The esophagus is a tubular organ essential for maintaining normal eating function in humans.However,the replacement of the esophagus remains challenging in clinical settings.Although tissue engineering scaffolds are a...The esophagus is a tubular organ essential for maintaining normal eating function in humans.However,the replacement of the esophagus remains challenging in clinical settings.Although tissue engineering scaffolds are a promising alternative solution,their fabrication is difficult due to the complex structure and function of the esophagus.This review describes the existing fabrication methods for esophageal tubular scaffolds,including decellularization,casting,electrospinning,three dimensional(3 D)bioprinting,and pin-frogging.Also discussed are the stimulation cues of the fabricated esophageal tubular scaffold that induce esophageal muscle and epithelial cells.Finally,this review emphasizes three important concerns for esophageal tubular scaffolds:leakage and porosity,elasticity and proliferation of smooth muscle cells,and biocompatibility and structural fidelity of biomaterials.展开更多
Cardiac tissue engineering aims to efficiently replace or repair injured heart tissue using scaffolds,relevant cells,or their combination.While the combination of scaffolds and relevant cells holds the potential to ra...Cardiac tissue engineering aims to efficiently replace or repair injured heart tissue using scaffolds,relevant cells,or their combination.While the combination of scaffolds and relevant cells holds the potential to rapidly remuscularize the heart,thereby avoiding the slow process of cell recruitment,the proper ex vivo cellularization of a scaffold poses a substantial challenge.First,proper diffusion of nutrients and oxygen should be provided to the cell-seeded scaffold.Second,to generate a functional tissue construct,cells can benefit from physiological-like conditions.To meet these challenges,we developed a modular bioreactor for the dynamic cellularization of full-thickness cardiac scaffolds under synchronized mechanical and electrical stimuli.In this unique bioreactor system,we designed a cyclic mechanical load that mimics the left ventricle volume inflation,thus achieving a steady stimulus,as well as an electrical stimulus with an action potential profile to mirror the cells’microenvironment and electrical stimuli in the heart.These mechanical and electrical stimuli were synchronized according to cardiac physiology and regulated by constant feedback.When applied to a seeded thick porcine cardiac extracellular matrix(pcECM)scaffold,these stimuli improved the proliferation of mesenchymal stem/stromal cells(MSCs)and induced the formation of a dense tissue-like structure near the scaffold’s surface.Most importantly,after 35 d of cultivation,the MSCs presented the early cardiac progenitor markers Connexin-43 andα-actinin,which were absent in the control cells.Overall,this research developed a new bioreactor system for cellularizing cardiac scaffolds under cardiac-like conditions,aiming to restore a sustainable dynamic living tissue that can bear the essential cardiac excitation–contraction coupling.展开更多
Oral and maxillofacial reconstruction represents one of the most complex challenges in plastic and reconstructive surgery,requiring the restoration of both form and function in highly specialized anatomical regions.Tr...Oral and maxillofacial reconstruction represents one of the most complex challenges in plastic and reconstructive surgery,requiring the restoration of both form and function in highly specialized anatomical regions.Traditional strategies,including local flaps and autologous bone grafts,remain fundamental but are limited by donor-site morbidity,tissue availability,and unpredictable outcomes.Recent advances in regenerative medicine have shifted the paradigm from repair to true regeneration,harnessing stem cells,biomaterial scaffolds,and signaling molecules in a synergistic approach.Dental-and craniofacial tissue-derived mesenchymal stem cells,along with adipose-derived stem cells,demonstrate significant potential for alveolar bone repair,periodontal regeneration,and soft tissue augmentation.Innovations in three-dimensional printing and bioactive matrices have enabled precise scaffold design and improved vascularization,thereby enhancing both predictability and esthetic outcomes.This mini review focuses on the synergistic role of stem cells,scaffolds,and signaling molecules in oral and maxillofacial regeneration,with an emphasis on the unique contributions of periodontists.By integrating periodontal biology with reconstructive techniques,a new collaborative framework is emerging to optimize regenerative outcomes.Future research must address clinical translation,large-scale trials,cost-effectiveness,and personalized approaches to fully realize the promise of regenerative surgery.展开更多
Tissue engineering and regenera-tive medicine have shown signifi-cant potential for repairing and regenerating damaged tissues and can be used to provide personalized treatment plans,with broad applica-tion prospects....Tissue engineering and regenera-tive medicine have shown signifi-cant potential for repairing and regenerating damaged tissues and can be used to provide personalized treatment plans,with broad applica-tion prospects.In this special issue,Bin Li’s team outlines the latest advances in minimally invasive implantable biomaterials for bone regeneration and different methods of achieving osteogenesis,with a focus on bioceramics and polymer materials and their applications in bone healing,vertebral augmenta-tion,implant fixation,tumor treatment of bone,and treatment of infections related to bone defects.Xinquan Jiang’s team constructs a novel photo-responsive multifunctional polyetheretherketone(PEEK)-based implant material(sPEEK/BP/E7)through the self-assembly of black phosphorus(BP)nanoplatelets,bioinspired poly-dopamine(PDA),and the biologically active short peptide E7 on sPEEK.The material exhibits effective osteogenic effects and good sterilization performance,providing a new idea for clinical application.展开更多
The ability to replicate the microenvironment of the human body through the fabrication of scaffolds is a significant achievement in the biomedical field.However,the search for the ideal scaffold is still in its infan...The ability to replicate the microenvironment of the human body through the fabrication of scaffolds is a significant achievement in the biomedical field.However,the search for the ideal scaffold is still in its infancy and there are significant challenges to overcome.In the modern era,the scientific community is increasingly turned to natural substances due to their superior biological ability,lower cost,biodegradability,and lower toxicity than synthetic lab-made products.Chitosan is a well-known polysaccharide that has recently garnered a high amount of attention for its biological activities,especially in 3D bone tissue engineering.Chitosan closely matches the native tissues and thus stands out as a popular candidate for bioprinting.This review focuses on the potential of chitosan-based scaffolds for advancements and the drawbacks in bone treatment.Chitosan-based nanocomposites have exhibited strong mechanical strength,water-trapping ability,cellular interaction,and biodegradability.Chitosan derivatives have also encouraged and provided different routes for treatment and enhanced biological activities.3D tailored bioprinting has opened new doors for designing and manufacturing scaffolds with biological,mechanical,and topographical properties.展开更多
Tendon and ligament injuries represent a major orthopedic challenge with limited effective regenerative options.In an original research study by Yang et al de-veloped a tissue engineering approach combining aligned na...Tendon and ligament injuries represent a major orthopedic challenge with limited effective regenerative options.In an original research study by Yang et al de-veloped a tissue engineering approach combining aligned nanofiber scaffolds with cyclic uniaxial stretching to promote tenogenic differentiation in bone marrow-derived mesenchymal stem cells.Their results provide critical insight into how structural and mechanical cues can synergize to generate ligament-like tissue in vitro.This editorial contextualizes their findings within the broader field of ligament regeneration and highlights the translational potential of their strategy.展开更多
The field of bone tissue engineering has experienced an increase in prevalence due to the inherent challenge of the natural regeneration of significant bone deformities.This investigation focused on the preparation of...The field of bone tissue engineering has experienced an increase in prevalence due to the inherent challenge of the natural regeneration of significant bone deformities.This investigation focused on the preparation of Three-Dimensional(3D)-printed Polycaprolactone(PCL)scaffolds with varying proportions of Nanohydroxyapatite(NHA)and Nanoclay(NC),and their physiochemical and biological properties were assessed.The mechanical properties of PCL are satisfactory;however,its hydrophobic nature and long-term degradation hinder its use in scaffold fabrication.NHA and NC have been employed to improve the hydrophilic characteristics,mechanical strength,adhesive properties,biocompatibility,biodegradability,and osteoconductive behavior of PCL.The morphology results demonstrated 3D-printed structures with interconnected rectangular macropores and proper nanoparticle distribution.The sample containing 70 wt%NC showed the highest porosity(65.98±2.54%),leading to an increased degradation rate.The compressive strength ranged from 10.65±1.90 to 84.93±9.93 MPa,which is directly proportional to the compressive strength of cancellous bone(2–12 MPa).The wettability,water uptake,and biodegradability of PCL scaffolds considerably improved as the amount of NC increased.The results of the cellular assays exhibited increased proliferation,viability,and adhesion of MG-63 cells due to the addition of NHA and NC to the scaffolds.Finally,according to the in vitro results,it can be concluded that 3D-printed samples with higher amounts of NC can be regarded as a suitable scaffold for expediting the regeneration process of bone defects.展开更多
Owing to their unique biological effects and physicochemical properties,nanomaterials have garnered substantial attention in the field of bone tissue engineering(BTE),targeting the repair and restoration of impaired b...Owing to their unique biological effects and physicochemical properties,nanomaterials have garnered substantial attention in the field of bone tissue engineering(BTE),targeting the repair and restoration of impaired bone tissue.In recent years,strategies for the design and optimization of nanomaterials through thiolation modification have been widely applied in BTE.This review concisely summarizes the categories of nanomaterials commonly used in BTE and focuses on various strategies for the modification of nanomaterials via thiolation.A multifaceted analysis of the mechanisms by which thiolated nanomaterials enhance nanomaterial-cell interactions,promote drug loading and release,and modulate osteogenic differentiation is presented.Furthermore,this review introduces biomedical applications of thiolated nanomaterials in BTE,including as scaffold components for bone regeneration,coatings for bone implants,and drug delivery systems.Finally,the future perspectives and challenges in the development of this field are discussed.Thiolation modification strategies provide a platform for developing new ideas and methods for designing nanomaterials for BTE and are expected to accelerate the development and clinical translation of novel bone repair materials.展开更多
Biomedical scaffold fabrication has seen advancements in mimicking the native extracellular matrix through intricate three-dimensional(3D)structures conducive to tissue regeneration.Coiled fibrous scaffolds have emerg...Biomedical scaffold fabrication has seen advancements in mimicking the native extracellular matrix through intricate three-dimensional(3D)structures conducive to tissue regeneration.Coiled fibrous scaffolds have emerged as promising substrates owing to their ability to provide unique topographical cues.In this study,coiled poly(ε-caprolactone)(PCL)fibrous bundles were fabricated using an alginate-based composite system,and processed with 3D printing.The unique structure was obtained through the die-swell phenomenon related to the release of residual stresses from the printed strut,thereby transforming aligned PCL fibers into coiled structures.The effects of printing parameters,such as pneumatic pressure and nozzle moving speed,on fiber morphology were investigated to ensure a consistent formation of coiled PCL fibers.The resulting coiled PCL fibrous scaffold demonstrated higher activation of mechanotransduction signaling as well as upregulation of osteogenic-related genes in human adipose stem cells(hASCs),supporting its potential in bone tissue engineering.展开更多
This review article presents a comprehensive overview of emerging technologies in bone tissue engineering(BTE).This rapidly advancing field addresses the challenges of bone defects and injuries beyond traditional trea...This review article presents a comprehensive overview of emerging technologies in bone tissue engineering(BTE).This rapidly advancing field addresses the challenges of bone defects and injuries beyond traditional treatments like autografts and allografts.The study highlights the integration of 3D bioprinting,stem cell therapy,gene therapy,biomaterials,nanotechnology,and computational modeling as transformative approaches in BTE.Developing biomimetic scaffolds,advanced bio-inks,and composite nanomaterials has enhanced seaffold design,improving mechanical properties and biocompatibility.Innovatiohs in gene therapy and bioactive molecule delivery are showcased for their ability to modulate cellular behavior and enhance osteogenesis.Stem cell-based therapies leverage the regenerative potential of mesenchymal stem cells,facilitating tissue integration and functional restoration.Computational tools,including finite element analysis(FEA)and agent-based modelling,aid in the optimization of scaffold design,predicting mechanical responses and biological behaviors.Despite notable progress,signifieant challenges,such as achieving reliable vascularization,sealable manu-facturing of engineered constructs,and effective clinical translation,remain substantial barriers to widespread adoption.Future research efforts focused on refining these technologies are vital for translating innovative strategies into elinical practice,paving the way for personalized regenerative solutions in bone repair.展开更多
Nanofiber scaffold has built a bionic microenvironment for bone marrow mesenchymal stem cells by highly simulating the topological structure of natural extracellular matrix.Its ordered fiber network effectively guides...Nanofiber scaffold has built a bionic microenvironment for bone marrow mesenchymal stem cells by highly simulating the topological structure of natural extracellular matrix.Its ordered fiber network effectively guides the directional migration and spatial arrangement of cells through the mechanical signal transduction mediated by integrin.Surface functionalization can synergistically activate the osteogenic transcription network and significantly enhance the osteogenic differentiation potential of cells.The precise design of scaffold stiffness affects the cell fate choice by regulating the nuclear translocation of mechanical sensitive factors.This triple cooperative strategy of“physical topology-biochemical signal-mechanical microenvironment”effectively overcomes the biological inertia of traditional scaffolds and provides a dynamic and adjustable platform for bone defect repair.Looking forward to the future,breaking through the bottleneck of clinical transformation such as long-term intelligent slow release of functional factors and in situ efficient construction of vascular network is the key to promoting nanofiber scaffolds from basic research to precise bone regeneration treatment.展开更多
Neurovascularization serves as the prerequisite and assurance for fostering neurogenesis after peripheral nerve injury(PNI),not only contributing to the reconstruction of the regenerative neurovascular niche but also ...Neurovascularization serves as the prerequisite and assurance for fostering neurogenesis after peripheral nerve injury(PNI),not only contributing to the reconstruction of the regenerative neurovascular niche but also providing a surface and directionality for Schwann cell(SC)cords migration and axons elongation.Despite the development of nerve tissue engineering techniques has drawn increasing attention to the intervention approach for repairing nerve defects,systematic generalization summary of the efficient intervention to expedite nerve angiogenesis is still scarce.This review delves into the mechanisms by which macrophages within the nerve defect trigger angiogenesis after PNI and elucidates how the newborn vessels support nerve regeneration,and then extracts three major categories of strategies for producing vascularized nerves in vitro and in vivo from them,encompassing(1)in vitro prevascularization,(2)in vivo prevascularization,and(3)stimulation of neurovascularization in situ.Furthermore,we emphasize that the lack of accuracy for structure and spatiotemporal regulation,as well as the operational inconvenience and delayed connection to the host's nerve stumps,have stuck the existing neurovascularization technology in the preclinical stage.The successful design of a future prospective clinical vascularized nerve scaffold should be guided by a comprehensive consideration of these aspects.展开更多
In tissue engineering(TE),tissue-inducing scaffolds are a promising solution for organ and tissue repair owing to their ability to attract stem cells in vivo,thereby inducing endogenous tissue regeneration through top...In tissue engineering(TE),tissue-inducing scaffolds are a promising solution for organ and tissue repair owing to their ability to attract stem cells in vivo,thereby inducing endogenous tissue regeneration through topological cues.An ideal TE scaffold should possess biomimetic cross-scale structures,similar to that of natural extracellular matrices,at the nano-to macro-scale level.Although freeform fabrication of TE scaffolds can be achieved through 3D printing,this method is limited in simultaneously building multiscale structures.To address this challenge,low-temperature fields were adopted in the traditional fabrication processes,such as casting and 3D printing.Ice crystals grow during scaffold fabrication and act as a template to control the nano-and micro-structures.These microstructures can be optimized by adjusting various parameters,such as the direction and magnitude of the low-temperature field.By preserving the macro-features fabricated using traditional methods,additional micro-structures with smaller scales can be incorporated simultaneously,realizing cross-scale structures that provide a better mimic of natural organs and tissues.In this paper,we present a state-of-the-art review of three low-temperature-field-assisted fabrication methods—freeze casting,cryogenic3D printing,and freeze spinning.Fundamental working principles,fabrication setups,processes,and examples of biomedical applications are introduced.The challenges and outlook for low-temperature-assisted fabrication are also discussed.展开更多
Tissue engineering and regenerative medicine is a new interdisciplinary subject integrating life science,material science,engineering technology,and clinical medicine.Over the last ten years,significant advancements h...Tissue engineering and regenerative medicine is a new interdisciplinary subject integrating life science,material science,engineering technology,and clinical medicine.Over the last ten years,significant advancements have been achieved in the study of biomaterials and tissue engineering.Progress in the field of tissue engineering and regenerative medicine can result in optimal tissue regeneration and effective functional reconstruction.Spinal cord injury(SCI)is the most severe complication of spinal trauma and frequently results in significant functional impairments in the lower extremities of the affected segment.Repair of SCI is a medical challenge worldwide.Advancements in tissue engineering theory and technology offer fresh opportunities for addressing SCI,as well as providing new strategies and methodologies to tackle the challenges associated with repairing and reconstructing spinal cord function.This article provides an overview of the latest developments in tissue engineering and SCI repair,focusing on biomaterials,cells,and active factors.It also introduces nine key components related to SCI and proposes innovative approaches for repairing and functionally reconstructing the injured spinal cord.展开更多
Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted t...Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted the important therapeutic potential of Tregs in neurological diseases and tissue repair,emphasizing their multifaceted roles in immune regulation.This review aims to summarize and analyze the mechanisms of action and therapeutic potential of Tregs in relation to neurological diseases and neural regeneration.Beyond their classical immune-regulatory functions,emerging evidence points to non-immune mechanisms of regulatory T cells,particularly their interactions with stem cells and other non-immune cells.These interactions contribute to optimizing the repair microenvironment and promoting tissue repair and nerve regeneration,positioning non-immune pathways as a promising direction for future research.By modulating immune and non-immune cells,including neurons and glia within neural tissues,Tregs have demonstrated remarkable efficacy in enhancing regeneration in the central and peripheral nervous systems.Preclinical studies have revealed that Treg cells interact with neurons,glial cells,and other neural components to mitigate inflammatory damage and support functional recovery.Current mechanistic studies show that Tregs can significantly promote neural repair and functional recovery by regulating inflammatory responses and the local immune microenvironment.However,research on the mechanistic roles of regulatory T cells in other diseases remains limited,highlighting substantial gaps and opportunities for exploration in this field.Laboratory and clinical studies have further advanced the application of regulatory T cells.Technical advances have enabled efficient isolation,ex vivo expansion and functionalization,and adoptive transfer of regulatory T cells,with efficacy validated in animal models.Innovative strategies,including gene editing,cell-free technologies,biomaterial-based recruitment,and in situ delivery have expanded the therapeutic potential of regulatory T cells.Gene editing enables precise functional optimization,while biomaterial and in situ delivery technologies enhance their accumulation and efficacy at target sites.These advancements not only improve the immune-regulatory capacity of regulatory T cells but also significantly enhance their role in tissue repair.By leveraging the pivotal and diverse functions of Tregs in immune modulation and tissue repair,regulatory T cells–based therapies may lead to transformative breakthroughs in the treatment of neurological diseases.展开更多
Bamei pigs,an indigenous Chinese breed,yield meat with a delectable flavor and boast higher carcass fat content compared to commercial breeds,making them a rich food source for humans.However,the differences in lipid ...Bamei pigs,an indigenous Chinese breed,yield meat with a delectable flavor and boast higher carcass fat content compared to commercial breeds,making them a rich food source for humans.However,the differences in lipid and nutrient components between the adipose tissue of Bamei pigs and commercial pigs are still unclear.The study employed UPLC-MS/MS to quantify the composition of lipids and metabolites in the backfat of both Bamei and Large White pigs.A total of 428 lipids and 193 metabolites were significantly different between the 2 groups.Specifically,Bamei pig backfat exhibited altered levels of various lipids and metabolites that may potentially contribute to nutritional and flavor differences,including unsaturated triglycerides,free fatty acids,medium-chain triglycerides,essential amino acids,vitamins and antioxidants,while maintaining reduced cholesterol levels.Furthermore,we delved into the molecular mechanisms underlying these nutritional differences by analyzing significantly different 431 m RNAs and 865 proteins and integrating the regulatory network of protein-metabolite-lipid pathway.Importantly,in the pyruvate metabolic pathway of Bamei pigs,the bioprocess of lactate production was inhibited but the acetyl-Co A production was activated,suggesting the possibility that energy allocation favors the biogenesis of lipid precursors.These findings may contribute to guiding industrial food producers in enhancing the quality of lard at the genetic and molecular levels.展开更多
Lacto-N-neotetraose(LNn T)is a crucial neutral core human milk oligosaccharide(HMO).In this study,we established a LNn T-producing Saccharomyces cerevisiae cell factory through comprehensive metabolic engineering.Spec...Lacto-N-neotetraose(LNn T)is a crucial neutral core human milk oligosaccharide(HMO).In this study,we established a LNn T-producing Saccharomyces cerevisiae cell factory through comprehensive metabolic engineering.Specifically,the de novo biosynthetic pathway of LNn T was assembled by heterologously expressing the lactose permease(lac12)from Kluyveromyces lactis and the glycosyltransferase from Neisseria meningitidis in S.cerevisiae.Subsequently,carbon source regulation based on the glucose-sensitive GAL regulatory system was employed to optimize the expression time of heterologous genes,achieving a production of 15.61 mg/L of LNn T in shake-flask fermentation.In addition,the key rate-limiting steps involved in LNn T synthesis pathway were identified and the corresponding genes were overexpressed to enhance LNn T production,resulting in an 8-fold increase in LNn T titer compared to that of parental strain.To our knowledge,this is the first report on LNn T biosynthesis in S.cerevisiae,opening up the possibility of green production of LNn T using food-safe microorganisms.展开更多
基金support from the National Natural Science Foundation of China(No.82472440)Hubei Provincial Natural Science Foundation of China(No.2023AFB141)+1 种基金the National Medical Products Administration Key Laboratory for Dental Materials(No.PKUSS20240401)the Cross-Research Support Program from Huazhong University of Science and Technology。
文摘The esophagus is a tubular organ essential for maintaining normal eating function in humans.However,the replacement of the esophagus remains challenging in clinical settings.Although tissue engineering scaffolds are a promising alternative solution,their fabrication is difficult due to the complex structure and function of the esophagus.This review describes the existing fabrication methods for esophageal tubular scaffolds,including decellularization,casting,electrospinning,three dimensional(3 D)bioprinting,and pin-frogging.Also discussed are the stimulation cues of the fabricated esophageal tubular scaffold that induce esophageal muscle and epithelial cells.Finally,this review emphasizes three important concerns for esophageal tubular scaffolds:leakage and porosity,elasticity and proliferation of smooth muscle cells,and biocompatibility and structural fidelity of biomaterials.
基金funded by the Israeli Ministry of Innovation,Science and Technology(Grant No.3-11873)the Israel Science Foundation(Grant No.1563/10)+1 种基金the Randy L.and Melvin R.Berlin Family Research Center for Regenerative Medicinethe Gurwin Family Foundation.
文摘Cardiac tissue engineering aims to efficiently replace or repair injured heart tissue using scaffolds,relevant cells,or their combination.While the combination of scaffolds and relevant cells holds the potential to rapidly remuscularize the heart,thereby avoiding the slow process of cell recruitment,the proper ex vivo cellularization of a scaffold poses a substantial challenge.First,proper diffusion of nutrients and oxygen should be provided to the cell-seeded scaffold.Second,to generate a functional tissue construct,cells can benefit from physiological-like conditions.To meet these challenges,we developed a modular bioreactor for the dynamic cellularization of full-thickness cardiac scaffolds under synchronized mechanical and electrical stimuli.In this unique bioreactor system,we designed a cyclic mechanical load that mimics the left ventricle volume inflation,thus achieving a steady stimulus,as well as an electrical stimulus with an action potential profile to mirror the cells’microenvironment and electrical stimuli in the heart.These mechanical and electrical stimuli were synchronized according to cardiac physiology and regulated by constant feedback.When applied to a seeded thick porcine cardiac extracellular matrix(pcECM)scaffold,these stimuli improved the proliferation of mesenchymal stem/stromal cells(MSCs)and induced the formation of a dense tissue-like structure near the scaffold’s surface.Most importantly,after 35 d of cultivation,the MSCs presented the early cardiac progenitor markers Connexin-43 andα-actinin,which were absent in the control cells.Overall,this research developed a new bioreactor system for cellularizing cardiac scaffolds under cardiac-like conditions,aiming to restore a sustainable dynamic living tissue that can bear the essential cardiac excitation–contraction coupling.
文摘Oral and maxillofacial reconstruction represents one of the most complex challenges in plastic and reconstructive surgery,requiring the restoration of both form and function in highly specialized anatomical regions.Traditional strategies,including local flaps and autologous bone grafts,remain fundamental but are limited by donor-site morbidity,tissue availability,and unpredictable outcomes.Recent advances in regenerative medicine have shifted the paradigm from repair to true regeneration,harnessing stem cells,biomaterial scaffolds,and signaling molecules in a synergistic approach.Dental-and craniofacial tissue-derived mesenchymal stem cells,along with adipose-derived stem cells,demonstrate significant potential for alveolar bone repair,periodontal regeneration,and soft tissue augmentation.Innovations in three-dimensional printing and bioactive matrices have enabled precise scaffold design and improved vascularization,thereby enhancing both predictability and esthetic outcomes.This mini review focuses on the synergistic role of stem cells,scaffolds,and signaling molecules in oral and maxillofacial regeneration,with an emphasis on the unique contributions of periodontists.By integrating periodontal biology with reconstructive techniques,a new collaborative framework is emerging to optimize regenerative outcomes.Future research must address clinical translation,large-scale trials,cost-effectiveness,and personalized approaches to fully realize the promise of regenerative surgery.
文摘Tissue engineering and regenera-tive medicine have shown signifi-cant potential for repairing and regenerating damaged tissues and can be used to provide personalized treatment plans,with broad applica-tion prospects.In this special issue,Bin Li’s team outlines the latest advances in minimally invasive implantable biomaterials for bone regeneration and different methods of achieving osteogenesis,with a focus on bioceramics and polymer materials and their applications in bone healing,vertebral augmenta-tion,implant fixation,tumor treatment of bone,and treatment of infections related to bone defects.Xinquan Jiang’s team constructs a novel photo-responsive multifunctional polyetheretherketone(PEEK)-based implant material(sPEEK/BP/E7)through the self-assembly of black phosphorus(BP)nanoplatelets,bioinspired poly-dopamine(PDA),and the biologically active short peptide E7 on sPEEK.The material exhibits effective osteogenic effects and good sterilization performance,providing a new idea for clinical application.
文摘The ability to replicate the microenvironment of the human body through the fabrication of scaffolds is a significant achievement in the biomedical field.However,the search for the ideal scaffold is still in its infancy and there are significant challenges to overcome.In the modern era,the scientific community is increasingly turned to natural substances due to their superior biological ability,lower cost,biodegradability,and lower toxicity than synthetic lab-made products.Chitosan is a well-known polysaccharide that has recently garnered a high amount of attention for its biological activities,especially in 3D bone tissue engineering.Chitosan closely matches the native tissues and thus stands out as a popular candidate for bioprinting.This review focuses on the potential of chitosan-based scaffolds for advancements and the drawbacks in bone treatment.Chitosan-based nanocomposites have exhibited strong mechanical strength,water-trapping ability,cellular interaction,and biodegradability.Chitosan derivatives have also encouraged and provided different routes for treatment and enhanced biological activities.3D tailored bioprinting has opened new doors for designing and manufacturing scaffolds with biological,mechanical,and topographical properties.
基金Supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education,No.NRF-2022R1I1A1A01068652.
文摘Tendon and ligament injuries represent a major orthopedic challenge with limited effective regenerative options.In an original research study by Yang et al de-veloped a tissue engineering approach combining aligned nanofiber scaffolds with cyclic uniaxial stretching to promote tenogenic differentiation in bone marrow-derived mesenchymal stem cells.Their results provide critical insight into how structural and mechanical cues can synergize to generate ligament-like tissue in vitro.This editorial contextualizes their findings within the broader field of ligament regeneration and highlights the translational potential of their strategy.
文摘The field of bone tissue engineering has experienced an increase in prevalence due to the inherent challenge of the natural regeneration of significant bone deformities.This investigation focused on the preparation of Three-Dimensional(3D)-printed Polycaprolactone(PCL)scaffolds with varying proportions of Nanohydroxyapatite(NHA)and Nanoclay(NC),and their physiochemical and biological properties were assessed.The mechanical properties of PCL are satisfactory;however,its hydrophobic nature and long-term degradation hinder its use in scaffold fabrication.NHA and NC have been employed to improve the hydrophilic characteristics,mechanical strength,adhesive properties,biocompatibility,biodegradability,and osteoconductive behavior of PCL.The morphology results demonstrated 3D-printed structures with interconnected rectangular macropores and proper nanoparticle distribution.The sample containing 70 wt%NC showed the highest porosity(65.98±2.54%),leading to an increased degradation rate.The compressive strength ranged from 10.65±1.90 to 84.93±9.93 MPa,which is directly proportional to the compressive strength of cancellous bone(2–12 MPa).The wettability,water uptake,and biodegradability of PCL scaffolds considerably improved as the amount of NC increased.The results of the cellular assays exhibited increased proliferation,viability,and adhesion of MG-63 cells due to the addition of NHA and NC to the scaffolds.Finally,according to the in vitro results,it can be concluded that 3D-printed samples with higher amounts of NC can be regarded as a suitable scaffold for expediting the regeneration process of bone defects.
基金financially supported by the National Natural Science Foundation of China(Nos.52103184 and 8226030956)the National Key Research and Development Program of China(No.2022YFC2407503)+3 种基金Key Project of the Natural Science Basic Research Plan of Shaanxi Province(No.2022JZ43)Natural Science Basic Research Program of Shaanxi Province(No.2024JCYBQN-0874)Medical Research Key Project of Xi'an Science and Technology Bureau(No.2024JH-YXZD-0055)Medical Research Project of Xi'an Science and Technology Bureau(No.22YXYJ0083)
文摘Owing to their unique biological effects and physicochemical properties,nanomaterials have garnered substantial attention in the field of bone tissue engineering(BTE),targeting the repair and restoration of impaired bone tissue.In recent years,strategies for the design and optimization of nanomaterials through thiolation modification have been widely applied in BTE.This review concisely summarizes the categories of nanomaterials commonly used in BTE and focuses on various strategies for the modification of nanomaterials via thiolation.A multifaceted analysis of the mechanisms by which thiolated nanomaterials enhance nanomaterial-cell interactions,promote drug loading and release,and modulate osteogenic differentiation is presented.Furthermore,this review introduces biomedical applications of thiolated nanomaterials in BTE,including as scaffold components for bone regeneration,coatings for bone implants,and drug delivery systems.Finally,the future perspectives and challenges in the development of this field are discussed.Thiolation modification strategies provide a platform for developing new ideas and methods for designing nanomaterials for BTE and are expected to accelerate the development and clinical translation of novel bone repair materials.
基金supported by the‘Korea National Institute of Health’research project(2022ER130502)a grant from by SMC-SKKU Future Convergence Academic Research Program,2024supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(RS-2024-00336758)。
文摘Biomedical scaffold fabrication has seen advancements in mimicking the native extracellular matrix through intricate three-dimensional(3D)structures conducive to tissue regeneration.Coiled fibrous scaffolds have emerged as promising substrates owing to their ability to provide unique topographical cues.In this study,coiled poly(ε-caprolactone)(PCL)fibrous bundles were fabricated using an alginate-based composite system,and processed with 3D printing.The unique structure was obtained through the die-swell phenomenon related to the release of residual stresses from the printed strut,thereby transforming aligned PCL fibers into coiled structures.The effects of printing parameters,such as pneumatic pressure and nozzle moving speed,on fiber morphology were investigated to ensure a consistent formation of coiled PCL fibers.The resulting coiled PCL fibrous scaffold demonstrated higher activation of mechanotransduction signaling as well as upregulation of osteogenic-related genes in human adipose stem cells(hASCs),supporting its potential in bone tissue engineering.
基金the Deanship of Scientific Research at King Khalid University for funding this study through the Large Research Group Project under grant number"RGP 2/365/45".
文摘This review article presents a comprehensive overview of emerging technologies in bone tissue engineering(BTE).This rapidly advancing field addresses the challenges of bone defects and injuries beyond traditional treatments like autografts and allografts.The study highlights the integration of 3D bioprinting,stem cell therapy,gene therapy,biomaterials,nanotechnology,and computational modeling as transformative approaches in BTE.Developing biomimetic scaffolds,advanced bio-inks,and composite nanomaterials has enhanced seaffold design,improving mechanical properties and biocompatibility.Innovatiohs in gene therapy and bioactive molecule delivery are showcased for their ability to modulate cellular behavior and enhance osteogenesis.Stem cell-based therapies leverage the regenerative potential of mesenchymal stem cells,facilitating tissue integration and functional restoration.Computational tools,including finite element analysis(FEA)and agent-based modelling,aid in the optimization of scaffold design,predicting mechanical responses and biological behaviors.Despite notable progress,signifieant challenges,such as achieving reliable vascularization,sealable manu-facturing of engineered constructs,and effective clinical translation,remain substantial barriers to widespread adoption.Future research efforts focused on refining these technologies are vital for translating innovative strategies into elinical practice,paving the way for personalized regenerative solutions in bone repair.
文摘Nanofiber scaffold has built a bionic microenvironment for bone marrow mesenchymal stem cells by highly simulating the topological structure of natural extracellular matrix.Its ordered fiber network effectively guides the directional migration and spatial arrangement of cells through the mechanical signal transduction mediated by integrin.Surface functionalization can synergistically activate the osteogenic transcription network and significantly enhance the osteogenic differentiation potential of cells.The precise design of scaffold stiffness affects the cell fate choice by regulating the nuclear translocation of mechanical sensitive factors.This triple cooperative strategy of“physical topology-biochemical signal-mechanical microenvironment”effectively overcomes the biological inertia of traditional scaffolds and provides a dynamic and adjustable platform for bone defect repair.Looking forward to the future,breaking through the bottleneck of clinical transformation such as long-term intelligent slow release of functional factors and in situ efficient construction of vascular network is the key to promoting nanofiber scaffolds from basic research to precise bone regeneration treatment.
基金financially supported by the following programs:National Key Research and Development Program of China(No.2023YFB3813003)National Natural Science Foundation of China(Nos.82430031,82122014,82071085)+1 种基金Zhejiang Provincial Natural Science Foundation of China(No.LR21H140001)the Central Universities(No.2022FZZX01-33)。
文摘Neurovascularization serves as the prerequisite and assurance for fostering neurogenesis after peripheral nerve injury(PNI),not only contributing to the reconstruction of the regenerative neurovascular niche but also providing a surface and directionality for Schwann cell(SC)cords migration and axons elongation.Despite the development of nerve tissue engineering techniques has drawn increasing attention to the intervention approach for repairing nerve defects,systematic generalization summary of the efficient intervention to expedite nerve angiogenesis is still scarce.This review delves into the mechanisms by which macrophages within the nerve defect trigger angiogenesis after PNI and elucidates how the newborn vessels support nerve regeneration,and then extracts three major categories of strategies for producing vascularized nerves in vitro and in vivo from them,encompassing(1)in vitro prevascularization,(2)in vivo prevascularization,and(3)stimulation of neurovascularization in situ.Furthermore,we emphasize that the lack of accuracy for structure and spatiotemporal regulation,as well as the operational inconvenience and delayed connection to the host's nerve stumps,have stuck the existing neurovascularization technology in the preclinical stage.The successful design of a future prospective clinical vascularized nerve scaffold should be guided by a comprehensive consideration of these aspects.
基金National Natural Science Foundation Council of China(Grant No.52305359)Hubei Provincial Natural Science Foundation of China(Grant No.2023AFB141)National Medical Products Administration Key Laboratory for Dental Materials(PKUSS20240401)。
文摘In tissue engineering(TE),tissue-inducing scaffolds are a promising solution for organ and tissue repair owing to their ability to attract stem cells in vivo,thereby inducing endogenous tissue regeneration through topological cues.An ideal TE scaffold should possess biomimetic cross-scale structures,similar to that of natural extracellular matrices,at the nano-to macro-scale level.Although freeform fabrication of TE scaffolds can be achieved through 3D printing,this method is limited in simultaneously building multiscale structures.To address this challenge,low-temperature fields were adopted in the traditional fabrication processes,such as casting and 3D printing.Ice crystals grow during scaffold fabrication and act as a template to control the nano-and micro-structures.These microstructures can be optimized by adjusting various parameters,such as the direction and magnitude of the low-temperature field.By preserving the macro-features fabricated using traditional methods,additional micro-structures with smaller scales can be incorporated simultaneously,realizing cross-scale structures that provide a better mimic of natural organs and tissues.In this paper,we present a state-of-the-art review of three low-temperature-field-assisted fabrication methods—freeze casting,cryogenic3D printing,and freeze spinning.Fundamental working principles,fabrication setups,processes,and examples of biomedical applications are introduced.The challenges and outlook for low-temperature-assisted fabrication are also discussed.
基金supported by grants from the National Natural Science Foundation of China(92368207)the Chinese Academy of Engineering(2023-SBZD-11)the Natural Science Foundation of Jiangsu Province(BK20232023).
文摘Tissue engineering and regenerative medicine is a new interdisciplinary subject integrating life science,material science,engineering technology,and clinical medicine.Over the last ten years,significant advancements have been achieved in the study of biomaterials and tissue engineering.Progress in the field of tissue engineering and regenerative medicine can result in optimal tissue regeneration and effective functional reconstruction.Spinal cord injury(SCI)is the most severe complication of spinal trauma and frequently results in significant functional impairments in the lower extremities of the affected segment.Repair of SCI is a medical challenge worldwide.Advancements in tissue engineering theory and technology offer fresh opportunities for addressing SCI,as well as providing new strategies and methodologies to tackle the challenges associated with repairing and reconstructing spinal cord function.This article provides an overview of the latest developments in tissue engineering and SCI repair,focusing on biomaterials,cells,and active factors.It also introduces nine key components related to SCI and proposes innovative approaches for repairing and functionally reconstructing the injured spinal cord.
基金supported by the National Natural Science Foundation of China,Nos.32271389,31900987(both to PY)the Natural Science Foundation of Jiangsu Province,No.BK20230608(to JJ)。
文摘Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted the important therapeutic potential of Tregs in neurological diseases and tissue repair,emphasizing their multifaceted roles in immune regulation.This review aims to summarize and analyze the mechanisms of action and therapeutic potential of Tregs in relation to neurological diseases and neural regeneration.Beyond their classical immune-regulatory functions,emerging evidence points to non-immune mechanisms of regulatory T cells,particularly their interactions with stem cells and other non-immune cells.These interactions contribute to optimizing the repair microenvironment and promoting tissue repair and nerve regeneration,positioning non-immune pathways as a promising direction for future research.By modulating immune and non-immune cells,including neurons and glia within neural tissues,Tregs have demonstrated remarkable efficacy in enhancing regeneration in the central and peripheral nervous systems.Preclinical studies have revealed that Treg cells interact with neurons,glial cells,and other neural components to mitigate inflammatory damage and support functional recovery.Current mechanistic studies show that Tregs can significantly promote neural repair and functional recovery by regulating inflammatory responses and the local immune microenvironment.However,research on the mechanistic roles of regulatory T cells in other diseases remains limited,highlighting substantial gaps and opportunities for exploration in this field.Laboratory and clinical studies have further advanced the application of regulatory T cells.Technical advances have enabled efficient isolation,ex vivo expansion and functionalization,and adoptive transfer of regulatory T cells,with efficacy validated in animal models.Innovative strategies,including gene editing,cell-free technologies,biomaterial-based recruitment,and in situ delivery have expanded the therapeutic potential of regulatory T cells.Gene editing enables precise functional optimization,while biomaterial and in situ delivery technologies enhance their accumulation and efficacy at target sites.These advancements not only improve the immune-regulatory capacity of regulatory T cells but also significantly enhance their role in tissue repair.By leveraging the pivotal and diverse functions of Tregs in immune modulation and tissue repair,regulatory T cells–based therapies may lead to transformative breakthroughs in the treatment of neurological diseases.
基金supported by the National Key Research and Development Program of China(2021YFF1000602)the National Natural Science Foundations(32202642)the earmarked fund for CARS-35-PIG.
文摘Bamei pigs,an indigenous Chinese breed,yield meat with a delectable flavor and boast higher carcass fat content compared to commercial breeds,making them a rich food source for humans.However,the differences in lipid and nutrient components between the adipose tissue of Bamei pigs and commercial pigs are still unclear.The study employed UPLC-MS/MS to quantify the composition of lipids and metabolites in the backfat of both Bamei and Large White pigs.A total of 428 lipids and 193 metabolites were significantly different between the 2 groups.Specifically,Bamei pig backfat exhibited altered levels of various lipids and metabolites that may potentially contribute to nutritional and flavor differences,including unsaturated triglycerides,free fatty acids,medium-chain triglycerides,essential amino acids,vitamins and antioxidants,while maintaining reduced cholesterol levels.Furthermore,we delved into the molecular mechanisms underlying these nutritional differences by analyzing significantly different 431 m RNAs and 865 proteins and integrating the regulatory network of protein-metabolite-lipid pathway.Importantly,in the pyruvate metabolic pathway of Bamei pigs,the bioprocess of lactate production was inhibited but the acetyl-Co A production was activated,suggesting the possibility that energy allocation favors the biogenesis of lipid precursors.These findings may contribute to guiding industrial food producers in enhancing the quality of lard at the genetic and molecular levels.
基金funded by the National Key Research and Development Program of China(2022YFF1100300)National Natural Science Foundation of China(22108097)+2 种基金Key Research and Development Program of Jiangsu Province(BE2022850)Taihu Innovation-Leading Talent of Wuxi City(1026010241230040)Cross-Integration Innovation Funding of SFST(SFST2023-KY-10).
文摘Lacto-N-neotetraose(LNn T)is a crucial neutral core human milk oligosaccharide(HMO).In this study,we established a LNn T-producing Saccharomyces cerevisiae cell factory through comprehensive metabolic engineering.Specifically,the de novo biosynthetic pathway of LNn T was assembled by heterologously expressing the lactose permease(lac12)from Kluyveromyces lactis and the glycosyltransferase from Neisseria meningitidis in S.cerevisiae.Subsequently,carbon source regulation based on the glucose-sensitive GAL regulatory system was employed to optimize the expression time of heterologous genes,achieving a production of 15.61 mg/L of LNn T in shake-flask fermentation.In addition,the key rate-limiting steps involved in LNn T synthesis pathway were identified and the corresponding genes were overexpressed to enhance LNn T production,resulting in an 8-fold increase in LNn T titer compared to that of parental strain.To our knowledge,this is the first report on LNn T biosynthesis in S.cerevisiae,opening up the possibility of green production of LNn T using food-safe microorganisms.
