flinders University, Adelaide, SA 5042 Australia
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Bowles RD, Setton LA. Biomaterials for intervertebral disc regeneration and repair. Biomaterials 2017; 129:54-67. [PMID: 28324865 DOI: 10.1016/j.biomaterials.2017.03.013] [Citation(s) in RCA: 210] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 03/05/2017] [Accepted: 03/10/2017] [Indexed: 12/11/2022]
Abstract
The intervertebral disc contributes to motion, weight bearing, and flexibility of the spine, but is susceptible to damage and morphological changes that contribute to pathology with age and injury. Engineering strategies that rely upon synthetic materials or composite implants that do not interface with the biological components of the disc have not met with widespread use or desirable outcomes in the treatment of intervertebral disc pathology. Here we review bioengineering advances to treat disc disorders, using cell-supplemented materials, or acellular, biologically based materials, that provide opportunity for cell-material interactions and remodeling in the treatment of intervertebral disc disorders. While a field still in early development, bioengineering-based strategies employing novel biomaterials are emerging as promising alternatives for clinical treatment of intervertebral disc disorders.
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Affiliation(s)
- Robert D Bowles
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA.
| | - Lori A Setton
- Department of Biomedical Engineering & Orthopedic Surgery, Washington University in St. Louis, St. Louis, MO 63130, USA.
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Chuah YJ, Peck Y, Lau JEJ, Hee HT, Wang DA. Hydrogel based cartilaginous tissue regeneration: recent insights and technologies. Biomater Sci 2017; 5:613-631. [DOI: 10.1039/c6bm00863a] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Hydrogel based technologies has been extensively employed in both exploratory research and clinical applications to address numerous existing challenges in the regeneration of articular cartilage and intervertebral disc.
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Affiliation(s)
- Yon Jin Chuah
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
- Singapore
| | - Yvonne Peck
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
- Singapore
| | - Jia En Josias Lau
- School of Chemical & Life Sciences
- Singapore Polytechnic
- Singapore 139651
- Singapore
| | - Hwan Tak Hee
- Lee Kong Chian School of Medicine
- Nanyang Technological University
- Singapore 636921
- Singapore
- Pinnacle Spine & Scoliosis Centre
| | - Dong-An Wang
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
- Singapore
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Wang Y, Wang X, Shang J, Liu H, Yuan Y, Guo Y, Huang B, Zhou Y. Repairing the ruptured annular fibrosus by using type I collagen combined with citric acid, EDC and NHS: an in vivo study. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2016; 26:884-893. [PMID: 28004245 DOI: 10.1007/s00586-016-4898-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 11/06/2016] [Accepted: 11/23/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To explore the effect of citric acid (CA)-1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/N-hydroxysuccinimide (NHS) collagen gel on repairing annular defects. METHODS Type I collagen was extracted from the rat-tail tendon and crosslinked with CA at different mass ratio using EDC and NHS as crosslinking reagents to prepare four kinds of collagen gels. Forty-eight adult SD rats were divided into first sham group (n = 8), second group (n = 10) which was punctured and injected with CA-EDC/NHS collagen gel, third group (n = 10) which was punctured and injected with CA-EDC/NHS collagen gel, fourth group (n = 10) which was punctured and injected with EDC/NHS collagen gel, and fifth group (n = 10) which was punctured and untreated. X-ray images and magnetic resonance imaging images were obtained before puncture and at the 1st, 2nd, and 4th week after puncture. At each time point, disc height index (%DHI), voxel count and modified MRI Pfirrmann grading were collected and analyzed. All animals were killed at the 4th week to study the morphology. RESULTS The discs in the second group showed only slight degeneration compared with the healthy discs, and the results of %DHI (average 79%), voxel count (average 126.9), Pfirrmann grading (average grade 1.3) and morphology in the second group indicated less degeneration tendency compared with the other three puncture groups at the 4th week (P < 0.05). The annular fibrosus was partially repaired by the collagen gels that bridged the defects. CONCLUSIONS CA-EDC/NHS collagen gel is capable of repairing annular defects induced by needle puncture, which may be closely related to the dose of CA.
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Affiliation(s)
- Yan Wang
- Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Street, Shapingba District, 400037, Chongqing, China
| | - Xiaoting Wang
- Department of Pharmacy, Urumqi General Hospital of Lanzhou Military Region, 359 North Youhao Road, Saybagh District, 830000, Urumqi, China
| | - Jin Shang
- Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Street, Shapingba District, 400037, Chongqing, China
| | - Huan Liu
- Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Street, Shapingba District, 400037, Chongqing, China
| | - Yi Yuan
- Department of Pharmacy, Third Military Medical University, 30 Gaotanyan street, Shapingba District, 400038, Chongqing, China
| | - Yu Guo
- Department of Radiology, Daping Hospital, Third Military Medical University, 10 Changjiang street, Yuzhong District, 400042, Chongqing, China
| | - Bo Huang
- Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Street, Shapingba District, 400037, Chongqing, China.
| | - Yue Zhou
- Department of Orthopedics, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Street, Shapingba District, 400037, Chongqing, China.
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Moriguchi Y, Alimi M, Khair T, Manolarakis G, Berlin C, Bonassar LJ, Härtl R. Biological Treatment Approaches for Degenerative Disk Disease: A Literature Review of In Vivo Animal and Clinical Data. Global Spine J 2016; 6:497-518. [PMID: 27433434 PMCID: PMC4947401 DOI: 10.1055/s-0036-1571955] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 09/24/2015] [Indexed: 12/11/2022] Open
Abstract
STUDY DESIGN Literature review. OBJECTIVE Degenerative disk disease (DDD) has a negative impact on quality of life and is a major cause of morbidity worldwide. There has been a growing interest in the biological repair of DDD by both researchers and clinicians alike. To generate an overview of the recent progress in reparative strategies for the treatment of DDD highlighting their promises and limitations, a comprehensive review of the current literature was performed elucidating data from in vivo animal and clinical studies. METHODS Articles and abstracts available in electronic databases of PubMed, Web of Science, and Google Scholar as of December 2014 were reviewed. Additionally, data from unpublished, ongoing clinical trials was retrieved from clinicaltrials.gov and available abstracts from research forums. Data was extracted from the most recent in vivo animal or clinical studies involving any of the following: (1) treatment with biomolecules, cells, or tissue-engineered constructs and (2) annulus fibrosus repair. RESULTS Seventy-five articles met the inclusion criteria for review. Among these, 17 studies involved humans; 37, small quadrupeds; and 21, large quadrupeds. Findings from all treatments employed demonstrated improvement either in regenerative capacity or in pain attenuation, with the exception of one clinical study. CONCLUSION Published clinical studies on cell therapy have reported encouraging results in the treatment of DDD and resultant back pain. We expect new data to emerge in the near future as treatments for DDD continue to evolve in parallel to our greater understanding of disk health and pathology.
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Affiliation(s)
- Yu Moriguchi
- Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, United States
| | - Marjan Alimi
- Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, United States
| | - Thamina Khair
- Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, United States
| | - George Manolarakis
- Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, United States
| | - Connor Berlin
- Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, United States
| | - Lawrence J. Bonassar
- Department of Biomedical Engineering, Cornell University, Ithaca, New York, United States
| | - Roger Härtl
- Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, United States
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Li Z, Lang G, Chen X, Sacks H, Mantzur C, Tropp U, Mader KT, Smallwood TC, Sammon C, Richards RG, Alini M, Grad S. Polyurethane scaffold with in situ swelling capacity for nucleus pulposus replacement. Biomaterials 2016; 84:196-209. [DOI: 10.1016/j.biomaterials.2016.01.040] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 01/15/2016] [Accepted: 01/19/2016] [Indexed: 12/18/2022]
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Islam A, Chapin K, Younesi M, Akkus O. Computer aided biomanufacturing of mechanically robust pure collagen meshes with controlled macroporosity. Biofabrication 2015. [PMID: 26200002 DOI: 10.1088/1758-5090/7/3/035005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Reconciliation of high strength and high porosity in pure collagen based structures is a major barrier in collagen's use in load-bearing applications. The current study developed a CAD/CAM based electrocompaction method to manufacture highly porous patterned scaffolds using pure collagen. Utilization of computerized scaffold design and fabrication allows the integration of mesh-scaffolds with controlled pore size, shape and spacing. Mechanical properties of fabricated collagen meshes were investigated as a function of number of patterned layers, and with different pore geometries. The tensile stiffness, tensile strength and modulus ranges from 10-50 N cm(-1), 1-6 MPa and 5-40 MPa respectively for all the scaffold groups. These results are within the range of practical usability of different tissue engineering application such as tendon, hernia, stress urinary incontinence or thoracic wall reconstruction. Moreover, 3-fold increase in the layer number resulted in more than 5-fold increases in failure load, toughness and stiffness which suggests that by changing the number of layers and shape of the structure, mechanical properties can be modulated for the aforementioned tissue engineering application. These patterned scaffolds offer a porosity ranging from 0.8 to 1.5 mm in size, a range that is commensurate with pore sizes of repair meshes in the market. The connected macroporosity of the scaffolds facilitated cell-seeding such that cells populated the entire scaffold at the time of seeding. After 3 d of culture, cell nuclei became elongated. These results indicate that the patterned electrochemical deposition method in this study was able to develop mechanically robust, highly porous collagen scaffolds with controlled porosity which not only tries to solve one of the major tissue engineering problems at a fundamental level but also has a significant potential to be used in different tissue engineering applications.
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Affiliation(s)
- Anowarul Islam
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
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Hilmi ABM, Halim AS. Vital roles of stem cells and biomaterials in skin tissue engineering. World J Stem Cells 2015; 7:428-436. [PMID: 25815126 PMCID: PMC4369498 DOI: 10.4252/wjsc.v7.i2.428] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/29/2014] [Accepted: 10/27/2014] [Indexed: 02/06/2023] Open
Abstract
Tissue engineering essentially refers to technology for growing new human tissue and is distinct from regenerative medicine. Currently, pieces of skin are already being fabricated for clinical use and many other tissue types may be fabricated in the future. Tissue engineering was first defined in 1987 by the United States National Science Foundation which critically discussed the future targets of bioengineering research and its consequences. The principles of tissue engineering are to initiate cell cultures in vitro, grow them on scaffolds in situ and transplant the composite into a recipient in vivo. From the beginning, scaffolds have been necessary in tissue engineering applications. Regardless, the latest technology has redirected established approaches by omitting scaffolds. Currently, scientists from diverse research institutes are engineering skin without scaffolds. Due to their advantageous properties, stem cells have robustly transformed the tissue engineering field as part of an engineered bilayered skin substitute that will later be discussed in detail. Additionally, utilizing biomaterials or skin replacement products in skin tissue engineering as strategy to successfully direct cell proliferation and differentiation as well as to optimize the safety of handling during grafting is beneficial. This approach has also led to the cells’ application in developing the novel skin substitute that will be briefly explained in this review.
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Borde B, Grunert P, Härtl R, Bonassar LJ. Injectable, high-density collagen gels for annulus fibrosus repair: An in vitro rat tail model. J Biomed Mater Res A 2014; 103:2571-81. [PMID: 25504661 DOI: 10.1002/jbm.a.35388] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/22/2014] [Accepted: 12/08/2014] [Indexed: 01/08/2023]
Abstract
A herniated intervertebral disc often causes back pain when disc tissue is displaced through a damaged annulus fibrosus. Currently, the only methods available for annulus fibrosus repair involve mechanical closure of defect, which does little to address biological healing in the damaged tissue. Collagen hydrogels are injectable and have been used to repair annulus defects in vivo. In this study, high-density collagen hydrogels at 5, 10, and 15 mg/mL were used to repair defects made to intact rat caudal intervertebral discs in vitro. A group of gels at 15 mg/mL were also cross-linked with riboflavin at 0.03 mM, 0.07 mM, or 0.10 mM. These cross-linked, high-density collagen gels maintained their presence in the defect under loading and contributed positively to the mechanical response of damaged discs. Discs exhibited increases to 95% of undamaged effective equilibrium and instantaneous moduli as well as up to fourfold decreases in effective hydraulic permeability from the damaged discs. These data suggest that high-density collagen gels may be effective at restoring mechanical function of injured discs as well as potential vehicles for the delivery of biological agents such as cells or growth factors that may aid in the repair of the annulus fibrosus.
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Affiliation(s)
- Brandon Borde
- Department of Biomedical Engineering, Cornell University, Ithaca, New York
| | - Peter Grunert
- Department of Neurological Surgery, Weill Cornell Medical College, New York, New York
| | - Roger Härtl
- Department of Neurological Surgery, Weill Cornell Medical College, New York, New York
| | - Lawrence J Bonassar
- Department of Biomedical Engineering, Cornell University, Ithaca, New York.,Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York
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A combined biomaterial and cellular approach for annulus fibrosus rupture repair. Biomaterials 2014; 42:11-9. [PMID: 25542789 DOI: 10.1016/j.biomaterials.2014.11.049] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/19/2014] [Accepted: 11/25/2014] [Indexed: 01/07/2023]
Abstract
Recurrent intervertebral disc (IVD) herniation and degenerative disc disease have been identified as the most important factors contributing to persistent pain and disability after surgical discectomy. An annulus fibrosus (AF) closure device that provides immediate closure of the AF rupture, restores disc height, reduces further disc degeneration and enhances self-repair capacities is an unmet clinical need. In this study, a poly(trimethylene carbonate) (PTMC) scaffold seeded with human bone marrow derived mesenchymal stromal cells (MSCs) and covered with a poly(ester-urethane) (PU) membrane was assessed for AF rupture repair in a bovine organ culture annulotomy model under dynamic load for 14 days. PTMC scaffolds combined with the sutured PU membrane restored disc height of annulotomized discs and prevented herniation of nucleus pulposus (NP) tissue. Implanted MSCs showed an up-regulated gene expression of type V collagen, a potential AF marker, indicating in situ differentiation capability. Furthermore, MSCs delivered within PTMC scaffolds induced an up-regulation of anabolic gene expression and down-regulation of catabolic gene expression in adjacent native disc tissue. In conclusion, the combined biomaterial and cellular approach has the potential to hinder herniation of NP tissue, stabilize disc height, and positively modulate cell phenotype of native disc tissue.
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Guillaume O, Naqvi SM, Lennon K, Buckley CT. Enhancing cell migration in shape-memory alginate–collagen composite scaffolds: In vitro and ex vivo assessment for intervertebral disc repair. J Biomater Appl 2014; 29:1230-46. [DOI: 10.1177/0885328214557905] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Lower lumbar disc disorders pose a significant problem in an aging society with substantial socioeconomic consequences. Both inner tissue (nucleus pulposus) and outer tissue (annulus fibrosus) of the intervertebral disc are affected by such debilitating disorders and can lead to disc herniation and lower back pain. In this study, we developed an alginate–collagen composite porous scaffold with shape-memory properties to fill defects occurring in annulus fibrosus tissue of degenerated intervertebral discs, which has the potential to be administered using minimal invasive surgery. In the first part of this work, we assessed how collagen incorporation on preformed alginate scaffolds influences the physical properties of the final composite scaffold. We also evaluated the ability of annulus fibrosus cells to attach, migrate, and proliferate on the composite alginate–collagen scaffolds compared to control scaffolds (alginate only). In vitro experiments, performed in intervertebral disc-like microenvironmental conditions (low glucose and low oxygen concentrations), revealed that for alginate only scaffolds, annulus fibrosus cells agglomerated in clusters with limited infiltration and migration capacity. In comparison, for alginate–collagen scaffolds, annulus fibrosus cells readily attached and colonized constructs, while preserving their typical fibroblastic-like cell morphology with spreading behavior and intense cytoskeleton expression. In a second part of this study, we investigated the effects of alginate–collagen scaffold when seeded with bone marrow derived mesenchymal stem cells. In vitro, we observed that alginate–collagen porous scaffolds supported cell proliferation and extracellular matrix deposition (collagen type I), with secretion amplified by the local release of transforming growth factor-β3. In addition, when cultured in ex vivo organ defect model, alginate–collagen scaffolds maintained viability of transplanted mesenchymal stem cells for up to 5 weeks. Taken together, these findings illustrate the advantages of incorporating collagen as a means to enhance cell migration and proliferation in porous scaffolds which could be used to augment tissue repair strategies.
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Affiliation(s)
- Olivier Guillaume
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
- Department of Mechanical Engineering, School of Engineering, Trinity College Dublin, Ireland
| | - Syeda Masooma Naqvi
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
- Department of Mechanical Engineering, School of Engineering, Trinity College Dublin, Ireland
| | - Kerri Lennon
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
- Department of Mechanical Engineering, School of Engineering, Trinity College Dublin, Ireland
| | - Conor Timothy Buckley
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
- Department of Mechanical Engineering, School of Engineering, Trinity College Dublin, Ireland
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