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Tang SN, Bonilla AF, Chahine NO, Colbath AC, Easley JT, Grad S, Haglund L, Le Maitre CL, Leung V, McCoy AM, Purmessur D, Tang SY, Zeiter S, Smith LJ. Controversies in spine research: Organ culture versus in vivo models for studies of the intervertebral disc. JOR Spine 2022; 5:e1235. [PMID: 36601369 PMCID: PMC9799089 DOI: 10.1002/jsp2.1235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 11/30/2022] Open
Abstract
Intervertebral disc degeneration is a common cause of low back pain, the leading cause of disability worldwide. Appropriate preclinical models for intervertebral disc research are essential to achieving a better understanding of underlying pathophysiology and for the development, evaluation, and translation of more effective treatments. To this end, in vivo animal and ex vivo organ culture models are both widely used by spine researchers; however, the relative strengths and weaknesses of these two approaches are a source of ongoing controversy. In this article, members from the Spine and Preclinical Models Sections of the Orthopedic Research Society, including experts in both basic and translational spine research, present contrasting arguments in support of in vivo animal models versus ex vivo organ culture models for studies of the disc, supported by a comprehensive review of the relevant literature. The objective is to provide a deeper understanding of the respective advantages and limitations of these approaches, and advance the field toward a consensus with respect to appropriate model selection and implementation. We conclude that complementary use of several model types and leveraging the unique advantages of each is likely to result in the highest impact research in most instances.
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Affiliation(s)
- Shirley N. Tang
- Department of Biomedical EngineeringThe Ohio State UniversityColumbusOhioUSA
| | - Andres F. Bonilla
- Preclinical Surgical Research Laboratory, Department of Clinical SciencesColorado State UniversityFort CollinsColoradoUSA
| | - Nadeen O. Chahine
- Departments of Orthopedic Surgery and Biomedical EngineeringColumbia UniversityNew YorkNew YorkUSA
| | - Aimee C. Colbath
- Department of Clinical Sciences, College of Veterinary MedicineCornell UniversityIthacaNew YorkUSA
| | - Jeremiah T. Easley
- Preclinical Surgical Research Laboratory, Department of Clinical SciencesColorado State UniversityFort CollinsColoradoUSA
| | | | | | | | - Victor Leung
- Department of Orthopaedics and TraumatologyThe University of Hong KongHong KongSARChina
| | - Annette M. McCoy
- Department of Veterinary Clinical MedicineUniversity of IllinoisUrbanaIllinoisUSA
| | - Devina Purmessur
- Department of Biomedical EngineeringThe Ohio State UniversityColumbusOhioUSA
| | - Simon Y. Tang
- Department of Orthopaedic SurgeryWashington University in St LouisSt LouisMissouriUSA
| | | | - Lachlan J. Smith
- Departments of Orthopaedic Surgery and NeurosurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvaniaUSA
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Peck SH, Bendigo JR, Tobias JW, Dodge GR, Malhotra NR, Mauck RL, Smith LJ. Hypoxic Preconditioning Enhances Bone Marrow-Derived Mesenchymal Stem Cell Survival in a Low Oxygen and Nutrient-Limited 3D Microenvironment. Cartilage 2021; 12:512-525. [PMID: 30971109 PMCID: PMC8461160 DOI: 10.1177/1947603519841675] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE Skeletal tissues such as intervertebral disc and articular cartilage possess limited innate potential to regenerate, in part due to their avascularity and low cell density. Despite recent advances in mesenchymal stem cell (MSC)-based disc and cartilage regeneration, key challenges remain, including the sensitivity of these cells to in vivo microenvironmental stress such as low oxygen and limited nutrition. The objective of this study was to investigate whether preconditioning with hypoxia and/or transforming growth factor-β 3 (TGF-β3) can enhance MSC survival and extracellular matrix production in a low oxygen and nutrient-limited microenvironment. DESIGN MSCs from multiple bovine donors were preconditioned in monolayer in normoxia or hypoxia, with or without TGF-β3, and the global effects on gene expression were examined using microarrays. Subsequently, the effects of preconditioning on MSC survival and extracellular matrix production were examined using low oxygen and nutrient-limited pellet culture experiments. RESULTS Hypoxic preconditioning resulted in upregulation of genes associated with growth, cell-cell signaling, metabolism, and cell stress response pathways, and significantly enhanced MSC survival for all donors in low oxygen and nutrient-limited pellet culture. In contrast, TGF-β3 preconditioning diminished survival. The nature and magnitude of the effects of preconditioning with either hypoxia or TGF-β3 on glycosaminoglycan production were donor dependent. CONCLUSIONS These results strongly support the use of hypoxic preconditioning to improve postimplantation MSC survival in avascular tissues such as disc and cartilage.
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Affiliation(s)
- Sun H. Peck
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
| | - Justin R. Bendigo
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA
| | - John W. Tobias
- Penn Genomic Analysis Core, University of Pennsylvania, Philadelphia, PA, USA
| | - George R. Dodge
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA,Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Neil R. Malhotra
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert L. Mauck
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA,Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
| | - Lachlan J. Smith
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA,Lachlan J. Smith, Department of Neurosurgery, University of Pennsylvania, 371 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA.
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Abstract
The larynx sometimes requires repair and reconstruction due to cancer resection, trauma, stenosis, or developmental disruptions. Bioengineering has provided some scaffolding materials and initial attempts at tissue engineering, especially of the trachea, have been made. The critical issues of providing protection, maintaining a patent airway, and controlling swallowing and phonation, require that the regenerated laryngotracheal cartilages must have mechanical and material properties that closely mimic native tissue. These properties are determined by the cellular and proteomic characteristics of these tissues. However, little is known of these properties for these specific cartilages. This review considers what is known and what issues need to be addressed.
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Affiliation(s)
- Christine M. Pauken
- Head and Neck Regeneration Program, Mayo Clinic Center for Regenerative Medicine, Mayo Clinic, Phoenix, AZ, USA
| | - Richard Heyes
- Head and Neck Regeneration Program, Mayo Clinic Center for Regenerative Medicine, Mayo Clinic, Phoenix, AZ, USA
| | - David G. Lott
- Head and Neck Regeneration Program, Mayo Clinic Center for Regenerative Medicine, Mayo Clinic, Phoenix, AZ, USA,David G. Lott, Head and Neck Regeneration Program, Mayo Clinic Center for Regenerative Medicine, 5777 East Mayo Boulevard, Phoenix, AZ 85054, USA.
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Jaworski LM, Kleinhans KL, Jackson AR. Effects of Oxygen Concentration and Culture Time on Porcine Nucleus Pulposus Cell Metabolism: An in vitro Study. Front Bioeng Biotechnol 2019; 7:64. [PMID: 31001527 PMCID: PMC6454860 DOI: 10.3389/fbioe.2019.00064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/07/2019] [Indexed: 01/07/2023] Open
Abstract
Low back pain is a common ailment that affects millions of individuals each year and is linked to degeneration of the intervertebral discs in the spine. Intervertebral disc degeneration is known to result from an imbalance in anabolic and catabolic activity by disc cells. Due to the avascular nature of the intervertebral disc, oxygen deficiency may occur in the central nucleus pulposus (NP). The resulting hypoxia affects matrix regulation and energy metabolism of disc cells, although the mechanisms are not fully understood. This study investigates in vitro glucose consumption and gene expression by NP cells over time under varying oxygen tensions. Notochordal porcine NP cells were cultured in agarose discs at 21, 5, or 1% oxygen tension for 1, 5, or 10 days. The expression of 10 key matrix genes, as well as Brachyury (T), by NP cells was analyzed using RT-PCR. Glucose consumption was measured using a two-point method. Results show that culture time and oxygen tension significantly affect glucose consumption rates by porcine NP cells. There were also significant changes in T expression based on oxygen level and culture time. The 1% oxygen tension had a significantly higher T expression on day 10 than the other two groups, which may indicate a better maintenance of the notochordal phenotype. MMP 1 and 13 expression increased over time for all groups, while only the 5% group showed an increase over time for MMP 3. TIMP expression followed the direction of MMPs but to a lesser magnitude. Five percent and twenty-one percent oxygen tensions led to decreases in anabolic gene expression while 1% led to increases. Oxygen concentration and culture time significantly impacted glucose consumption rate and the gene expression of matrix regulatory genes with hypoxic conditions most accurately maintaining the proper NP phenotype. This information is valuable not only for understanding disc pathophysiology, but also for harnessing the potential of notochordal NP cells in therapeutic applications.
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Affiliation(s)
- Lukas M Jaworski
- Orthopaedic Biomechanics Laboratory, Department of Biomedical Engineering, University of Miami, Coral Gables, FL, United States
| | - Kelsey L Kleinhans
- Orthopaedic Biomechanics Laboratory, Department of Biomedical Engineering, University of Miami, Coral Gables, FL, United States
| | - Alicia R Jackson
- Orthopaedic Biomechanics Laboratory, Department of Biomedical Engineering, University of Miami, Coral Gables, FL, United States
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Smith LJ, Silverman L, Sakai D, Le Maitre CL, Mauck RL, Malhotra NR, Lotz JC, Buckley CT. Advancing cell therapies for intervertebral disc regeneration from the lab to the clinic: Recommendations of the ORS spine section. JOR Spine 2018; 1:e1036. [PMID: 30895277 PMCID: PMC6419951 DOI: 10.1002/jsp2.1036] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 09/09/2018] [Accepted: 09/10/2018] [Indexed: 12/28/2022] Open
Abstract
Intervertebral disc degeneration is strongly associated with chronic low back pain, a leading cause of disability worldwide. Current back pain treatment approaches (both surgical and conservative) are limited to addressing symptoms, not necessarily the root cause. Not surprisingly therefore, long-term efficacy of most approaches is poor. Cell-based disc regeneration strategies have shown promise in preclinical studies, and represent a relatively low-risk, low-cost, and durable therapeutic approach suitable for a potentially large patient population, thus making them attractive from both clinical and commercial standpoints. Despite such promise, no such therapies have been broadly adopted clinically. In this perspective we highlight primary obstacles and provide recommendations to help accelerate successful clinical translation of cell-based disc regeneration therapies. The key areas addressed include: (a) Optimizing cell sources and delivery techniques; (b) Minimizing potential risks to patients; (c) Selecting physiologically and clinically relevant efficacy metrics; (d) Maximizing commercial potential; and (e) Recognizing the importance of multidisciplinary collaborations and engaging with clinicians from inception through to clinical trials.
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Affiliation(s)
- Lachlan J. Smith
- Department of NeurosurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvania
- Department of Orthopaedic SurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvania
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvania
| | - Lara Silverman
- DiscGenics Inc.Salt Lake CityUtah
- Department of NeurosurgeryUniversity of Tennessee Health Science CenterMemphisTennessee
| | - Daisuke Sakai
- Department of Orthopaedic Surgery, Surgical ScienceTokai University School of MedicineIseharaJapan
| | | | - Robert L. Mauck
- Department of Orthopaedic SurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvania
- Translational Musculoskeletal Research CenterCorporal Michael J. Crescenz VA Medical CenterPhiladelphiaPennsylvania
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvania
| | - Neil R. Malhotra
- Department of NeurosurgeryUniversity of PennsylvaniaPhiladelphiaPennsylvania
| | - Jeffrey C. Lotz
- Department of Orthopaedic SurgeryUniversity of CaliforniaSan FranciscoCalifornia
| | - Conor T. Buckley
- Trinity Centre for BioengineeringTrinity Biomedical Sciences Institute, Trinity College Dublin, The University of DublinDublinIreland
- School of EngineeringTrinity College Dublin, The University of DublinDublinIreland
- Advanced Materials and Bioengineering Research (AMBER) CentreRoyal College of Surgeons in Ireland & Trinity College Dublin, The University of DublinDublinIreland
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Schubert AK, Smink JJ, Pumberger M, Putzier M, Sittinger M, Ringe J. Standardisation of basal medium for reproducible culture of human annulus fibrosus and nucleus pulposus cells. J Orthop Surg Res 2018; 13:209. [PMID: 30134986 PMCID: PMC6106880 DOI: 10.1186/s13018-018-0914-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/15/2018] [Indexed: 11/24/2022] Open
Abstract
Background The lifetime prevalence of degenerative disc disease is dramatically high. Numerous investigations on disc degeneration have been performed on cells from annulus fibrosus (AF) and nucleus pulposus (NP) of the intervertebral disc (IVD) in cell culture experiments utilising a broad variety of basal culture media. Although the basal media differ in nutrient formulation, it is not known whether the choice of the basal media itself has an impact on the cell’s behaviour in vitro. In this study, we evaluated the most common media used for monolayer expansion of AF and NP cells to set standards for disc cell culture. Methods Human AF and NP cells were isolated from cervical discs. Cells were expanded in monolayer until passage P2 using six different common culture media containing alpha-Minimal Essential Medium (alpha-MEM), Dulbecco’s Modified Eagle’s Medium (DMEM) or Ham’s F-12 medium (Ham’s F-12) as single medium or in a mixture of two media (alpha/F-12, DMEM/alpha, DMEM/F-12). Cell morphology, cell growth, glycosaminoglycan production and quantitative gene expression of cartilage- and IVD-related markers aggrecan, collagen type II, forkhead box F1 and keratin 18 were analysed. Statistical analysis was performed with two-way ANOVA testing and Bonferroni compensation. Results AF and NP cells were expandable in all tested media. Both cell types showed similar cell morphology and characteristics of dedifferentiation known for cultured disc cells independently from the media. However, proceeding culture in Ham’s F-12 impeded cell growth of both AF and NP cells. Furthermore, the keratin 18 gene expression profile of NP cells was changed in alpha-MEM and Ham’s F-12. Conclusion The impact of the different media itself on disc cell’s behaviour in vitro was low. However, AF and NP cells were only robust, when DMEM was used as single medium or in a mixture (DMEM/alpha, DMEM/F-12). Therefore, we recommend using these media as standard medium for disc cell culture. Our findings are valuable for the harmonisation of preclinical study results and thereby push the development of cell therapies for clinical treatment of disc degeneration.
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Affiliation(s)
- Ann-Kathrin Schubert
- Tissue Engineering Laboratory and Berlin-Brandenburg Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Augustenburger Platz 1, Südstraße 2, 13353, Berlin, Germany. .,CO.DON AG, Teltow, Germany.
| | | | - Matthias Pumberger
- Center for Musculoskeletal Surgery, Department of Orthopaedics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Michael Putzier
- Center for Musculoskeletal Surgery, Department of Orthopaedics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Michael Sittinger
- Tissue Engineering Laboratory and Berlin-Brandenburg Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Augustenburger Platz 1, Südstraße 2, 13353, Berlin, Germany
| | - Jochen Ringe
- Tissue Engineering Laboratory and Berlin-Brandenburg Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Augustenburger Platz 1, Südstraße 2, 13353, Berlin, Germany
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7
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Krouwels A, Melchels FPW, van Rijen MHP, Öner FC, Dhert WJA, Tryfonidou MA, Creemers LB. Comparing Hydrogels for Human Nucleus Pulposus Regeneration: Role of Osmolarity During Expansion. Tissue Eng Part C Methods 2018; 24:222-232. [PMID: 29457534 DOI: 10.1089/ten.tec.2017.0226] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Hydrogels can facilitate nucleus pulposus (NP) regeneration, either for clinical application or research into mechanisms of regeneration. However, many different hydrogels and culture conditions for human degenerated NP have been employed, making literature data difficult to compare. Therefore, we compared six different hydrogels of natural polymers and investigated the role of serum in the medium and of osmolarity during expansion or redifferentiation in an attempt to provide comparators for future studies. Human NP cells of Thompson grade III discs were cultured in alginate, agarose, fibrin, type II collagen, gelatin methacryloyl (gelMA), and hyaluronic acid-poly(ethylene glycol) hydrogels. Medium containing fetal bovine serum and a serum-free (SF) medium were compared in agarose, gelMA, and type II collagen hydrogels. Isolation and expansion of NP cells in low compared to high osmolarity medium were performed before culture in agarose and type II collagen hydrogels in media of varying osmolarity. NP cells in agarose produced the highest amounts of proteoglycans, followed by cells in type II collagen hydrogels. The absence of serum reduced the total amount of proteoglycans produced by the cells, although incorporation efficiency was higher in type II collagen hydrogels in the absence than in the presence of serum. Isolation and expansion of NP cells in high osmolarity medium improved proteoglycan production during culture in hydrogels, but variation in osmolarity during redifferentiation did not have any effect. Agarose hydrogels seem to be the best option for in vitro culture of human NP cells, but for clinical application, type II collagen hydrogels may be better because, as opposed to agarose, it degrades in time. Although culture in SF medium reduces the amount of proteoglycans produced during redifferentiation culture, isolating and expanding the cells in high osmolarity medium can largely compensate for this loss.
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Affiliation(s)
- Anita Krouwels
- 1 Department of Orthopedics, University Medical Center Utrecht , Utrecht, The Netherlands
| | - Ferry P W Melchels
- 2 Institute of Biological Chemistry, Department of Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot-Watt University , Edinburgh, United Kingdom
| | - Mattie H P van Rijen
- 1 Department of Orthopedics, University Medical Center Utrecht , Utrecht, The Netherlands
| | - F Cumhur Öner
- 1 Department of Orthopedics, University Medical Center Utrecht , Utrecht, The Netherlands
| | - Wouter J A Dhert
- 3 Faculty of Veterinary Medicine, Utrecht University , Utrecht, The Netherlands
| | - Marianna A Tryfonidou
- 4 Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University , Utrecht, The Netherlands
| | - Laura B Creemers
- 1 Department of Orthopedics, University Medical Center Utrecht , Utrecht, The Netherlands
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Hudson KD, Bonassar LJ. Hypoxic Expansion of Human Mesenchymal Stem Cells Enhances Three-Dimensional Maturation of Tissue-Engineered Intervertebral Discs. Tissue Eng Part A 2017; 23:293-300. [PMID: 27903131 DOI: 10.1089/ten.tea.2016.0270] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Culture of three-dimensional (3D) constructs in hypoxic conditions (1-5% O2) has been shown to increase production of extracellular matrix components in primary intervertebral disc (IVD) cells and drive chondrogenesis of human mesenchymal stem cells (hMSCs). Growing evidence suggests that two-dimensional (2D) expansion under hypoxic conditions may have an even greater influence on chondrogenesis in MSCs. This study aims to determine the effects of hypoxia during 2D expansion and subsequent 3D culture on the in vitro maturation of tissue-engineered IVDs (TE-IVDs) made with hMSCs, using a previously developed TE-IVD system. hMSCs were expanded in either hypoxic (5% O2) or normoxic (21% O2) conditions before construction of TE-IVDs. Discs were cultured in 3D in either hypoxic or normoxic conditions to create four experimental groups. Discs made from MSCs expanded in hypoxia were up to 141% stiffer than those made with normoxia-expanded MSCs. Similar patterns were seen in all mechanical properties. Increases in glycosaminoglycan content and collagen content in the nucleus pulposus (NP) were associated with 3D hypoxic culture. A boundary region between the manufactured fibrosus and NP regions developed by 2 weeks and mimicked the organization of the native disc. Hypoxic conditions in both 2D expansion and subsequent 3D culture improved the maturation of TE-IVDs made with hMSCs.
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Affiliation(s)
- Katherine D Hudson
- Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York
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Li P, Shi R, Chen D, Gan Y, Xu Y, Song L, Li S, Zhou Q. Surgical removal and controlled trypsinization of the outer annulus fibrosus improves the bioactivity of the nucleus pulposus in a disc bioreactor culture. BMC Musculoskelet Disord 2016; 17:133. [PMID: 27000557 PMCID: PMC4802625 DOI: 10.1186/s12891-016-0990-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/17/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The maintenance of nucleus pulposus (NP) viability in vitro is difficult. The annulus fibrosus (AF) pathway reflects one nutrient transport channel and may have an important effect on NP viability in disc organ cultures. The present study describes a feasible disc pre-treatment involving the AF and investigates its efficacy in improving NP bioactivity in an in vitro disc bioreactor culture. METHODS Rabbit discs that were randomly assigned to the experimental group (EG) were pretreated via the surgical removal and controlled trypsinization of the outer AF. The discs in the control group (CG) did not receive any special treatment. All discs were organ-cultured in a self-developed bioreactor. Solute transport into the central NP was measured using a methylene blue solution. On days 7 and 14, histological properties, cell viability, cell membrane damage, gene expression and matrix composition within the NP in these two groups were compared with each other and with the corresponding parameters of fresh NP samples. Additionally, the structures of the outer AF and the cartilage endplate (CEP) following pre-treatment were also assessed. RESULTS The outer AF in the EG became disorganized, but no specific changes occurred in the CEP or the inner AF following pre-treatment. The discs in the EG exhibited increased penetration of methylene blue into the central NP. On days 7 and 14, the NP bioactivity in the EG was improved compared with that of the CG in terms of cell viability, cell membrane damage, gene expression profile and matrix synthesis. Moreover, cell viability and matrix synthesis parameters in the EG were more similar to those of fresh samples than they were to the same parameters in the CG on day 14. CONCLUSIONS Using this disc pre-treatment, i.e., the surgical removal and controlled trypsinization of the outer AF, NP bioactivity was better maintained for up to 14 days in an in vitro disc bioreactor culture.
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Affiliation(s)
- Pei Li
- Department of Orthopedic Surgery, Southwest Hospital, Third Military Medical University, Gao Tan Yan 29, Chongqing, 400038, China
| | - Rongmao Shi
- Department of Orthopedic Surgery, Kunming General Hospital of Chengdu Command, Kunming, Yunnan, 650032, China
| | - Daosen Chen
- The 91245 Troops of the Chinese People's Liberation Army, Huludao, Liaoning, 125000, China
| | - Yibo Gan
- Department of Orthopedic Surgery, Southwest Hospital, Third Military Medical University, Gao Tan Yan 29, Chongqing, 400038, China
| | - Yuan Xu
- Department of Orthopedic Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Lei Song
- Department of Orthopedic Surgery, Southwest Hospital, Third Military Medical University, Gao Tan Yan 29, Chongqing, 400038, China
| | - Songtao Li
- Department of Orthopedic Surgery, No. 181 hospital of PLA, Guilin, Guangxi, 541002, China
| | - Qiang Zhou
- Department of Orthopedic Surgery, Southwest Hospital, Third Military Medical University, Gao Tan Yan 29, Chongqing, 400038, China.
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Yan Z, Yin L, Wang Z, Ye J, Zhang Z, Li R, Denduluri SK, Wang J, Wei Q, Zhao L, Lu S, Wang X, Tang S, Shi LL, Lee MJ, He TC, Deng ZL. A Novel Organ Culture Model of Mouse Intervertebral Disc Tissues. Cells Tissues Organs 2015; 201:38-50. [PMID: 26447649 PMCID: PMC4710565 DOI: 10.1159/000439268] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2015] [Indexed: 12/20/2022] Open
Abstract
The intervertebral disc (IVD) is a fibrocartilaginous joint between two vertebral bodies. An IVD unit consists of a gelatinous central nucleus pulposus, encased by the annulus fibrosus, which is sandwiched between cartilaginous endplates (EPs). The IVD homeostasis can be disrupted by injuries, ageing and/or genetic predispositions, leading to degenerative disc disorders and subsequent lower back pain. The complex structure and distinct characteristics of IVDs warrant the establishment of robust in vitro IVD organ culture for studying the etiology and treatment of disc degeneration. Here, we isolate mouse lumbar IVDs and culture the minimal IVD units in submersion or suspension medium supplemented with 2% bovine serum or 10% fetal bovine serum (FBS). We find the minimal IVD units remain healthy for up to 14 days when cultured in submersion culture supplemented with 10% FBS. New bone formation in the EPs of the cultured IVDs can be assessed with calcein labeling. Furthermore, the cultured IVDs can be effectively transduced by recombinant adenovirus, and transgene expression lasts for 2 weeks. Thus, our findings demonstrate that the optimized IVD organ culture system can be used to study IVD biology and screen for biological factors that may prevent, alleviate and/or treat disc degeneration.
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11
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Arkesteijn ITM, Mouser VHM, Mwale F, van Dijk BGM, Ito K. A Well-Controlled Nucleus Pulposus Tissue Culture System with Injection Port for Evaluating Regenerative Therapies. Ann Biomed Eng 2015; 44:1798-807. [PMID: 26294008 PMCID: PMC4837215 DOI: 10.1007/s10439-015-1428-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/11/2015] [Indexed: 11/10/2022]
Abstract
In vitro evaluation of nucleus pulposus (NP) tissue regeneration would be useful, but current systems for NP culture are not ideal for injections. The aim of this study was to develop a long-term culture system for NP tissue that allows injections of regenerative agents. Bovine caudal NPs were harvested and placed in the newly designed culture system. After equilibration of the tissue to 0.3 MPa the volume was fixed and the tissue was cultured for 28 days. The cell viability and extracellular matrix composition remained unchanged during the culture period and gene expression profiles were similar to those obtained in earlier studies. Furthermore, to test the responsiveness of bovine caudal NPs in the system, samples were cultured for 4 days and injected twice (day 1 and 3) with (1) PBS, (2) Link-N, for regeneration, and (3) TNF-α, for degeneration. It was shown that TNF-α increased COX2 gene expression, whereas no effect of Link-N was detected. In conclusion, the newly designed system allows long-term culture of NP tissue, wherein tissue reactions to injected stimulants can be observed.
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Affiliation(s)
- Irene T M Arkesteijn
- Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands
| | - Vivian H M Mouser
- Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.,Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Fackson Mwale
- Division of Orthopaedic Surgery, Lady Davis Institute for Medical Research, McGill University, Montreal, Canada
| | - Bart G M van Dijk
- Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.
| | - Keita Ito
- Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands.,Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
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