Spinal cord injuries（SCIs） are debilitating conditions for which no effective treatment currently exists. The damage of neural tissue causes disruption of neural tracts and neuron loss in the spinal cord. Stem cell ...Spinal cord injuries（SCIs） are debilitating conditions for which no effective treatment currently exists. The damage of neural tissue causes disruption of neural tracts and neuron loss in the spinal cord. Stem cell replacement offers a solution for SCI treatment by providing a source of therapeutic cells for neural function restoration. Induced pluripotent stem cells（i PSCs） have been investigated as a potential type of stem cell for such therapies. Transplantation of i PSCs has been shown to be effective in restoring function after SCIs in animal models while they circumvent ethical and immunological concerns produced by other stem cell types. Another approach for the treatment of SCI involves the graft of a bioscaffold at the site of injury to create a microenvironment that enhances cellular viability and guides the growing axons. Studies suggest that a combination of these two treatment methods could have a synergistic effect on functional recovery post-neural injury. While much progress has been made, more research is needed before clinical trials are possible. This review highlights recent advancements using i PSCs and bioscaffolds for treatment of SCI.展开更多
Prevailing tissue degeneration caused by musculoskeletal maladies poses a great demand on bioscaffolds,which are artificial,biocompatible structures implanted into human bodies with appropriate mechanical properties.R...Prevailing tissue degeneration caused by musculoskeletal maladies poses a great demand on bioscaffolds,which are artificial,biocompatible structures implanted into human bodies with appropriate mechanical properties.Recent advances in additive manufacturing,i.e.,3D printing,facilitated the fabrication of bioscaffolds with unprecedented geometrical complexity and size flexibility and allowed for the fabrication of topologies that would not have been achieved otherwise.In our work,we explored the effect of porosity on themechanical properties of a periodic cellular structure.The structure was derived from the mathematically created triply periodic minimal surface(TPMS),namely the Sheet-Diamond topology.First,we employed a series of software including MathMod,Meshmixer,Netfabb and Cura to design the model.Then,we utilized additive manufacturing technology to fabricate the cellular structures with designated scale.Finally,we performed compressive testing to deduce the mechanical properties of each cellular structure.Results showed that,in comparison with the highporosity group,the yield strength of the low-porosity group was 3 times higher,and the modulus was 2.5 times larger.Our experiments revealed a specific relationship between porosity and Young’s modulus of PLA-made Sheet-Diamond TPMS structure.Moreover,it was observed that the high-and low-porosity structures failed through distinctive mechanisms,with the former breaking down via buckling and the latter via micro-fracturing.展开更多
Injury to central nervous system(CNS)tissues in adult mam-mals often leads to neuronal loss,scarring,and permanently lost neurologic functions,and this default healing response is increasingly linked to a pro-inflamma...Injury to central nervous system(CNS)tissues in adult mam-mals often leads to neuronal loss,scarring,and permanently lost neurologic functions,and this default healing response is increasingly linked to a pro-inflammatory innate immune response.Extracellular matrix(ECM)technology can reduce inflammation,while increasing functional tissue remodeling in various tissues and organs,including the CNS.展开更多
Skin aging,a complex physiological process characterized by alterations in skin structure and function,seriously affects human life.Collagen holds considerable potential in aging skin treatment,while animal-derived co...Skin aging,a complex physiological process characterized by alterations in skin structure and function,seriously affects human life.Collagen holds considerable potential in aging skin treatment,while animal-derived collagen poses risks of pathogen transmission.Self-assembled peptides have garnered increasing attention in creating collagen mimetic materials;however,previous reported self-assembled peptides rely on vulnerable non-covalent interactions or lack the capability of controlling morphology and incorporating functional motifs,limiting their ability to mimic collagen structure and function.We have herein created a controllable tyrosine-rich triblock peptide system capable of self-assembling into robust collagen mimetic bioscaffolds for rejuvenating aging skin.Through ruthenium-mediated crosslinking,these peptides self-assemble into well-defined nanospheres or collagen-mimetic scaffolds,precisely regulated by the triple-helical structure and tyrosine distribution.The self-assembled collagen mimetic scaffolds exhibit outstanding resistances to various solvents and pH conditions.The integrin-binding motif has been incorporated into the triple helical block without disrupting their assembly,while endowing them with superior bioactivities,effectively promoting cell adhesion and proliferation.In vivo studies demonstrated their efficacy in treating photoaging skin by accelerating collagen regeneration and activating fibroblasts.The self-assembled tyrosine-rich triblock peptides represent a versatile system for creating robust collagen mimetic biomaterials,providing great potential in skin rejuvenation and tissue regeneration.展开更多
Neural injuries can be induced by various neurological disorders and traumas,such as brain and spinal cord injuries,cerebrovascular diseases,and neurodegeneration.Due to the designable physicochemical properties,bioma...Neural injuries can be induced by various neurological disorders and traumas,such as brain and spinal cord injuries,cerebrovascular diseases,and neurodegeneration.Due to the designable physicochemical properties,biomaterials are applied for various purposes in neural repair,including promoting axonal regeneration,reducing glial scar formation,delivering drugs,and providing temporary mechanical support to the injured tissue.They need to match the extracellular matrix(ECM)environment,support threedimensional(3D)cell growth,repair the cellular microenvironment,mimic the tissue's biomechanical forces,and possess biodegradability and plasticity suitable for local intracavity applications.Meanwhile,functionalized biomaterials have been conducted to mimic the structural components of cellular ecological niches and the specific functions of the ECM.They can be engineered to carry a variety of bioactive components,such as stem cells and extracellular vesicles,which are used in neuroscience-related tissue engineering.Researchers also have developed biomaterial-based brain-like organs for high-throughput drug screening and pathological mechanistic studies.This review will discuss the interactions between biomaterials and cells,as well as the advances in neural injuries and engineered microtissues.展开更多
The demand for artificial organs has greatly increased because of various aging-associated diseases and the wide need for organ transplants.A recent trend in tissue engineering is the precise reconstruction of tissues...The demand for artificial organs has greatly increased because of various aging-associated diseases and the wide need for organ transplants.A recent trend in tissue engineering is the precise reconstruction of tissues by the growth of cells adhering to bioscaffolds,which are three-dimensional(3D)structures that guide tissue and organ formation.Bioscaffolds used to fabricate bionic tissues should be able to not only guide cell growth but also regulate cell behaviors.Common regulation methods include biophysical and biochemical stimulations.Biophysical stimulation cues include matrix hardness,external stress and strain,surface topology,and electromagnetic field and concentration,whereas biochemical stimulation cues include growth factors,proteins,kinases,and magnetic nanoparticles.This review discusses bioink preparation,3D bioprinting(including extrusion-based,inkjet,and ultraviolet-assisted 3D bioprinting),and regulation of cell behaviors.In particular,it provides an overview of state-of-the-art methods and devices for regulating cell growth and tissue formation and the effects of biophysical and biochemical stimulations on cell behaviors.In addition,the fabrication of bioscaffolds embedded with regulatory modules for biomimetic tissue preparation is explained.Finally,challenges in cell growth regulation and future research directions are presented.展开更多
The construction of biological scaffolds in vitro plays an important role in regenerative engineering,which has always been the focus of research.The application of scaffold materials combined with cells/bioactive fac...The construction of biological scaffolds in vitro plays an important role in regenerative engineering,which has always been the focus of research.The application of scaffold materials combined with cells/bioactive factors is considered to have great potential for tissue regeneration.Various strategies have been used for constructing biological scaffolds,including electrospinning/spraying,direct laser writing,solvent casting,and microfluidic technology.Among them,considering the advantages of the safety,low cost,and highly controllable process-ing characteristics,microfluidic technology has become a promising method for the construction of biological scaffolds.This review overviews the recent research progress of microfluidic bioscaffolds for regenerative engi-neering.Firstly,we introduce some typical natural polymers which are widely used to construct bioscaffolds.Then,the bioscaffolds with different structures templated by microfluidic droplets and fibers are described.Fur-therly,we talk about the different applications of microfluidic bioscaffolds in wound healing,drug delivery,bone regeneration,and nerve regeneration.Finally,the challenges and future prospects of the development of microfluidic bioscaffolds for regenerative engineering are discussed.展开更多
AIM:To assess the effects of bile and pancreatic juice on structural and mechanical resistance of extracellular matrices(ECMs) in vitro.METHODS:Small-intestinal submucosa(SIS),porcine dermal matrix(PDM),porcine perica...AIM:To assess the effects of bile and pancreatic juice on structural and mechanical resistance of extracellular matrices(ECMs) in vitro.METHODS:Small-intestinal submucosa(SIS),porcine dermal matrix(PDM),porcine pericardial matrix(PPM) and bovine pericardial matrix(BPM) were incubated in human bile and pancreatic juice in vitro.ECMs were examined by macroscopic observation,scanning electron microscopy(SEM) and testing of mechanical resistance.RESULTS:PDM dissolved within 4 d after exposure to bile or pancreatic juice.SIS,PPM and PDM retained their integrity for > 60 d when incubated in either digestive juice.The effect of bile was found to be far more detrimental to mechanical stability than pancreatic juice in all tested materials.In SIS,the loss of mechanical stability after incubation in either of the digestive secretions was less distinct than in PPM and BPM [mFmax 4.01/14.27 N(SIS) vs 2.08/5.23 N(PPM) vs 1.48/7.89 N(BPM)].In SIS,the extent of structural damage revealed by SEM was more evident in bile than in pancreatic juice.In PPM and BPM,structural damage was comparable in both media.CONCLUSION:PDM is less suitable for support of gastrointestinal healing.Besides SIS,PPM and BPM should also be evaluated experimentally for gastrointestinal indications.展开更多
文摘Spinal cord injuries（SCIs） are debilitating conditions for which no effective treatment currently exists. The damage of neural tissue causes disruption of neural tracts and neuron loss in the spinal cord. Stem cell replacement offers a solution for SCI treatment by providing a source of therapeutic cells for neural function restoration. Induced pluripotent stem cells（i PSCs） have been investigated as a potential type of stem cell for such therapies. Transplantation of i PSCs has been shown to be effective in restoring function after SCIs in animal models while they circumvent ethical and immunological concerns produced by other stem cell types. Another approach for the treatment of SCI involves the graft of a bioscaffold at the site of injury to create a microenvironment that enhances cellular viability and guides the growing axons. Studies suggest that a combination of these two treatment methods could have a synergistic effect on functional recovery post-neural injury. While much progress has been made, more research is needed before clinical trials are possible. This review highlights recent advancements using i PSCs and bioscaffolds for treatment of SCI.
文摘Prevailing tissue degeneration caused by musculoskeletal maladies poses a great demand on bioscaffolds,which are artificial,biocompatible structures implanted into human bodies with appropriate mechanical properties.Recent advances in additive manufacturing,i.e.,3D printing,facilitated the fabrication of bioscaffolds with unprecedented geometrical complexity and size flexibility and allowed for the fabrication of topologies that would not have been achieved otherwise.In our work,we explored the effect of porosity on themechanical properties of a periodic cellular structure.The structure was derived from the mathematically created triply periodic minimal surface(TPMS),namely the Sheet-Diamond topology.First,we employed a series of software including MathMod,Meshmixer,Netfabb and Cura to design the model.Then,we utilized additive manufacturing technology to fabricate the cellular structures with designated scale.Finally,we performed compressive testing to deduce the mechanical properties of each cellular structure.Results showed that,in comparison with the highporosity group,the yield strength of the low-porosity group was 3 times higher,and the modulus was 2.5 times larger.Our experiments revealed a specific relationship between porosity and Young’s modulus of PLA-made Sheet-Diamond TPMS structure.Moreover,it was observed that the high-and low-porosity structures failed through distinctive mechanisms,with the former breaking down via buckling and the latter via micro-fracturing.
文摘Injury to central nervous system(CNS)tissues in adult mam-mals often leads to neuronal loss,scarring,and permanently lost neurologic functions,and this default healing response is increasingly linked to a pro-inflammatory innate immune response.Extracellular matrix(ECM)technology can reduce inflammation,while increasing functional tissue remodeling in various tissues and organs,including the CNS.
基金supported by grants from the National Natural Science Foundation of China(grant nos.22074057,22205089 and 22304066)the Natural Science Foundation of Gansu Province(grant nos.20YF3FA025 and 23JRRA1096)+1 种基金China Postdoctoral Science Foundation(2022M711449)Lanzhou Science and Technology Program Project(2023-3-31).
文摘Skin aging,a complex physiological process characterized by alterations in skin structure and function,seriously affects human life.Collagen holds considerable potential in aging skin treatment,while animal-derived collagen poses risks of pathogen transmission.Self-assembled peptides have garnered increasing attention in creating collagen mimetic materials;however,previous reported self-assembled peptides rely on vulnerable non-covalent interactions or lack the capability of controlling morphology and incorporating functional motifs,limiting their ability to mimic collagen structure and function.We have herein created a controllable tyrosine-rich triblock peptide system capable of self-assembling into robust collagen mimetic bioscaffolds for rejuvenating aging skin.Through ruthenium-mediated crosslinking,these peptides self-assemble into well-defined nanospheres or collagen-mimetic scaffolds,precisely regulated by the triple-helical structure and tyrosine distribution.The self-assembled collagen mimetic scaffolds exhibit outstanding resistances to various solvents and pH conditions.The integrin-binding motif has been incorporated into the triple helical block without disrupting their assembly,while endowing them with superior bioactivities,effectively promoting cell adhesion and proliferation.In vivo studies demonstrated their efficacy in treating photoaging skin by accelerating collagen regeneration and activating fibroblasts.The self-assembled tyrosine-rich triblock peptides represent a versatile system for creating robust collagen mimetic biomaterials,providing great potential in skin rejuvenation and tissue regeneration.
基金supported by the National Natural Science Foundation of China(No.82273487)the Young Medical Scientists Training Program(No.21QNPY051)the Shanghai Integration Achievement Program(No.2022-RH17)。
文摘Neural injuries can be induced by various neurological disorders and traumas,such as brain and spinal cord injuries,cerebrovascular diseases,and neurodegeneration.Due to the designable physicochemical properties,biomaterials are applied for various purposes in neural repair,including promoting axonal regeneration,reducing glial scar formation,delivering drugs,and providing temporary mechanical support to the injured tissue.They need to match the extracellular matrix(ECM)environment,support threedimensional(3D)cell growth,repair the cellular microenvironment,mimic the tissue's biomechanical forces,and possess biodegradability and plasticity suitable for local intracavity applications.Meanwhile,functionalized biomaterials have been conducted to mimic the structural components of cellular ecological niches and the specific functions of the ECM.They can be engineered to carry a variety of bioactive components,such as stem cells and extracellular vesicles,which are used in neuroscience-related tissue engineering.Researchers also have developed biomaterial-based brain-like organs for high-throughput drug screening and pathological mechanistic studies.This review will discuss the interactions between biomaterials and cells,as well as the advances in neural injuries and engineered microtissues.
基金supported by the Innovative Public Service Center of High-End Manufacturing Technology for Technical Service of High-Tech Zone,Qiqihar,China.
文摘The demand for artificial organs has greatly increased because of various aging-associated diseases and the wide need for organ transplants.A recent trend in tissue engineering is the precise reconstruction of tissues by the growth of cells adhering to bioscaffolds,which are three-dimensional(3D)structures that guide tissue and organ formation.Bioscaffolds used to fabricate bionic tissues should be able to not only guide cell growth but also regulate cell behaviors.Common regulation methods include biophysical and biochemical stimulations.Biophysical stimulation cues include matrix hardness,external stress and strain,surface topology,and electromagnetic field and concentration,whereas biochemical stimulation cues include growth factors,proteins,kinases,and magnetic nanoparticles.This review discusses bioink preparation,3D bioprinting(including extrusion-based,inkjet,and ultraviolet-assisted 3D bioprinting),and regulation of cell behaviors.In particular,it provides an overview of state-of-the-art methods and devices for regulating cell growth and tissue formation and the effects of biophysical and biochemical stimulations on cell behaviors.In addition,the fabrication of bioscaffolds embedded with regulatory modules for biomimetic tissue preparation is explained.Finally,challenges in cell growth regulation and future research directions are presented.
基金supported by the National Natural Science Founda-tion of China(Grant No.22002061)the Fundamental Research Funds for the Central Universities(Grant No.KJQN202138)+4 种基金the Natural Sci-ence Foundation of Jiangsu Province(Grant No.BK20200551)the Jiangsu Agricultural Science and Technology Innovation Fund[Grant No.CX(20)3051]the Jiangsu Provincial Double-Innovation Doctor Pro-gram(Grant No.JSSCBS20210283)the Postdoctoral Science Founda-tion of China(Grant No.2021M691615)the Postdoctoral Science Foundation of Jiangsu Province(Grant No.2021K011A).
文摘The construction of biological scaffolds in vitro plays an important role in regenerative engineering,which has always been the focus of research.The application of scaffold materials combined with cells/bioactive factors is considered to have great potential for tissue regeneration.Various strategies have been used for constructing biological scaffolds,including electrospinning/spraying,direct laser writing,solvent casting,and microfluidic technology.Among them,considering the advantages of the safety,low cost,and highly controllable process-ing characteristics,microfluidic technology has become a promising method for the construction of biological scaffolds.This review overviews the recent research progress of microfluidic bioscaffolds for regenerative engi-neering.Firstly,we introduce some typical natural polymers which are widely used to construct bioscaffolds.Then,the bioscaffolds with different structures templated by microfluidic droplets and fibers are described.Fur-therly,we talk about the different applications of microfluidic bioscaffolds in wound healing,drug delivery,bone regeneration,and nerve regeneration.Finally,the challenges and future prospects of the development of microfluidic bioscaffolds for regenerative engineering are discussed.
文摘AIM:To assess the effects of bile and pancreatic juice on structural and mechanical resistance of extracellular matrices(ECMs) in vitro.METHODS:Small-intestinal submucosa(SIS),porcine dermal matrix(PDM),porcine pericardial matrix(PPM) and bovine pericardial matrix(BPM) were incubated in human bile and pancreatic juice in vitro.ECMs were examined by macroscopic observation,scanning electron microscopy(SEM) and testing of mechanical resistance.RESULTS:PDM dissolved within 4 d after exposure to bile or pancreatic juice.SIS,PPM and PDM retained their integrity for > 60 d when incubated in either digestive juice.The effect of bile was found to be far more detrimental to mechanical stability than pancreatic juice in all tested materials.In SIS,the loss of mechanical stability after incubation in either of the digestive secretions was less distinct than in PPM and BPM [mFmax 4.01/14.27 N(SIS) vs 2.08/5.23 N(PPM) vs 1.48/7.89 N(BPM)].In SIS,the extent of structural damage revealed by SEM was more evident in bile than in pancreatic juice.In PPM and BPM,structural damage was comparable in both media.CONCLUSION:PDM is less suitable for support of gastrointestinal healing.Besides SIS,PPM and BPM should also be evaluated experimentally for gastrointestinal indications.
