This study aimed to compare epithelial cells derived from human embryonic stem cells(hESCs) to human ameloblast-lineage cells (ALCs),as a way to determine their potential use as a cell source for ameloblast regenerati...This study aimed to compare epithelial cells derived from human embryonic stem cells(hESCs) to human ameloblast-lineage cells (ALCs),as a way to determine their potential use as a cell source for ameloblast regeneration.Induced by various concentrations of bone morphogenetic protein 4(BMP4),retinoic acid(RA) and lithium chloride(LiCI) for 7 days,hESCs adopted cobble-stone epithelial phenotype(hESC-derived epithelial cells(ES-ECs)) and expressed cytokeratin 14.Compared with ALCs and oral epithelial cells(OE), ES-ECs expressed amelogenesis-associated genes similar to ALCs.ES-ECs were compared with human fetal skin epithelium,human fetal oral buccal mucosal epithelial cells and human ALCs for their expression pattern of cytokeratins as well.ALCs had relatively high expression levels of cytokeratin 76,which was also found to be upregulated in ES-ECs.Based on the present study,with the similarity of gene expression with ALCs,ES-ECs are a promising potential cell source for regeneration,which are not available in erupted human teeth for regeneration of enamel.展开更多
Dentin matrix protein 1（DMP1） is essential to odontogenesis. Its mutations in human subjects lead to dental problems such as dental deformities, hypomineralization and periodontal impairment. Primarily, DMP1 is cons...Dentin matrix protein 1（DMP1） is essential to odontogenesis. Its mutations in human subjects lead to dental problems such as dental deformities, hypomineralization and periodontal impairment. Primarily, DMP1 is considered as an extracellular matrix protein that promotes hydroxyapatite formation and activates intracellular signaling pathway via interacting with avb3 integrin. Recent in vitro studies suggested that DMP1 might also act as a transcription factor. In this study, we examined whether full-length DMP1 could function as a transcription factor in the nucleus and regulate odontogenesis in vivo. We first demonstrated that a patient with the DMP1M1 V mutation, which presumably causes a loss of the secretory DMP1 but does not affect the nuclear translocation of DMP1, shows a typical rachitic tooth defect. Furthermore, we generated transgenic mice expressingNLSDMP1, in which the endoplasmic reticulum（ER） entry signal sequence of DMP1 was replaced by a nuclear localization signal（NLS） sequence, under the control of a 3.6 kb rat type I collagen promoter plus a 1.6 kb intron 1. We then crossbred theNLSDMP1 transgenic mice with Dmp1 null mice to express the NLSDMP1 in Dmp1-deficient genetic background. Although immunohistochemistry demonstrated thatNLSDMP1 was localized in the nuclei of the preodontoblasts and odontoblasts, the histological, morphological and biochemical analyses showed that it failed to rescue the dental and periodontal defects as well as the delayed tooth eruption in Dmp1 null mice. These data suggest that the full-length DMP1 plays no apparent role in the nucleus during odontogenesis.展开更多
Within the nervous system, regeneration is limited, and this is due to the small amount of neural stem cells, the inhibitory origin of the stem cell niche and often to the development of a scar which constitutes a mec...Within the nervous system, regeneration is limited, and this is due to the small amount of neural stem cells, the inhibitory origin of the stem cell niche and often to the development of a scar which constitutes a mechanical barrier for the regeneration. Regarding these aspects, many efforts have been done in the re- search of a cell component that combined with scaffolds and growth factors could be suitable for nervous regeneration in regenerative medicine approaches. Autologous mesenchymal stem cells represent nowa- days the ideal candidate for this aim, thank to their multipotency and to their amount inside adult tissues. However, issues in their harvesting, through the use of invasive techniques, and problems involved in their ageing, require the research of new autologous sources. To this purpose, the recent discovery of a stem cells component in teeth, and which derive from neural crest cells, has came to the light the possibility of using dental stem cells in nervous system regeneration. In this work, in order to give guidelines on the use of dental stem cells for neural regeneration, we briefly introduce the concepts of regeneration and regenerative medicine, we then focus the attention on odontogenesis, which involves the formation and the presence of a stem component in different parts of teeth, and finally we describe some experimental approaches which are exploiting dental stem cells for neural studies.展开更多
Cementum,a mineralized connective tissue that covers the tooth root,is crucial in protecting the root from resorption,maintaining occlusal relationships,and supporting tooth function.Cementocytes are embedded within t...Cementum,a mineralized connective tissue that covers the tooth root,is crucial in protecting the root from resorption,maintaining occlusal relationships,and supporting tooth function.Cementocytes are embedded within the cementum matrix and extend dendritic processes through the canaliculi.They are thought to be mechanosensitive,responding to changes in mechanical loading,and are physiologically responsive cells associated with the formation of cellular cementum in response to variations in functional demands on the tooth.The wingless and int(Wnt)signaling pathway,which controls cell fate and regulates growth,development,and homeostasis in the body,plays a pivotal regulatory role in normal biological development and disease progression.Currently,the mechanisms by which the Wnt signaling pathway influences cementogenesis and regeneration remain controversial.Research findings on the roles of Wnt/β-catenin signaling in cementoblast differentiation and function have been mixed.Some studies indicate that activating this pathway enhances cementoblast differentiation,while others suggest that Wnt signaling may inhibit it,favoring cell proliferation instead.This paper reviews the structure and physiological roles of cementum,focusing on how Wnt signaling influences the growth and differentiation of cementoblasts.We emphasize the pivotal role of the Wnt pathway in cementum formation and development,as well as in root resorption and repair,and hypothesize that maintaining low Wnt/β-catenin levels is crucial to achieving an optimal balance between cementoblast proliferation and differentiation.Finally,we propose periodontal regeneration treatment strategies based on the Wnt signaling pathway and suggest future research directions.展开更多
The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood.We report a cell lineage and atlas of developing mouse teeth.We performed a large-scale(92,688 cells)single cell RNA se...The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood.We report a cell lineage and atlas of developing mouse teeth.We performed a large-scale(92,688 cells)single cell RNA sequencing,tracing the cell trajectories during odontogenesis from embryonic days 10.5 to 16.5.Combined with an assay for transposase-accessible chromatin with high-throughput sequencing,our results suggest that mesenchymal cells show the specific transcriptome profiles to distinguish the tooth types.Subsequently,we identified key gene regulatory networks in teeth and bone formation and uncovered spatiotemporal patterns of odontogenic mesenchymal cells.CD24^(+)and Plac8^(+)cells from the mesenchyme at the bell stage were distributed in the upper half and preodontoblast layer of the dental papilla,respectively,which could individually induce nonodontogenic epithelia to form tooth-like structures.Specifically,the Plac8^(+)tissue we discovered is the smallest piece with the most homogenous cells that could induce tooth regeneration to date.Our work reveals previously unknown heterogeneity and spatiotemporal patterns of tooth germs that may lead to tooth regeneration for regenerative dentistry.展开更多
Therapeutic options are quite limited in clinics for the successful repair of infected/degenerated tissues.Although the prevalent treatment is the complete removal of the whole infected tissue,this leads to a loss of ...Therapeutic options are quite limited in clinics for the successful repair of infected/degenerated tissues.Although the prevalent treatment is the complete removal of the whole infected tissue,this leads to a loss of tissue function and serious complications.Herein the dental pulp infection,as one of the most common dental problems,was selected as a clinically relevant case to regenerate using a multifunctional nanotherapeutic approach.For this,a mesoporous bioactive glass nano-delivery system incorporating silicate,calcium,and copper as well as loading epidermal growth factor(EGF)was designed to provide antibacterial/pro-angiogenic and osteo/odontogenic multiple therapeutic effects.Amine-functionalized Cu-doped bioactive glass nanospheres(Cu-BGn)were prepared to be 50–60 nm in size,mesoporous,positive-charged and bone-bioactive.The Cu-BGn could release bioactive ions(copper,calcium and silicate ions)with therapeutically-effective doses.The Cu-BGn treatment to human umbilical vein endothelial cells(HUVEC)led to significant enhancement of the migration,tubule formation and expression of angiogenic gene(e.g.vascular endothelial growth factor,VEGF).Furthermore,the EGF-loaded Cu-BGn(EGF@Cu-BGn)showed pro-angiogenic effects with antibacterial activity against E.faecalis,a pathogen commonly involved in the pulp infection.Of note,under the co-culture condition of HUVEC with E.faecalis,the secretion of VEGF was up-regulated.In addition,the osteo/odontogenic stimulation of the EGF@Cu-BGn was evidenced with human dental pulp stem cells.The local administration of the EGF@Cu-BGn in a rat molar tooth defect infected with E.faecalis revealed significant in vivo regenerative capacity,highlighting the nanotherapeutic uses of the multifunctional nanoparticles for regenerating infected/damaged hard tissues.展开更多
基金supported by NIH/NIDCR grants R03 DE019507-02 to Yan Zhang,R21 D E0 18633 to Pamela K DenBesten and 2011SCU 11999-3/ NSFC81200760to Li-Wei Zheng
文摘This study aimed to compare epithelial cells derived from human embryonic stem cells(hESCs) to human ameloblast-lineage cells (ALCs),as a way to determine their potential use as a cell source for ameloblast regeneration.Induced by various concentrations of bone morphogenetic protein 4(BMP4),retinoic acid(RA) and lithium chloride(LiCI) for 7 days,hESCs adopted cobble-stone epithelial phenotype(hESC-derived epithelial cells(ES-ECs)) and expressed cytokeratin 14.Compared with ALCs and oral epithelial cells(OE), ES-ECs expressed amelogenesis-associated genes similar to ALCs.ES-ECs were compared with human fetal skin epithelium,human fetal oral buccal mucosal epithelial cells and human ALCs for their expression pattern of cytokeratins as well.ALCs had relatively high expression levels of cytokeratin 76,which was also found to be upregulated in ES-ECs.Based on the present study,with the similarity of gene expression with ALCs,ES-ECs are a promising potential cell source for regeneration,which are not available in erupted human teeth for regeneration of enamel.
基金supported by NIH grants DE018486 and R56 DE022789 to Jian-Quan Feng, DE023365 to Yong-Bo Lu and a scholarship from the Chinese State Scholarship Fund to Shu-Xian Lin (2010627108)
文摘Dentin matrix protein 1（DMP1） is essential to odontogenesis. Its mutations in human subjects lead to dental problems such as dental deformities, hypomineralization and periodontal impairment. Primarily, DMP1 is considered as an extracellular matrix protein that promotes hydroxyapatite formation and activates intracellular signaling pathway via interacting with avb3 integrin. Recent in vitro studies suggested that DMP1 might also act as a transcription factor. In this study, we examined whether full-length DMP1 could function as a transcription factor in the nucleus and regulate odontogenesis in vivo. We first demonstrated that a patient with the DMP1M1 V mutation, which presumably causes a loss of the secretory DMP1 but does not affect the nuclear translocation of DMP1, shows a typical rachitic tooth defect. Furthermore, we generated transgenic mice expressingNLSDMP1, in which the endoplasmic reticulum（ER） entry signal sequence of DMP1 was replaced by a nuclear localization signal（NLS） sequence, under the control of a 3.6 kb rat type I collagen promoter plus a 1.6 kb intron 1. We then crossbred theNLSDMP1 transgenic mice with Dmp1 null mice to express the NLSDMP1 in Dmp1-deficient genetic background. Although immunohistochemistry demonstrated thatNLSDMP1 was localized in the nuclei of the preodontoblasts and odontoblasts, the histological, morphological and biochemical analyses showed that it failed to rescue the dental and periodontal defects as well as the delayed tooth eruption in Dmp1 null mice. These data suggest that the full-length DMP1 plays no apparent role in the nucleus during odontogenesis.
文摘Within the nervous system, regeneration is limited, and this is due to the small amount of neural stem cells, the inhibitory origin of the stem cell niche and often to the development of a scar which constitutes a mechanical barrier for the regeneration. Regarding these aspects, many efforts have been done in the re- search of a cell component that combined with scaffolds and growth factors could be suitable for nervous regeneration in regenerative medicine approaches. Autologous mesenchymal stem cells represent nowa- days the ideal candidate for this aim, thank to their multipotency and to their amount inside adult tissues. However, issues in their harvesting, through the use of invasive techniques, and problems involved in their ageing, require the research of new autologous sources. To this purpose, the recent discovery of a stem cells component in teeth, and which derive from neural crest cells, has came to the light the possibility of using dental stem cells in nervous system regeneration. In this work, in order to give guidelines on the use of dental stem cells for neural regeneration, we briefly introduce the concepts of regeneration and regenerative medicine, we then focus the attention on odontogenesis, which involves the formation and the presence of a stem component in different parts of teeth, and finally we describe some experimental approaches which are exploiting dental stem cells for neural studies.
基金National Natural Science Foundation of China(Nos.82471020 and 82401159)Sichuan Science and Technology Program(No.2024NSFSC1593),China。
文摘Cementum,a mineralized connective tissue that covers the tooth root,is crucial in protecting the root from resorption,maintaining occlusal relationships,and supporting tooth function.Cementocytes are embedded within the cementum matrix and extend dendritic processes through the canaliculi.They are thought to be mechanosensitive,responding to changes in mechanical loading,and are physiologically responsive cells associated with the formation of cellular cementum in response to variations in functional demands on the tooth.The wingless and int(Wnt)signaling pathway,which controls cell fate and regulates growth,development,and homeostasis in the body,plays a pivotal regulatory role in normal biological development and disease progression.Currently,the mechanisms by which the Wnt signaling pathway influences cementogenesis and regeneration remain controversial.Research findings on the roles of Wnt/β-catenin signaling in cementoblast differentiation and function have been mixed.Some studies indicate that activating this pathway enhances cementoblast differentiation,while others suggest that Wnt signaling may inhibit it,favoring cell proliferation instead.This paper reviews the structure and physiological roles of cementum,focusing on how Wnt signaling influences the growth and differentiation of cementoblasts.We emphasize the pivotal role of the Wnt pathway in cementum formation and development,as well as in root resorption and repair,and hypothesize that maintaining low Wnt/β-catenin levels is crucial to achieving an optimal balance between cementoblast proliferation and differentiation.Finally,we propose periodontal regeneration treatment strategies based on the Wnt signaling pathway and suggest future research directions.
基金supported by the National Key Research and Development Program of China Stem Cell and Translational Research,China(2017YFA0104800)the Research Funds from Health@InnoHK Program launched by Innovation Technology Commission of the Hong Kong SAR,China+4 种基金National Natural Science Foundation of China(81570944 and 92068201)Science and Technology Planning Project of Guangdong Province,China(2020B1212060052)High-level Hospital Construction Project(DFJHBF202110)Youth Innovation Promotion of the Chinese Academy of Sciences(2019348)Guangzhou Key Medical Disciplines(2021–2023)。
文摘The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood.We report a cell lineage and atlas of developing mouse teeth.We performed a large-scale(92,688 cells)single cell RNA sequencing,tracing the cell trajectories during odontogenesis from embryonic days 10.5 to 16.5.Combined with an assay for transposase-accessible chromatin with high-throughput sequencing,our results suggest that mesenchymal cells show the specific transcriptome profiles to distinguish the tooth types.Subsequently,we identified key gene regulatory networks in teeth and bone formation and uncovered spatiotemporal patterns of odontogenic mesenchymal cells.CD24^(+)and Plac8^(+)cells from the mesenchyme at the bell stage were distributed in the upper half and preodontoblast layer of the dental papilla,respectively,which could individually induce nonodontogenic epithelia to form tooth-like structures.Specifically,the Plac8^(+)tissue we discovered is the smallest piece with the most homogenous cells that could induce tooth regeneration to date.Our work reveals previously unknown heterogeneity and spatiotemporal patterns of tooth germs that may lead to tooth regeneration for regenerative dentistry.
基金a National Research Foundation of Korea(NRF)grant funded by the Ministry of Science and ICT(2019R1C1C1002490,2018R1A2B3003446)by the Global Research Development Center Program(2018K1A4A3A01064257)by the Priority Research Center Program provided by the Ministry of Education(2019R1A6A1A11034536)。
文摘Therapeutic options are quite limited in clinics for the successful repair of infected/degenerated tissues.Although the prevalent treatment is the complete removal of the whole infected tissue,this leads to a loss of tissue function and serious complications.Herein the dental pulp infection,as one of the most common dental problems,was selected as a clinically relevant case to regenerate using a multifunctional nanotherapeutic approach.For this,a mesoporous bioactive glass nano-delivery system incorporating silicate,calcium,and copper as well as loading epidermal growth factor(EGF)was designed to provide antibacterial/pro-angiogenic and osteo/odontogenic multiple therapeutic effects.Amine-functionalized Cu-doped bioactive glass nanospheres(Cu-BGn)were prepared to be 50–60 nm in size,mesoporous,positive-charged and bone-bioactive.The Cu-BGn could release bioactive ions(copper,calcium and silicate ions)with therapeutically-effective doses.The Cu-BGn treatment to human umbilical vein endothelial cells(HUVEC)led to significant enhancement of the migration,tubule formation and expression of angiogenic gene(e.g.vascular endothelial growth factor,VEGF).Furthermore,the EGF-loaded Cu-BGn(EGF@Cu-BGn)showed pro-angiogenic effects with antibacterial activity against E.faecalis,a pathogen commonly involved in the pulp infection.Of note,under the co-culture condition of HUVEC with E.faecalis,the secretion of VEGF was up-regulated.In addition,the osteo/odontogenic stimulation of the EGF@Cu-BGn was evidenced with human dental pulp stem cells.The local administration of the EGF@Cu-BGn in a rat molar tooth defect infected with E.faecalis revealed significant in vivo regenerative capacity,highlighting the nanotherapeutic uses of the multifunctional nanoparticles for regenerating infected/damaged hard tissues.
