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Tan YY, Abdullah D, Abu Kasim NH, Yazid F, Mahamad Apandi NI, Ramanathan A, Soo E, Radzi R, Teh LA. Histological characterization of pulp regeneration using decellularized human dental pulp and mesenchymal stem cells in a feline model. Tissue Cell 2024; 90:102484. [PMID: 39068688 DOI: 10.1016/j.tice.2024.102484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 07/10/2024] [Accepted: 07/18/2024] [Indexed: 07/30/2024]
Abstract
Regenerative endodontics aims to restore pulp tissues, thus preserving the vitality of the tooth. One promising approach involves the utilization of decellularized human dental pulp (DHDP) as a scaffold repopulated with Wharton's Jelly mesenchymal stem cells (WJMSCs). This study aimed to regenerate pulp tissues using DHDP and WJMSCs following pulpectomy in mature canine teeth of a feline animal model and to investigate the histological features of the regenerated pulp. A 12-month-old male domestic shorthaired felines were used as subjects. Teeth were categorized into untreated (Group 1), pulpectomy with mineral trioxide aggregate (MTA) (Group 2), and pulpectomy with DHDP-repopulated scaffold and MTA (Group 3). The animals were sacrificed six weeks post-intervention. H&E and immunohistochemistry using anti-collagen type 1 and laminin antibodies were used to stain the tissue sections. Histological examinations presented pulp-like tissues in Group 3, with tissue components similar to the structures found in Group 1. Immunohistochemical analysis demonstrated the presence of collagen type I and laminin within the regenerated tissues. The root canals of teeth in Group 2 were devoid of pulpal tissue. DHDP with WJMSCs can potentially be used for pulp regeneration, supporting the modality for developing new clinical protocols in stem cell therapy.
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Affiliation(s)
- Yen Yee Tan
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
| | - Dalia Abdullah
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia.
| | - Noor Hayaty Abu Kasim
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Farinawati Yazid
- Department of Family Oral Health, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
| | - Nurul Inaas Mahamad Apandi
- Department of Craniofacial Diagnostics and Biosciences, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
| | - Anand Ramanathan
- Department of Oral & Maxillofacial Clinical Sciences, Faculty of Dentistry, Universiti Malaya, Kuala Lumpur 50603, Malaysia; Oral Cancer Research & Coordinating Center, Faculty of Dentistry, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Eason Soo
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
| | - Rozanaliza Radzi
- Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor Darul Ehsan 43400, Malaysia
| | - Lay Ann Teh
- Department of Restorative Dentistry, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia
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2
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Drewry MD, Shi D, Dailey MT, Rothermund K, Trbojevic S, Almarza AJ, Cui XT, Syed-Picard FN. Enhancing facial nerve regeneration with scaffold-free conduits engineered using dental pulp stem cells and their endogenous, aligned extracellular matrix. J Neural Eng 2024; 21:056015. [PMID: 39197480 PMCID: PMC11406051 DOI: 10.1088/1741-2552/ad749d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 08/28/2024] [Indexed: 09/01/2024]
Abstract
Objective. Engineered nerve conduits must simultaneously enhance axon regeneration and orient axon extension to effectively restore function of severely injured peripheral nerves. The dental pulp contains a population of stem/progenitor cells that endogenously express neurotrophic factors (NTFs), growth factors known to induce axon repair. We have previously generated scaffold-free dental pulp stem/progenitor cell (DPSC) sheets comprising an aligned extracellular matrix (ECM). Through the intrinsic NTF expression of DPSCs and the topography of the aligned ECM, these sheets both induce and guide axon regeneration. Here, the capacity of bioactive conduits generated using these aligned DPSC sheets to restore function in critical-sized nerve injuries in rodents was evaluated.Approach. Scaffold-free nerve conduits were formed by culturing DPSCs on a substrate with aligned microgrooves, inducing the cells to align and deposit an aligned ECM. The sheets were then detached from the substrate and assembled into scaffold-free cylindrical tissues.Main results. In vitroanalyses confirmed that scaffold-free DPSC conduits maintained an aligned ECM and had uniformly distributed NTF expression. Implanting the aligned DPSC conduits across critical-sized defects in the buccal branch of rat facial nerves resulted in the regeneration of a fascicular nerve-like structure and myelinated axon extension across the injury site. Furthermore, compound muscle action potential and stimulated whisker movement measurements revealed that the DPSC conduit treatment promoted similar functional recovery compared to the clinical standard of care, autografts. Significance. This study demonstrates that scaffold-free aligned DPSC conduits supply trophic and guidance cues, key design elements needed to successfully promote and orient axon regeneration. Consequently, these conduits restore function in nerve injuries to similar levels as autograft treatments. These conduits offer a novel bioactive approach to nerve repair capable of improving clinical outcomes and patient quality of life.
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Affiliation(s)
- Michelle D Drewry
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Delin Shi
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Matthew T Dailey
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Oral and Maxillofacial Surgery, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Kristi Rothermund
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Sara Trbojevic
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Alejandro J Almarza
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Xinyan T Cui
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Fatima N Syed-Picard
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
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3
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Calabrese TC, Rothermund K, Gabe CM, Beniash E, Davidson LA, Syed-Picard FN. Self-Assembly of Tooth Root Organoid from Postnatal Human Dental Stem Cells. Tissue Eng Part A 2024; 30:404-414. [PMID: 38126312 PMCID: PMC11392675 DOI: 10.1089/ten.tea.2023.0219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023] Open
Abstract
Challenges remain in simultaneously regenerating the multiple diverse tissues of the tooth root in a spatially organized manner. Previously, our research group has established that scaffold-free tissue engineering approaches enable dental pulp stem/progenitor cells (DPSCs) and periodontal ligament (PDL) stem/progenitor cells (PDLSCs) to self-assemble into dentin-pulp and PDL-cementum organoids, respectively. In this study, we leveraged the innate self-organizing capacity of DPSCs and PDLSCs to now engineer organoids that resemble the full tooth root. Scaffold-free engineered tissues were generated using a heterogeneous mixture of human DPSCs and PDLSCs. Within 2 days of construct formation, PDLSCs and DPSCs became spatially restricted to the periphery and center of the constructs, respectively, emulating their anatomical positions in the tooth root. Histological and microcomputed tomography analyses showed that organoids exhibited a striated mineral pattern with a central unmineralized core, surrounded by a mineralized tissue structure, enclosed within a second peripheral unmineralized tissue, similar to the natural tooth root. Interestingly, DPSCs gave rise to the central unmineralized tissue and the inner portion of the mineralized tissue, and PDLSCs generated the outer portion of the mineralized tissue and the peripheral soft tissue. Quantitative image analysis of immunofluorescent staining revealed increased dentin sialophosphoprotein expression in the region of mineralized tissue associated with DPSCs and increased cementum protein-1 expression in the portion formed by PDLSCs, demonstrating that tooth root organoids comprise two biochemically distinct mineralized tissues characteristic of dentin-like and cementum-like structures, respectively. In addition, PDL-associated protein-1 expression was localized to the peripheral soft tissue, suggesting the formation of a rudimentary PDL-like structure. This study demonstrates that DPSCs and PDLSCs have an inherent ability to orchestrate the formation of a full tooth root-like structure. These organoids present a biomimetic model system to study cellular dynamics driving dental tissue repair or could be utilized therapeutically as biological dental implants.
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Affiliation(s)
- Tia C Calabrese
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Kristi Rothermund
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Claire M Gabe
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Elia Beniash
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania, USA
| | - Lance A Davidson
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania, USA
| | - Fatima N Syed-Picard
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania, USA
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Abdolahinia ED, Golestani S, Seif S, Afra N, Aflatoonian K, Jalalian A, Valizadeh N, Abdollahinia ED. A review of the therapeutic potential of dental stem cells as scaffold-free models for tissue engineering application. Tissue Cell 2024; 86:102281. [PMID: 38070384 DOI: 10.1016/j.tice.2023.102281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 11/19/2023] [Accepted: 11/22/2023] [Indexed: 01/21/2024]
Abstract
In the realm of regenerative medicine, tissue engineering has introduced innovative approaches to facilitate tissue regeneration. Specifically, in pulp tissue engineering, both scaffold-based and scaffold-free techniques have been applied. Relevant articles were meticulously chosen from PubMed, Scopus, and Google Scholar databases through a comprehensive search spanning from October 2022 to December 2022. Despite the inherent limitations of scaffolding, including inadequate mechanical strength for hard tissues, insufficient vents for vessel penetration, immunogenicity, and suboptimal reproducibility-especially with natural polymeric scaffolds-scaffold-free tissue engineering has garnered significant attention. This methodology employs three-dimensional (3D) cell aggregates such as spheroids and cell sheets with extracellular matrix, facilitating precise regeneration of target tissues. The choice of technique aside, stem cells play a pivotal role in tissue engineering, with dental stem cells emerging as particularly promising resources. Their pluripotent nature, non-invasive extraction process, and unique properties render them highly suitable for scaffold-free tissue engineering. This study delves into the latest advancements in leveraging dental stem cells and scaffold-free techniques for the regeneration of various tissues. This paper offers a comprehensive summary of recent developments in the utilization of dental stem cells and scaffold-free methods for tissue generation. It explores the potential of these approaches to advance tissue engineering and their effectiveness in therapies aimed at tissue regeneration.
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Affiliation(s)
- Elaheh Dalir Abdolahinia
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Oral Science and Translation Research, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL, United States.
| | - Shayan Golestani
- Department of Oral and Maxillofacial Surgery, Dental School, Islamic Azad University, Isfahan ( Khorasgan) Branch, Isfahan, Iran
| | - Sepideh Seif
- Faculty of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Narges Afra
- Faculty of Dentistry, Hormozgan University of Medical Sciences, Bandarabbas, Iran
| | - Khotan Aflatoonian
- Department of Restorative Dentistry, Dental School, Shahed University of Medical Sciences, Tehran, Iran
| | - Ali Jalalian
- Faculty of Dentistry, Hamedan University of Medical Sciences, Hamedan, Iran
| | - Nasrin Valizadeh
- Chemistry Department, Sciences Faculty, Azarbaijan Shahid Madani University, Tabriz, Iran
| | - Elham Dalir Abdollahinia
- Fellowship of Endocrinology, Endocrinology Department, Tabriz University of Medical Sciences, Iran.
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5
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Yuan W, Ferreira LDAQ, Yu B, Ansari S, Moshaverinia A. Dental-derived stem cells in tissue engineering: the role of biomaterials and host response. Regen Biomater 2023; 11:rbad100. [PMID: 38223292 PMCID: PMC10786679 DOI: 10.1093/rb/rbad100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 10/31/2023] [Accepted: 11/07/2023] [Indexed: 01/16/2024] Open
Abstract
Dental-derived stem cells (DSCs) are attractive cell sources due to their easy access, superior growth capacity and low immunogenicity. They can respond to multiple extracellular matrix signals, which provide biophysical and biochemical cues to regulate the fate of residing cells. However, the direct transplantation of DSCs suffers from poor proliferation and differentiation toward functional cells and low survival rates due to local inflammation. Recently, elegant advances in the design of novel biomaterials have been made to give promise to the use of biomimetic biomaterials to regulate various cell behaviors, including proliferation, differentiation and migration. Biomaterials could be tailored with multiple functionalities, e.g., stimuli-responsiveness. There is an emerging need to summarize recent advances in engineered biomaterials-mediated delivery and therapy of DSCs and their potential applications. Herein, we outlined the design of biomaterials for supporting DSCs and the host response to the transplantation.
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Affiliation(s)
- Weihao Yuan
- Weintraub Center for Reconstructive Biotechnology, Section of Prosthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Luiza de Almeida Queiroz Ferreira
- Weintraub Center for Reconstructive Biotechnology, Section of Prosthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Restorative Dentistry, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Bo Yu
- Section of Restorative Dentistry, School of Dentistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Sahar Ansari
- Weintraub Center for Reconstructive Biotechnology, Section of Prosthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Alireza Moshaverinia
- Weintraub Center for Reconstructive Biotechnology, Section of Prosthodontics, School of Dentistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences, University of California, Los Angeles, Los Angeles, CA 90095, USA
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Ramli H, Yusop N, Ramli R, Berahim Z, Peiris R, Ghani N. Application of neurotransmitters and dental stem cells for pulp regeneration: A review. Saudi Dent J 2023; 35:387-394. [PMID: 37520592 PMCID: PMC10373085 DOI: 10.1016/j.sdentj.2023.05.004] [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: 12/30/2022] [Revised: 05/07/2023] [Accepted: 05/07/2023] [Indexed: 08/01/2023] Open
Abstract
Introduction Although there have been many studies on stem cells, few have investigated how neurotransmitters and stem cell proliferation interact to regenerate dental pulp. Dental pulp regeneration is an innovative procedure for reviving dental pulp, if feasible for the entire tooth. Upon tooth injury, activated platelets release serotonin and dopamine in bulk to mobilize dental pulp stem cells to mediate natural dental repair. This has induced research on the role of neurotransmitters in increasing the proliferation rate of stem cells. This review also covers prospective future treatments for dental pulp regeneration. Methods A literature search was performed via PubMed and ScienceDirect from 2001 to 2022, using the keywords "neurotransmitter," "stem cell," "tooth regeneration," "tooth repair," "regenerative dentistry," and "dental pulp." Different inclusion/exclusion criteria were used, and the search was restricted to English articles. Results Nine publications reporting neurotransmitter interactions with stem cells for tooth and pulp regeneration were selected. Conclusion Neurotransmitters were found to interact with dental stem cells. Evidence pointing to neurotransmitters as a factor in the increased proliferation of stem cells was found. This review thus gives hope for tooth pulp regeneration and repair.
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Affiliation(s)
- Hidayah Ramli
- Basic and Medical Sciences Unit, School of Dental Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan, Malaysia
| | - Norhayati Yusop
- Basic and Medical Sciences Unit, School of Dental Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan, Malaysia
| | - Rosmaliza Ramli
- Basic and Medical Sciences Unit, School of Dental Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan, Malaysia
| | - Zurairah Berahim
- Periodontic Unit, School of Dental Sciences, Health Campus, Universiti Sains Malaysia, Kelantan 16150, Kota Bharu, Malaysia
| | - Roshan Peiris
- Department of Basic Sciences, Faculty of Dental Sciences, University of Peradeniya, 20400 Peradeniya, Sri Lanka
| | - Nurhafizah Ghani
- Basic and Medical Sciences Unit, School of Dental Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan, Malaysia
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Piglionico SS, Pons C, Romieu O, Cuisinier F, Levallois B, Panayotov IV. In vitro, ex vivo, and in vivo models for dental pulp regeneration. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2023; 34:15. [PMID: 37004591 PMCID: PMC10067643 DOI: 10.1007/s10856-023-06718-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 03/13/2023] [Indexed: 05/03/2023]
Abstract
Based on the concept of tissue engineering (Cells-Scaffold-Bioactive molecules), regenerative endodontics appeared as a new notion for dental endodontic treatment. Its approaches aim to preserve dental pulp vitality (pulp capping) or to regenerate a vascularized pulp-like tissue inside necrotic root canals by cell homing. To improve the methods of tissue engineering for pulp regeneration, numerous studies using in vitro, ex vivo, and in vivo models have been performed. This review explores the evolution of laboratory models used in such studies and classifies them according to different criteria. It starts from the initial two-dimensional in vitro models that allowed characterization of stem cell behavior, through 3D culture matrices combined with dental tissue and finally arrives at the more challenging ex vivo and in vivo models. The travel which follows the elaboration of such models reveals the difficulty in establishing reproducible laboratory models for dental pulp regeneration. The development of well-established protocols and new laboratory ex vivo and in vivo models in the field of pulp regeneration would lead to consistent results, reduction of animal experimentation, and facilitation of the translation to clinical practice.
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Affiliation(s)
- Sofia Silvia Piglionico
- LBN, Univ. Montpellier, Montpellier, France.
- Centro de Investigaciones Odontológicas, National University of Cuyo, Mendoza, Argentina.
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Rothermund K, Calabrese TC, Syed-Picard FN. Differential Effects of Escherichia coli- Versus Porphyromonas gingivalis-derived Lipopolysaccharides on Dental Pulp Stem Cell Differentiation in Scaffold-free Engineered Tissues. J Endod 2022; 48:1378-1386.e2. [PMID: 36108879 PMCID: PMC9764159 DOI: 10.1016/j.joen.2022.08.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/30/2022] [Accepted: 08/30/2022] [Indexed: 11/30/2022]
Abstract
INTRODUCTION To leverage the therapeutic capabilities of dental pulp stem cells (DPSCs) for regenerative endodontic applications, a better understanding of their innate defense and reparative processes is needed. Lipopolysaccharide (LPS) is a major virulent factor of gram-negative bacteria and contributor to endodontic infections. We have developed 3-dimensional scaffold-free DPSC tissues that self-organize into dentin-pulp organoids comprising a mineralized dentin-like tissue on the periphery and an unmineralized pulp-like core. In this study, scaffold-free DPSC constructs were used as controllable experimental models to study the DPSC response to bacterial challenge. METHODS Scaffold-free constructs were engineered using DPSCs isolated from human third molars. To simulate bacterial exposure, DPSC constructs were exposed to either Porphyromonas gingivalis-derived LPS or Escherichia coli-derived LPS. The effects of LPS on DPSC differentiation, proliferation, and apoptosis were evaluated. RESULTS Engineered tissues lacking LPS treatment self-organized into dentin-pulp organoids. LPS treatment did not negatively affect DPSC proliferation or apoptosis in the engineered tissues. Both E. coli LPS and P. gingivalis LPS inhibited the up-regulation of RUNX2 messenger RNA expression and reduced the expression of the odontoblast-associated proteins (P < .05), suggesting that LPS is inhibiting odontoblastic differentiation. However, only E. coli LPS treatment significantly reduced mineral deposition in the DPSC (P < .05) constructs, indicating that E. coli LPS but not P. gingivalis LPS reduced functional differentiation of DPSCs and prevented DPSCs from self-organizing into a dentin-pulp complex-like structure. CONCLUSIONS This study establishes scaffold-free DPSC constructs as models of oral disease. Furthermore, it emphasizes the diversity of LPS derived from different bacterial species and highlights the necessity of using LPS derived from clinically relevant bacteria in basic science investigations.
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Affiliation(s)
- Kristi Rothermund
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Tia C Calabrese
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Fatima N Syed-Picard
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Oral and Craniofacial Sciences, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania; McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania.
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Soares DG, Rosa V. Regenerating the Dental Pulp-Scaffold Materials and Approaches. Dent Clin North Am 2022; 66:643-657. [PMID: 36216451 DOI: 10.1016/j.cden.2022.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Novel technologies and platforms have allowed significant breakthroughs in dental pulp tissue engineering. The development of injectable scaffolds that can be combined with stem cells, growth factors, or other bioactive compounds has enabled the regeneration of functional dental pulps able to secrete dentin in preclinical and clinical studies. Similarly, cell-homing technologies and scaffold-free strategies aim to modulate dental pulp self-regeneration mediated by resident stem cells and can evade some of the technical challenges related to cell-based tissue engineering strategies. This article will discuss emerging technologies and platforms for the clinical applications of dental pulp tissue engineering.
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Affiliation(s)
- Diana Gabriela Soares
- Department of Operative Dentistry, Endodontics and Dental Materials, São Paulo University - USP, Bauru School of Dentistry, Dr. Octavio Pinheiro Brizola, 9-75, Bauru, Sao Paulo 17012-901, Brazil.
| | - Vinicius Rosa
- Faculty of Dentistry, National University of Singapore, 9 Lower Kent Ridge Road, Level 10, Singapore 119085, Singapore.
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Drewry M, Dailey MT, Rothermund K, Backman C, Dahl KN, Syed-Picard FN. Promoting and Orienting Axon Extension Using Scaffold-Free Dental Pulp Stem Cell Sheets. ACS Biomater Sci Eng 2022; 8:814-825. [PMID: 34982537 PMCID: PMC9821555 DOI: 10.1021/acsbiomaterials.1c01517] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Current treatments of facial nerve injury result in poor functional outcomes due to slow and inefficient axon regeneration and aberrant reinnervation. To address these clinical challenges, bioactive scaffold-free cell sheets were engineered using neurotrophic dental pulp stem/progenitor cells (DPCs) and their aligned extracellular matrix (ECM). DPCs endogenously supply high levels of neurotrophic factors (NTFs), growth factors capable of stimulating axonal regeneration, and an aligned ECM provides guidance cues to direct axon extension. Human DPCs were grown on a substrate comprising parallel microgrooves, inducing the cells to align and deposit a linearly aligned, collagenous ECM. The resulting cell sheets were robust and could be easily removed from the underlying substrate. DPC sheets produced NTFs at levels previously shown capable of promoting axon regeneration, and, moreover, inducing DPC alignment increased the expression of select NTFs relative to unaligned controls. Furthermore, the aligned DPC sheets were able to stimulate functional neuritogenic effects in neuron-like cells in vitro. Neuronally differentiated neuroblastoma SH-SY5Y cells produced neurites that were significantly more oriented and less branched when cultured on aligned cell sheets relative to unaligned sheets. These data demonstrate that the linearly aligned DPC sheets can biomechanically support axon regeneration and improve axonal guidance which, when applied to a facial nerve injury, will result in more accurate reinnervation. The aligned DPC sheets generated here could be used in combination with commercially available nerve conduits to enhance their bioactivity or be formed into stand-alone scaffold-free nerve conduits capable of facilitating improved facial nerve recovery.
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Affiliation(s)
- Michelle
D. Drewry
- Department
of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Matthew T. Dailey
- Department
of Oral and Maxillofacial Surgery, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Kristi Rothermund
- Department
of Oral Biology and Center for Craniofacial Regeneration, School of
Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Charles Backman
- Department
of Chemical Engineering, College of Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Kris N. Dahl
- Department
of Chemical Engineering, College of Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States,Department
of Biomedical Engineering, College of Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States,McGowan
Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219, United States,Forensics, Thornton Tomasetti, New York, New York 10271, United States
| | - Fatima N. Syed-Picard
- Department
of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States,Department
of Oral Biology and Center for Craniofacial Regeneration, School of
Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States,McGowan
Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219, United States,. Phone: 412-648-8824
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11
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Ahmed MN, Shi D, Dailey MT, Rothermund K, Drewry MD, Calabrese TC, Cui XT, Syed-Picard FN. Dental Pulp Cell Sheets Enhance Facial Nerve Regeneration via Local Neurotrophic Factor Delivery. Tissue Eng Part A 2021; 27:1128-1139. [PMID: 33164704 PMCID: PMC8616747 DOI: 10.1089/ten.tea.2020.0265] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
An effective strategy for sustained neurotrophic factor (NTF) delivery to sites of peripheral nerve injury (PNI) would accelerate healing and enhance functional recovery, addressing the major clinical challenges associated with the current standard of care. In this study, scaffold-free cell sheets were generated using human dental pulp stem/progenitor cells, that endogenously express high levels of NTFs, for use as bioactive NTF delivery systems. Additionally, the effect of fibroblast growth factor 2 (FGF2) on NTF expression by dental pulp cell (DPC) sheets was evaluated. In vitro analysis confirmed that DPC sheets express high levels of NTF messenger RNA (mRNA) and proteins, and the addition of FGF2 to DPC sheet culture increased total NTF production by significantly increasing the cellularity of sheets. Furthermore, the DPC sheet secretome stimulated neurite formation and extension in cultured neuronal cells, and these functional effects were further enhanced when DPC sheets were cultured with FGF2. These neuritogenic results were reversed by NTF inhibition substantiating that DPC sheets have a positive effect on neuronal cell activity through the production of NTFs. Further evaluation of DPC sheets in a rat facial nerve crush injury model in vivo established that in comparison with untreated controls, nerves treated with DPC sheets had greater axon regeneration through the injury site and superior functional recovery as quantitatively assessed by compound muscle action potential measurements. This study demonstrates the use of DPC sheets as vehicles for NTF delivery that could augment the current methods for treating PNIs to accelerate regeneration and enhance the functional outcome. Impact statement The major challenges associated with current treatments of peripheral nerve injuries (PNIs) are prolonged repair times and insufficient functional recovery. Dental pulp stem/progenitor cells (DPCs) are known to endogenously express high levels of neurotrophic factors (NTFs), growth factors that enhance axon regeneration. In this study, we demonstrate that scaffold-free DPC sheets can act as effective carrier systems to facilitate the delivery and retention of NTF-producing DPCs to sites of PNIs and improve functional nerve regeneration. DPC sheets have high translational feasibility and could augment the current standard of care to enhance the quality of life for patients dealing with PNIs.
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Affiliation(s)
- Meer N. Ahmed
- Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Delin Shi
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Matthew T. Dailey
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Maxillofacial Surgery, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Kristi Rothermund
- Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michelle D. Drewry
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Tia C. Calabrese
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Xinyan T. Cui
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Maxillofacial Surgery, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Fatima N. Syed-Picard
- Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania USA
- Address correspondence to: Fatima N. Syed-Picard, MSE, PhD, Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, 413 Salk Pavilion, 355 Sutherland Drive, Pittsburgh, PA 15213, USA
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12
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Samiei M, Fathi M, Barar J, Fathi N, Amiryaghoubi N, Omidi Y. Bioactive hydrogel-based scaffolds for the regeneration of dental pulp tissue. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2021.102600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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13
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Dissanayaka WL, Zhang C. Scaffold-based and Scaffold-free Strategies in Dental Pulp Regeneration. J Endod 2020; 46:S81-S89. [DOI: 10.1016/j.joen.2020.06.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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14
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Transforaminal and systemic diffusion of an active agent from a zinc oxide eugenol-based endodontic sealer containing hydrocortisone—in an in vivo model. Clin Oral Investig 2020; 24:4395-4402. [DOI: 10.1007/s00784-020-03305-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 04/23/2020] [Indexed: 12/18/2022]
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15
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Wang F, Xie C, Ren N, Bai S, Zhao Y. Human Freeze-dried Dentin Matrix as a Biologically Active Scaffold for Tooth Tissue Engineering. J Endod 2019; 45:1321-1331. [DOI: 10.1016/j.joen.2019.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 07/31/2019] [Accepted: 08/09/2019] [Indexed: 10/25/2022]
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16
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Ahmadian E, Eftekhari A, Dizaj SM, Sharifi S, Mokhtarpour M, Nasibova AN, Khalilov R, Samiei M. The effect of hyaluronic acid hydrogels on dental pulp stem cells behavior. Int J Biol Macromol 2019; 140:245-254. [PMID: 31419560 DOI: 10.1016/j.ijbiomac.2019.08.119] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 08/09/2019] [Accepted: 08/13/2019] [Indexed: 01/12/2023]
Abstract
Dental caries and trauma, particularly in childhood, are among the most prevalent teeth problems, which result in the creation of cavities and probably tooth loss. Thus, novel regenerative approaches with high efficiency and less toxicity are required. Stem cell therapy along with the implementation of scaffolds has provided excellent opportunities in the regeneration of teeth structure. Hyaluronic acid (HA) hydrogels have enticed great attention in the field of regenerative medicine. The unique chemical and structural properties of HA and its derivatives have enabled their application in tissue engineering. Several factors such as the location and type of the lesion, teeth age, the type of capping materials determine the success rate of pulp therapy. HA hydrogels have been considered as biocompatible and safe scaffold supports in human dental cell therapies.
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Affiliation(s)
- Elham Ahmadian
- Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Students' Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Aziz Eftekhari
- Pharmacology and Toxicology Department, Maragheh University of Medical Sciences, Maragheh, Iran
| | - Solmaz Maleki Dizaj
- Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Simin Sharifi
- Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Aygun N Nasibova
- Department of Biophysics and Molecular Biology, Baku State University, Baku, Azerbaijan; Institute of Radiation Problems, National Academy of Sciences of Azerbaijan, Baku, Azerbaijan
| | - Rovshan Khalilov
- Department of Biophysics and Molecular Biology, Baku State University, Baku, Azerbaijan; Institute of Radiation Problems, National Academy of Sciences of Azerbaijan, Baku, Azerbaijan; Joint Ukraine-Azerbaijan International Research and Education Center of Nanobiotechnology and Functional Nanosystems, Drohobych Ukraine & Baku, Azerbaijan
| | - Mohammad Samiei
- Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
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17
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Basu A, Rothermund K, Ahmed MN, Syed-Picard FN. Self-Assembly of an Organized Cementum-Periodontal Ligament-Like Complex Using Scaffold-Free Tissue Engineering. Front Physiol 2019; 10:422. [PMID: 31031642 PMCID: PMC6470283 DOI: 10.3389/fphys.2019.00422] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/27/2019] [Indexed: 01/09/2023] Open
Abstract
A major challenge in regenerating periodontal tissues is emulating its complex structure containing both mineralized and soft tissues. In this study, scaffold-free tissue constructs engineered using periodontal ligament cells (PDLCs), which contain a population of adult stem/progenitor cells, self-assembled into an organized multi-tissue structure comprising a mineralized cementum-like core enclosed within a periodontal ligament (PDL)-like tissue. Scaffold-free engineered constructs were formed by culturing human PDLCs to form a cell sheet on six-well dishes containing two minutien pins placed 7 mm apart. The cell sheet was contracted by the cells to roll into the pins forming a cylindrical construct anchored on either end by the pins. These tissues were approximately 1 mm in diameter and 7 mm long and contained only the cells and their endogenous matrix. These scaffold-free engineered constructs exhibited two structurally distinct tissues, one in the center of the construct and another on the periphery. The center tissue was mineralized and expressed alkaline phosphatase and bone sialoprotein, similar to cementum. The peripheral tissue was not calcified and expressed periodontal ligament-associated protein-1 and periostin, which is characteristic of the periodontal ligament. This tissue organization was seen after in vitro culture and maintained in vivo following subcutaneous implantation in immunocompromised mice. These data demonstrate that scaffold-free tissue engineering facilitates PDLCs to self-assemble into an organized cementum-PDL-like complex. These engineered tissues could be used as implantable grafts to regenerate damaged periodontal tissues or as model systems to study PDLC biology and mechanisms driving organized tissue assembly within the periodontium.
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Affiliation(s)
- Avik Basu
- Department of Oral Biology and Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kristi Rothermund
- Department of Oral Biology and Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Meer N Ahmed
- Department of Oral Biology and Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Fatima N Syed-Picard
- Department of Oral Biology and Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, Pittsburgh, PA, United States
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18
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Buduru SD, Gulei D, Zimta AA, Tigu AB, Cenariu D, Berindan-Neagoe I. The Potential of Different Origin Stem Cells in Modulating Oral Bone Regeneration Processes. Cells 2019; 8:cells8010029. [PMID: 30625993 PMCID: PMC6356555 DOI: 10.3390/cells8010029] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 12/22/2018] [Accepted: 01/02/2019] [Indexed: 12/20/2022] Open
Abstract
Tissue engineering has gained much momentum since the implementation of stem cell isolation and manipulation for regenerative purposes. Despite significant technical improvements, researchers still have to decide which strategy (which type of stem cell) is the most suitable for their specific purpose. Therefore, this short review discusses the advantages and disadvantages of the three main categories of stem cells: embryonic stem cells, mesenchymal stem cells and induced pluripotent stem cells in the context of bone regeneration for dentistry-associated conditions. Importantly, when deciding upon the right strategy, the selection needs to be made in concordance with the morbidity and the life-threatening level of the condition in discussion. Therefore, even when a specific type of stem cell holds several advantages over others, their availability, invasiveness of the collection method and ethical standards become deciding parameters.
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Affiliation(s)
- Smaranda Dana Buduru
- Prosthetics and Dental Materials, Faculty of Dental Medicine, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj-Napoca, 32 Clinicilor Street, 400006 Cluj-Napoca, Romania.
- Stomestet Stomatology Clinic, Calea Manastur 68A Street, 400658 Cluj-Napoca, Romania; .
| | - Diana Gulei
- MEDFUTURE-Research Center for Advanced Medicine, "Iuliu-Hatieganu" University of Medicine and Pharmacy, Marinescu 23 Street, 400337 Cluj-Napoca, Romania.
| | - Alina-Andreea Zimta
- MEDFUTURE-Research Center for Advanced Medicine, "Iuliu-Hatieganu" University of Medicine and Pharmacy, Marinescu 23 Street, 400337 Cluj-Napoca, Romania.
| | - Adrian Bogdan Tigu
- MEDFUTURE-Research Center for Advanced Medicine, "Iuliu-Hatieganu" University of Medicine and Pharmacy, Marinescu 23 Street, 400337 Cluj-Napoca, Romania.
| | - Diana Cenariu
- MEDFUTURE-Research Center for Advanced Medicine, "Iuliu-Hatieganu" University of Medicine and Pharmacy, Marinescu 23 Street, 400337 Cluj-Napoca, Romania.
| | - Ioana Berindan-Neagoe
- MEDFUTURE-Research Center for Advanced Medicine, "Iuliu-Hatieganu" University of Medicine and Pharmacy, Marinescu 23 Street, 400337 Cluj-Napoca, Romania.
- Research Center for Functional Genomics, Biomedicine and Translational Medicine, "Iuliu Hatieganu" University of Medicine and Pharmacy, Marinescu 23 Street, 400337 Cluj-Napoca, Romania.
- Department of Functional Genomics and Experimental Pathology, The Oncology Institute "Prof. Dr. Ion Chiricuta", Republicii 34-36 Street, 400015 Cluj-Napoca, Romania.
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19
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Secreted products of oral bacteria and biofilms impede mineralization of apical papilla stem cells in TLR-, species-, and culture-dependent fashion. Sci Rep 2018; 8:12529. [PMID: 30131595 PMCID: PMC6104064 DOI: 10.1038/s41598-018-30658-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 07/31/2018] [Indexed: 01/09/2023] Open
Abstract
Regenerative endodontics exploits the mineralization potential of stem cells from the apical papilla (SCAPs) in order to promote root maturation of permanent immature teeth. SCAPs may encounter post-disinfection residual bacteria either in planktonic or in biofilm growth mode. Bacterial components bind to Toll-like receptors (TLRs) and trigger pro-inflammatory responses. We hypothesized that biofilm-triggered TLR activation affects the mineralization potential of human SCAPs. SCAPs were challenged with conditioned media derived from standardized dual-species biofilms and planktonic bacterial cultures and their inflammatory status and mineralization capacity were studied. Bacterial products from both growth modes (planktonic vs. biofilm) compromised cell viability, proliferation and mineralization capacity of SCAPs, but in a species- and growth mode-dependent fashion. While TLR4 expression remained unaffected, TLR2 expression was upregulated coinciding with a pro-inflammatory activation of SCAPs. Moreover, TLR and its downstream TGF-β-associated kinase (TAK1) appeared to be blocking mineralization, as inhibition of these factors restored it. In conclusion, bacterial products promoted the pro-inflammatory status and inhibited mineralization of human SCAPs in a TLR-, species-, and culture-dependent fashion. TLR2 emerged as the pivotal mediator of these responses and further research is warranted towards the judicious manipulation of SCAPs in order to modify the untoward events of TLR-priming and signaling.
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20
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Alqahtani Q, Zaky SH, Patil A, Beniash E, Ray H, Sfeir C. Decellularized Swine Dental Pulp Tissue for Regenerative Root Canal Therapy. J Dent Res 2018; 97:1460-1467. [PMID: 30067420 DOI: 10.1177/0022034518785124] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
In the current theme of dental pulp regeneration, biological and synthetic scaffolds are becoming a potential therapy for pulp revitalization. The goal is to provide a suitable environment for cellular infiltration, proliferation, and differentiation. The extracellular matrix (ECM) represents a natural scaffold material resembling the native tissue chemical and mechanical properties. In the past few years, ECM-based scaffolds have shown promising results in terms of progenitor cells recruitment, promotion of constructive remodeling, and modulation of host response. These properties make ECM-derived scaffolds an ideal candidate for pulp regenerative therapy. Development of strategies for clinically relevant tissue engineering using dental pulp extracellular matrix (DP-ECM) can provide an alternative to conventional root canal treatment. In this work, we successfully decellularized ECM derived from porcine dental pulp. The resulting scaffold was characterized using immunostaining (collagen type I, dentin matrix protein 1, dentin sialoprotein, and Von Willebrand factor) and enzyme-linked immunosorbent assay (transforming growth factor β, vascular endothelial growth factor, and basic fibroblast growth factor) for extracellular proteins where the ECM retained its proteins and significant amount of growth factors. Furthermore, a pilot in vivo study was conducted where the matrix was implanted for 8 wk in a dog root canal model. Our in vitro and preliminary in vivo data show that the decellularized ECM supports cellular infiltration together with the expression of pulp-dentin and vascular markers (DSP and CD31) compared to the controls. Herein, we show the feasibility to produce a decellularized ECM scaffold and validate the concept of using ECM-based scaffolds for pulp regeneration.
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Affiliation(s)
- Q Alqahtani
- 1 Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - S H Zaky
- 1 Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,2 Department of Restorative Dentistry, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,3 Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - A Patil
- 1 Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - E Beniash
- 1 Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,3 Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,4 McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - H Ray
- 1 Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,4 McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,5 Department of Endodontics, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - C Sfeir
- 1 Center for Craniofacial Regeneration, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,3 Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,4 McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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21
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Orti V, Collart-Dutilleul PY, Piglionico S, Pall O, Cuisinier F, Panayotov I. Pulp Regeneration Concepts for Nonvital Teeth: From Tissue Engineering to Clinical Approaches. TISSUE ENGINEERING. PART B, REVIEWS 2018; 24:419-442. [PMID: 29724156 DOI: 10.1089/ten.teb.2018.0073] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Following the basis of tissue engineering (Cells-Scaffold-Bioactive molecules), regenerative endodontic has emerged as a new concept of dental treatment. Clinical procedures have been proposed by endodontic practitioners willing to promote regenerative therapy. Preserving pulp vitality was a first approach. Later procedures aimed to regenerate a vascularized pulp in necrotic root canals. However, there is still no protocol allowing an effective regeneration of necrotic pulp tissue either in immature or mature teeth. This review explores in vitro and preclinical concepts developed during the last decade, especially the potential use of stem cells, bioactive molecules, and scaffolds, and makes a comparison with the goals achieved so far in clinical practice. Regeneration of pulp-like tissue has been shown in various experimental conditions. However, the appropriate techniques are currently in a developmental stage. The ideal combination of scaffolds and growth factors to obtain a complete regeneration of the pulp-dentin complex is still unknown. The use of stem cells, especially from pulp origin, sounds promising for pulp regeneration therapy, but it has not been applied so far for clinical endodontics, in case of necrotic teeth. The gap observed between the hope raised from in vitro experiments and the reality of endodontic treatments suggests that clinical success may be achieved without external stem cell application. Therefore, procedures using the concept of cell homing, through evoked bleeding that permit to recreate a living tissue that mimics the original pulp has been proposed. Perspectives for pulp tissue engineering in the near future include a better control of clinical parameters and pragmatic approach of the experimental results (autologous stem cells from cell homing, controlled release of growth factors). In the coming years, this therapeutic strategy will probably become a clinical reality, even for mature necrotic teeth.
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Affiliation(s)
- Valérie Orti
- LBN, Université de Montpellier , Montpellier, France
| | | | | | - Orsolya Pall
- LBN, Université de Montpellier , Montpellier, France
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22
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Itoh Y, Sasaki JI, Hashimoto M, Katata C, Hayashi M, Imazato S. Pulp Regeneration by 3-dimensional Dental Pulp Stem Cell Constructs. J Dent Res 2018; 97:1137-1143. [PMID: 29702010 DOI: 10.1177/0022034518772260] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Dental pulp regeneration therapy for the pulpless tooth has attracted recent attention, and clinical trial studies are underway with the tissue engineering approach. However, there remain many concerns, including the extended period for regenerating the dental pulp. In addition, the use of scaffolds increases the risk of inflammation and infection. To establish a basic technology for novel dental pulp regenerative therapy that allows transplant of pulp-like tissue, we attempted to fabricate scaffold-free 3-dimensional (3D) cell constructs composed of dental pulp stem cells (DPSCs). Furthermore, we assessed viability of these 3D DPSC constructs for dental pulp regeneration through in vitro and in vivo studies. For the in vitro study, we obtained 3D DPSC constructs by shaping sheet-like aggregates of DPSCs with a thermoresponsive hydrogel. DPSCs within constructs remained viable even after prolonged culture; furthermore, 3D DPSC constructs possessed a self-organization ability necessary to serve as a transplant tissue. For the in vivo study, we filled the human tooth root canal with DPSC constructs and implanted it subcutaneously into immunodeficient mice. We found that pulp-like tissues with rich blood vessels were formed within the human root canal 6 wk after implantation. Histologic analyses revealed that transplanted DPSCs differentiated into odontoblast-like mineralizing cells at sites in contact with dentin; furthermore, human CD31-positive endothelial cells were found at the center of regenerated tissue. Thus, the self-organizing ability of 3D DPSC constructs was active within the pulpless root canal in vivo. In addition, blood vessel-rich pulp-like tissues can be formed with DPSCs without requiring scaffolds or growth factors. The technology established in this study allows us to prepare DPSC constructs with variable sizes and shapes; therefore, transplantation of DPSC constructs shows promise for regeneration of pulpal tissue in the pulpless tooth.
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Affiliation(s)
- Y Itoh
- 1 Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Osaka, Japan.,2 Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - J I Sasaki
- 1 Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - M Hashimoto
- 3 Institute of Dental Research, Osaka Dental University, Osaka, Japan
| | - C Katata
- 1 Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Osaka, Japan.,2 Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - M Hayashi
- 2 Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - S Imazato
- 1 Department of Biomaterials Science, Osaka University Graduate School of Dentistry, Osaka, Japan
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23
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Zhang S, Buttler-Buecher P, Denecke B, Arana-Chavez VE, Apel C. A comprehensive analysis of human dental pulp cell spheroids in a three-dimensional pellet culture system. Arch Oral Biol 2018; 91:1-8. [PMID: 29621667 DOI: 10.1016/j.archoralbio.2018.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 01/20/2018] [Accepted: 02/12/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Three-dimensional (3D) cell culture methods are of high importance to studies of biological processes. This is particularly the case with spheroid cultures, which create 3D cell aggregates without the use of exogenous materials. Compared to conventional monolayer cultures, cellular spheroid cultures have been demonstrated to improve multilineage potential and extracellular matrix production. To address this issue in depth, we present a more comprehensive analysis of 3D human dental pulp cell (hDPC) spheroids. DESIGN hDPC spheroids were fabricated by the pellet culture method and were cultured without adding any reagent to induce differentiation. The gene-expression profiles of the 3D and two-dimensional (2D) cultured hDPCs were compared by complementary DNA microarray analysis. Odontoblastic and osteoblastic differentiation marker gene expression was evaluated by quantitative real-time PCR (RT-qPCR). Hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM) were applied to examine the morphology of hDPC spheroids and extracellular matrix components. RESULTS Compared with 2D monolayer culture, microarray analysis identified 405 genes and 279 genes with twofold or greater differential expression after 3 days and 28 days of 3D culture, respectively. In 3D hDPC spheroids, gene ontology analysis revealed upregulation of extracellular matrix-related genes and downregulation of cell growth-related genes. RT-qPCR analysis showed higher expression levels of osteocalcin, dentin sialophosphoprotein, and alkaline phosphatase. TEM revealed the morphological characteristics of the fibrillar collagen-rich matrix and cell-cell interactions. CONCLUSIONS The present findings provide clues to understanding the mechanisms of pellet-cultured hDPCs and contribute to future research in the comparative studies of different 3D culture methods.
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Affiliation(s)
- Siyuan Zhang
- Department of Biohybrid & Medical Textiles, Institute of Applied Medical Engineering, Helmholtz-Institute of Biomedical Engineering, RWTH Aachen University, Aachen, Germany
| | - Patricia Buttler-Buecher
- Department of Conservative Dentistry, Periodontology and Preventive Dentistry, RWTH Aachen University, Aachen, Germany
| | - Bernd Denecke
- Interdisciplinary Center for Clinical Research (IZKF) Aachen, RWTH Aachen University, Germany
| | - Victor E Arana-Chavez
- Department of Biomaterials and Oral Biology, School of Dentistry, University of São Paulo, Brazil
| | - Christian Apel
- Department of Biohybrid & Medical Textiles, Institute of Applied Medical Engineering, Helmholtz-Institute of Biomedical Engineering, RWTH Aachen University, Aachen, Germany.
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24
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Vining KH, Scherba JC, Bever AM, Alexander MR, Celiz AD, Mooney DJ. Synthetic Light-Curable Polymeric Materials Provide a Supportive Niche for Dental Pulp Stem Cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:10.1002/adma.201704486. [PMID: 29215170 PMCID: PMC5788014 DOI: 10.1002/adma.201704486] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/19/2017] [Indexed: 05/08/2023]
Abstract
Dental disease annually affects billions of patients, and while regenerative dentistry aims to heal dental tissue after injury, existing polymeric restorative materials, or fillings, do not directly participate in the healing process in a bioinstructive manner. There is a need for restorative materials that can support native functions of dental pulp stem cells (DPSCs), which are capable of regenerating dentin. A polymer microarray formed from commercially available monomers to rapidly identify materials that support DPSC adhesion is used. Based on these findings, thiol-ene chemistry is employed to achieve rapid light-curing and minimize residual monomer of the lead materials. Several triacrylate bulk polymers support DPSC adhesion, proliferation, and differentiation in vitro, and exhibit stiffness and tensile strength similar to existing dental materials. Conversely, materials composed of a trimethacrylate monomer or bisphenol A glycidyl methacrylate, which is a monomer standard in dental materials, do not support stem cell adhesion and negatively impact matrix and signaling pathways. Furthermore, thiol-ene polymerized triacrylates are used as permanent filling materials at the dentin-pulp interface in direct contact with irreversibly injured pulp tissue. These novel triacrylate-based biomaterials have potential to enable novel regenerative dental therapies in the clinic by both restoring teeth and providing a supportive niche for DPSCs.
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Affiliation(s)
- Kyle H Vining
- Wyss Institute for Biologically Inspired Engineering and Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Jacob C Scherba
- Wyss Institute for Biologically Inspired Engineering and Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Alaina M Bever
- Wyss Institute for Biologically Inspired Engineering and Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Morgan R Alexander
- Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Adam D Celiz
- Wyss Institute for Biologically Inspired Engineering and Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
- Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
| | - David J Mooney
- Wyss Institute for Biologically Inspired Engineering and Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
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Neunzehn J, Pötschke S, Hannig C, Wiesmann HP, Weber MT. Odontoblast-like differentiation and mineral formation of pulpsphere derived cells on human root canal dentin in vitro. Head Face Med 2017; 13:23. [PMID: 29221472 PMCID: PMC5723081 DOI: 10.1186/s13005-017-0156-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 12/01/2017] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND The revitalization or regeneration of the dental pulp is a preferable goal in current endodontic research. In this study, human dental pulp cell (DPC) spheres were applied to human root canal samples to evaluate their potential adoption for physiological tissue-like regeneration of the dental root canal by odontoblastic differentiation as well as cell-induced mineral formation. METHODS DPC were cultivated into three-dimensional cell spheres and seeded on human root canal specimens. The evaluation of sphere formation, tissue-like behavior and differentiation as well as mineral formation of the cells was carried out with the aid of optical light microscopy, immunohistochemical staining and scanning electron microscopy (SEM). RESULTS Spheres and cells migrated out of the spheres showed an intense cell-cell- and cell-dentin-contact with the formation of extra cellular matrix. In addition, the ingrowth of cell processes into dentinal tubules and the interaction of cell processes with the tubule walls were detected by SEM-imaging. Immunohistochemical staining of the odontoblast specific matrix proteins, dentin matrix protein-1, and dentin sialoprotein revealed an odontoblast-like cell differentiation in contact with the dentin surface. This differentiation was confirmed by SEM-imaging of cells with an odontoblast specific phenotype and cell induced mineral formation. CONCLUSIONS The results of the present study reveal the high potential of pulp cells organized in spheres for dental tissue engineering. The odontoblast-like differentiation and the cell induced mineral formation display the possibility of a complete or partial "dentinal filling" of the root canal and the opportunity to combine this method with other current strategies.
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Affiliation(s)
- Jörg Neunzehn
- Technische Universität Dresden, Institute of Material Science, Chair for Biomaterials, Budapester Strasse 27, D-01069, Dresden, Germany.
| | - Sandra Pötschke
- Clinic for Operative and Pediatric Dentistry, Medical Faculty Carl Gustav Carus, TU Dresden, Fetscherstraße 74, D-01307, Dresden, Germany
| | - Christian Hannig
- Clinic for Operative and Pediatric Dentistry, Medical Faculty Carl Gustav Carus, TU Dresden, Fetscherstraße 74, D-01307, Dresden, Germany
| | - Hans-Peter Wiesmann
- Technische Universität Dresden, Institute of Material Science, Chair for Biomaterials, Budapester Strasse 27, D-01069, Dresden, Germany
| | - Marie-Theres Weber
- Clinic for Operative and Pediatric Dentistry, Medical Faculty Carl Gustav Carus, TU Dresden, Fetscherstraße 74, D-01307, Dresden, Germany
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A Novel Strategy to Engineer Pre-Vascularized Full-Length Dental Pulp-like Tissue Constructs. Sci Rep 2017; 7:3323. [PMID: 28607361 PMCID: PMC5468292 DOI: 10.1038/s41598-017-02532-3] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 04/12/2017] [Indexed: 01/10/2023] Open
Abstract
The requirement for immediate vascularization of engineered dental pulp poses a major hurdle towards successful implementation of pulp regeneration as an effective therapeutic strategy for root canal therapy, especially in adult teeth. Here, we demonstrate a novel strategy to engineer pre-vascularized, cell-laden hydrogel pulp-like tissue constructs in full-length root canals for dental pulp regeneration. We utilized gelatin methacryloyl (GelMA) hydrogels with tunable physical and mechanical properties to determine the microenvironmental conditions (microstructure, degradation, swelling and elastic modulus) that enhanced viability, spreading and proliferation of encapsulated odontoblast-like cells (OD21), and the formation of endothelial monolayers by endothelial colony forming cells (ECFCs). GelMA hydrogels with higher polymer concentration (15% w/v) and stiffness enhanced OD21 cell viability, spreading and proliferation, as well as endothelial cell spreading and monolayer formation. We then fabricated pre-vascularized, full-length, dental pulp-like tissue constructs by dispensing OD21 cell-laden GelMA hydrogel prepolymer in root canals of extracted teeth and fabricating 500 µm channels throughout the root canals. ECFCs seeded into the microchannels successfully formed monolayers and underwent angiogenic sprouting within 7 days in culture. In summary, the proposed approach is a simple and effective strategy for engineering of pre-vascularized dental pulp constructs offering potentially beneficial translational outcomes.
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Lee SH, Inaba A, Mohindroo N, Ganesh D, Martin CE, Chugal N, Kim RH, Kang MK, Park NH, Shin KH. Three-dimensional Sphere-forming Cells Are Unique Multipotent Cell Population in Dental Pulp Cells. J Endod 2017; 43:1302-1308. [PMID: 28606672 DOI: 10.1016/j.joen.2017.03.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 03/04/2017] [Accepted: 03/12/2017] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Mesenchymal stem cells (MSCs) are typically cultured as adherent monolayer using a conventional tissue culture technique. However, this technique incompletely reproduces an in vivo microenvironment of stem cells and results in the loss of stemness properties. Three-dimensional (3D) sphere culture is one of the most widely used 3D culture techniques that have been developed to recapitulate the in vivo microenvironment. However, the stemness and multilineage differentiation capacity of spheres derived from dental pulp stem cells (DPSCs) have not been well investigated. METHODS DPSCs were cultured and examined for the sphere-forming ability in serum-free, nonadherent conditions. The expression of pluripotency transcription factors was assayed by reverse transcription quantitative polymerase chain reaction and Western blot analysis. The expression of MSC-associated markers was determined by flow cytometry. Multilineage differentiation capacity was examined by alkaline phosphatase, alizarin red S, and oil red O assays. Subcutaneous transplantation in nude mice was used to examine the in vivo mineralized tissue-forming ability of sphere and adherent monolayer cells derived from DPSCs. RESULTS We showed that DPSCs form spheres. DPSC spheres exhibited a distinct stem cell phenotype characterized by robust expression of pluripotency transcription factors and decreased expression of MSC-associated markers compared with their corresponding adherent monolayer cells. Functionally, DPSC spheres exhibited enhanced in vitro multilineage differentiation capacity. The expression of multilineage differentiation-related genes was also highly increased in DPSC spheres. Furthermore, DPSC sphere cells possessed higher in vivo mineralized tissue-forming ability than adherent monolayer cells. CONCLUSIONS Our findings indicate that sphere-forming cells are unique multipotent cell populations in DPSCs. Our study further suggests that DPSC spheres may provide a unique opportunity for pulp tissue regeneration.
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Affiliation(s)
- Sung Hee Lee
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California
| | - Andrew Inaba
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California; Section of Endodontics, UCLA School of Dentistry, Los Angeles, California
| | - Neha Mohindroo
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California
| | - Deepika Ganesh
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California; Section of Endodontics, UCLA School of Dentistry, Los Angeles, California
| | - Charlotte Ellen Martin
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California
| | - Nadia Chugal
- Section of Endodontics, UCLA School of Dentistry, Los Angeles, California
| | - Reuben H Kim
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California; UCLA Jonsson Comprehensive Cancer Center, Los Angeles, California
| | - Mo K Kang
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California; Section of Endodontics, UCLA School of Dentistry, Los Angeles, California; UCLA Jonsson Comprehensive Cancer Center, Los Angeles, California
| | - No-Hee Park
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California; UCLA Jonsson Comprehensive Cancer Center, Los Angeles, California; David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Ki-Hyuk Shin
- The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, California; UCLA Jonsson Comprehensive Cancer Center, Los Angeles, California.
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Khayat A, Monteiro N, Smith EE, Pagni S, Zhang W, Khademhosseini A, Yelick PC. GelMA-Encapsulated hDPSCs and HUVECs for Dental Pulp Regeneration. J Dent Res 2016; 96:192-199. [PMID: 28106508 DOI: 10.1177/0022034516682005] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pulpal revascularization is commonly used in the dental clinic to obtain apical closure of immature permanent teeth with thin dentinal walls. Although sometimes successful, stimulating bleeding from the periapical area of the tooth can be challenging and in turn may deleteriously affect tooth root maturation. Our objective here was to define reliable methods to regenerate pulp-like tissues in tooth root segments (RSs). G1 RSs were injected with human dental pulp stem cells (hDPSCs) and human umbilical vein endothelial cells (HUVECs) encapsulated in 5% gelatin methacrylate (GelMA) hydrogel. G2 RSs injected with acellular GelMA alone, and G3 empty RSs were used as controls. White mineral trioxide aggregate was used to seal one end of the tooth root segment, while the other was left open. Samples were cultured in vitro in osteogenic media (OM) for 13 d and then implanted subcutaneously in nude rats for 4 and 8 wk. At least 5 sample replicates were used for each experimental group. Analyses of harvested samples found that robust pulp-like tissues formed in G1, GelMA encapsulated hDPSC/HUVEC-filled RSs, and less cellularized host cell-derived pulp-like tissue was observed in the G2 acellular GelMA and G3 empty RS groups. Of importance, only the G1, hDPSC/HUVEC-encapsulated GelMA constructs formed pulp cells that attached to the inner dentin surface of the RS and infiltrated into the dentin tubules. Immunofluorescent (IF) histochemical analysis showed that GelMA supported hDPSC/HUVEC cell attachment and proliferation and also provided attachment for infiltrating host cells. Human cell-seeded GelMA hydrogels promoted the establishment of well-organized neovasculature formation. In contrast, acellular GelMA and empty RS constructs supported the formation of less organized host-derived vasculature formation. Together, these results identify GelMA hydrogel combined with hDPSC/HUVECs as a promising new clinically relevant pulpal revascularization treatment to regenerate human dental pulp tissues.
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Affiliation(s)
- A Khayat
- 1 Tufts University School of Dental Medicine, Boston, MA, USA
| | - N Monteiro
- 1 Tufts University School of Dental Medicine, Boston, MA, USA
| | - E E Smith
- 1 Tufts University School of Dental Medicine, Boston, MA, USA.,2 Department of Cell, Molecular, and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
| | - S Pagni
- 1 Tufts University School of Dental Medicine, Boston, MA, USA
| | - W Zhang
- 1 Tufts University School of Dental Medicine, Boston, MA, USA
| | | | - P C Yelick
- 1 Tufts University School of Dental Medicine, Boston, MA, USA.,2 Department of Cell, Molecular, and Developmental Biology, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA, USA
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Chieruzzi M, Pagano S, Moretti S, Pinna R, Milia E, Torre L, Eramo S. Nanomaterials for Tissue Engineering In Dentistry. NANOMATERIALS 2016; 6:nano6070134. [PMID: 28335262 PMCID: PMC5224610 DOI: 10.3390/nano6070134] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 07/04/2016] [Accepted: 07/18/2016] [Indexed: 02/08/2023]
Abstract
The tissue engineering (TE) of dental oral tissue is facing significant changes in clinical treatments in dentistry. TE is based on a stem cell, signaling molecule, and scaffold triad that must be known and calibrated with attention to specific sectors in dentistry. This review article shows a summary of micro- and nanomorphological characteristics of dental tissues, of stem cells available in the oral region, of signaling molecules usable in TE, and of scaffolds available to guide partial or total reconstruction of hard, soft, periodontal, and bone tissues. Some scaffoldless techniques used in TE are also presented. Then actual and future roles of nanotechnologies about TE in dentistry are presented.
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Affiliation(s)
- Manila Chieruzzi
- Department of Civil and Environmental Engineering-UdR INSTM-University of Perugia, Strada di Pentima, 4-05100 Terni, Italy.
| | - Stefano Pagano
- Department of Surgical and Biomedical Sciences-University of Perugia, S. Andrea delle Fratte, 06156 Perugia, Italy.
| | - Silvia Moretti
- Department of Experimental Medicine-University of Perugia Polo Unico Sant'Andrea delle Fratte, 06132 Perugia, Italy.
| | - Roberto Pinna
- Department of Biomedical Science-University of Sassari viale San Pietro 43/C -07100 Sassari, Italy.
| | - Egle Milia
- Department of Biomedical Science-University of Sassari viale San Pietro 43/C -07100 Sassari, Italy.
| | - Luigi Torre
- Department of Civil and Environmental Engineering-UdR INSTM-University of Perugia, Strada di Pentima, 4-05100 Terni, Italy.
| | - Stefano Eramo
- Department of Surgical and Biomedical Sciences-University of Perugia, S. Andrea delle Fratte, 06156 Perugia, Italy.
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Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy. Stem Cells Int 2016; 2016:9204574. [PMID: 27069484 PMCID: PMC4812497 DOI: 10.1155/2016/9204574] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 01/25/2016] [Accepted: 02/17/2016] [Indexed: 01/09/2023] Open
Abstract
Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration.
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An Optimized Injectable Hydrogel Scaffold Supports Human Dental Pulp Stem Cell Viability and Spreading. Adv Med 2016; 2016:7363579. [PMID: 27294191 PMCID: PMC4884792 DOI: 10.1155/2016/7363579] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 04/03/2016] [Accepted: 04/11/2016] [Indexed: 11/17/2022] Open
Abstract
Introduction. HyStem-C™ is a commercially available injectable hydrogel composed of polyethylene glycol diacrylate (PEGDA), hyaluronan (HA), and gelatin (Gn). These components can be mechanically tuned to enhance cell viability and spreading. Methods. The concentration of PEGDA with an added disulfide bond (PEGSSDA) was varied from 0.5 to 8.0% (w/v) to determine the optimal concentration for injectable clinical application. We evaluated the cell viability of human dental pulp stem cells (hDPSCs) embedded in 2% (w/v) PEGSSDA-HA-Gn hydrogels. Volume ratios of HA : Gn from 100 : 0 to 25 : 75 were varied to encourage hDPSC spreading. Fibronectin (Fn) was added to our model to determine the effect of extracellular matrix protein concentration on hDPSC behavior. Results. Our preliminary data suggests that the hydrogel gelation time decreased as the PEGSSDA cross-linker concentration increased. The PEGSSDA-HA-Gn was biocompatible with hDPSCs, and increased ratios of HA : Gn enhanced cell viability for 14 days. Additionally, cell proliferation with added fibronectin increased significantly over time at concentrations of 1.0 and 10.0 μg/mL in PEGDA-HA-Gn hydrogels, while cell spreading significantly increased at Fn concentrations of 0.1 μg/mL. Conclusions. This study demonstrates that PEG-based injectable hydrogels maintain hDPSC viability and facilitate cell spreading, mainly in the presence of extracellular matrix (ECM) proteins.
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Grimm WD, Giesenhagen B, Hakki S, Schau I, Sirak S, Sletov A, Varga G, Vukovic MA, Widera D. Translational Research and Therapeutic Applications of Neural Crest-Derived Stem Cells in Regenerative Periodontology. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/s40496-015-0067-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Zhang LX, Shen LL, Ge SH, Wang LM, Yu XJ, Xu QC, Yang PS, Yang CZ. Systemic BMSC homing in the regeneration of pulp-like tissue and the enhancing effect of stromal cell-derived factor-1 on BMSC homing. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:10261-10271. [PMID: 26617734 PMCID: PMC4637549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 04/22/2015] [Indexed: 06/05/2023]
Abstract
Pulp regeneration caused by endogenous cells homing has become the new research spot in endodontics. However, the source of functional cells that are involved in and contributed to the reconstituting process has not been identified. In this study, the possible role of systemical BMSC in pulp regeneration and the effect of stromal cell-derived factor-1 (SDF-1) on stem cell recruitment and angiogenesis were evaluated. 54 mice were divided into three groups: SDF-1 group (subcutaneous pockets containing roots with SDF-1 absorbed neutralized collagen gel and the green fluorescent protein (GFP) positive BMSCs transplantation via the tail vein), SDF-1-free group (pockets containing roots with gel alone and GFP + BMSCs transplantation) and Control group (pockets containing roots with gel alone). The animals were sacrificed after the roots were implanted into subcutaneous pockets for 3 weeks. Histomorphometric analysis was performed to evaluate the regenerated tissue in the canal by hematoxylin and eosin (HE) staining. The homing of the transplanted BMSCs was monitored with a fluorescence microscope and immunohistochemical analysis. The expression of ALP in new formed tissue was detected immunohistochemically. Dental-pulp-like tissue and new vessels were regenerated and GFP-positive BMSCs and expression of ALP could be observed in both SDF-1 group and SDF-1-free group. Furthermore, more GFP+ cells, stronger expression of ALP and stronger angiogenesis were found in the SDF-1 group than in the SDF-1-free group. To conclude, systemic BMSC can home to the root canal and participate in dental-pulp-like tissue regeneration. Intracanal application of SDF-1 may enhance BMSC homing efficiency and angiogenesis.
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Affiliation(s)
- Li-Xia Zhang
- Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong UniversityJinan, Shandong, China
- Jinan Stomatological HospitalJinan, Shandong, China
- Department of Periodontology, School of Dentistry, Shandong UniversityJinan, Shandong, China
| | - Li-Li Shen
- Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong UniversityJinan, Shandong, China
- Liaocheng Peoples HospitalLiaocheng, Shandong, China
| | - Shao-Hua Ge
- Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong UniversityJinan, Shandong, China
- Department of Periodontology, School of Dentistry, Shandong UniversityJinan, Shandong, China
| | - Li-Mei Wang
- Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong UniversityJinan, Shandong, China
- Department of Periodontology, School of Dentistry, Shandong UniversityJinan, Shandong, China
| | - Xi-Jiao Yu
- Jinan Stomatological HospitalJinan, Shandong, China
| | - Quan-Chen Xu
- The Affiliated Hospital of Qingdao University Medical CollegeQingdao, Shandong, China
| | - Pi-Shan Yang
- Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong UniversityJinan, Shandong, China
- Department of Periodontology, School of Dentistry, Shandong UniversityJinan, Shandong, China
| | - Cheng-Zhe Yang
- Department of Oral & Maxillofacial Surgery, Qilu Hospital and Institute of Stomatology, Shandong UniversityJinan, Shandong, China
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Hakki SS, Kayis SA, Hakki EE, Bozkurt SB, Duruksu G, Unal ZS, Turaç G, Karaoz E. Comparison of mesenchymal stem cells isolated from pulp and periodontal ligament. J Periodontol 2014; 86:283-91. [PMID: 25325708 DOI: 10.1902/jop.2014.140257] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Cell-based therapy using mesenchymal stem cells (MSCs) seems promising to obtain regeneration of dental tissues. A comparison of tissue sources, including periodontal ligament (PDL) versus pulp (P), could provide critical information to select an appropriate MSC population for designing predictable regenerative therapies. The purpose of this study is to compare the proliferation and stemness and the MSC-specific and mineralized tissue-specific gene expression of P-MSCs and PDL-MSCs. METHODS MSCs were obtained from PDL and P tissue of premolars (n = 3) extracted for orthodontic reasons. MSC proliferation was evaluated using a real-time cell analyzer for 160 hours. Telomerase activity was evaluated by a telomeric repeat amplification protocol assay based on enzyme-linked immunosorbent assay. Total RNA was isolated from the MSCs on day 3. A polymerase chain reaction (PCR) array was used to compare the expression of MSC-specific genes. The expression of mineralized tissue-associated genes, including Type I collagen (COL I), runt-related transcription factor 2 (RunX2), bone sialoprotein (BSP), and osteocalcin (OCN) messenger RNA (mRNA), was evaluated using quantitative real-time PCR. RESULTS Higher proliferation potential and telomerase activity were observed in the P-MSCs compared to PDL-MSCs of premolar teeth. Fourteen of 84 genes related to MSCs were expressed differently in the PDL-MSCs versus the P-MSCs. The expressions of bone morphogenetic protein 2 (BMP2) and BMP6; sex-determining region Y-box 9 (SOX9); integrin, alpha 6 (ITGA6); melanoma cell adhesion molecule (MCAM); phosphatidylinositol glycan anchor biosynthesis, class S (PIGS); prominin 1 (PROM1); ribosomal protein L13A (RPL13A); and microphthalmia-associated transcription factor (MITF) were higher in the P-MSCs compared to the PDL-MSCs, and higher expression of matrix metalloproteinase 2 (MMP2), interleukin (IL)-6, insulin (INS), alanyl (membrane) aminopeptidase (ANPEP), and IL-10 were observed in the PDL-MSCs. However, there was no statistically significant difference in the expression of mineralized tissue-associated genes, including BSP and RunX2, between the P-MSCs and the PDL-MSCs. Higher expression of COL I and lower expression of OCN mRNA transcripts were noted in the PDL-MSCs compared to the P-MSCs. CONCLUSIONS The results of this study suggest that MSCs isolated from P and PDL tissues show different cellular behavior. To increase the predictability of MSC-based regenerative treatment, differences in dental tissue-derived MSCs and favorable aspects of cell sources should be further clarified.
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Affiliation(s)
- Sema S Hakki
- Department of Periodontology, Faculty of Dentistry, Selçuk University, Konya, Turkey
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Today prospects for tissue engineering therapeutic approach in dentistry. ScientificWorldJournal 2014; 2014:151252. [PMID: 25379516 PMCID: PMC4212630 DOI: 10.1155/2014/151252] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/09/2014] [Indexed: 02/08/2023] Open
Abstract
In dental practice there is an increasing need for predictable therapeutic protocols able to regenerate tissues that, due to inflammatory or traumatic events, may suffer from loss of their function. One of the topics arising major interest in the research applied to regenerative medicine is represented by tissue engineering and, in particular, by stem cells. The study of stem cells in dentistry over the years has shown an exponential increase in literature. Adult mesenchymal stem cells have recently been isolated and characterized from tooth-related tissues and they might represent, in the near future, a new gold standard in the regeneration of all oral tissues. The aim of our review is to provide an overview on the topic reporting the current knowledge for each class of dental stem cells and to identify their potential clinical applications as therapeutic tool in various branches of dentistry.
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Dissanayaka WL, Zhu L, Hargreaves KM, Jin L, Zhang C. Scaffold-free Prevascularized Microtissue Spheroids for Pulp Regeneration. J Dent Res 2014; 93:1296-303. [PMID: 25201919 DOI: 10.1177/0022034514550040] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Creating an optimal microenvironment that mimics the extracellular matrix (ECM) of natural pulp and securing an adequate blood supply for the survival of cell transplants are major hurdles that need to be overcome in dental pulp regeneration. However, many currently available scaffolds fail to mimic essential functions of natural ECM. The present study investigated a novel approach involving the use of scaffold-free microtissue spheroids of dental pulp stem cells (DPSCs) prevascularized by human umbilical vein endothelial cells (HUVECs) in pulp regeneration. In vitro-fabricated microtissue spheroids were inserted into the canal space of tooth-root slices and were implanted subcutaneously into immunodeficient mice. Histological examination revealed that, after four-week implantation, tooth-root slices containing microtissue spheroids resulted in well-vascularized and cellular pulp-like tissues, compared with empty tooth-root slices, which were filled with only subcutaneous fat tissue. Immunohistochemical staining indicated that the tissue found in the tooth-root slices was of human origin, as characterized by the expression of human mitochondria, and contained odontoblast-like cells organized along the dentin, as assessed by immunostaining for nestin and dentin sialoprotein (DSP). Vascular structures formed by HUVECs in vitro were successfully anastomosed with the host vasculature upon transplantation in vivo, as shown by immunostaining for human CD31. Collectively, these findings demonstrate that prevascularized, scaffold-free, microtissue spheroids can successfully regenerate vascular dental pulp-like tissue and also highlight the significance of the microtissue microenvironment as an optimal environment for successful pulp-regeneration strategies.
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Affiliation(s)
- W L Dissanayaka
- Endodontics, Comprehensive Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - L Zhu
- Endodontics, Comprehensive Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - K M Hargreaves
- Department of Endodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - L Jin
- Periodontology and Public Health, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - C Zhang
- Endodontics, Comprehensive Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
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