3D printing,also called additive manufacturing,is being used increasingly in tissue engineering.However,the printing accuracy remains limited,making it difficult to prepare a tissue engineering scaffold with high prec...3D printing,also called additive manufacturing,is being used increasingly in tissue engineering.However,the printing accuracy remains limited,making it difficult to prepare a tissue engineering scaffold with high precision and high porosity.Melt electrowriting(MEW)technology is based on extrusion printing,in which an extruded material is pulled by the action of an electric field,thereby reducing the fiber diameter and improving the printing accuracy.However,MEW technology imposes high requirements on the material properties,and therefore,few printing materials are currently available for use in this process.The present study investigates the characteristics and molding conditions of polycaprolactone,a commonly used printing material,as well as other materials such as poly(lactic-co-glycolic acid),poly(ethylene glycol)diacrylate/polyethylene oxide,gelatin methacrylate,and hyaluronic acid methacrylate for MEW applications,and develops new and suitable inks for MEW that will provide more and better choices for constructing a bioactive scaffold in future tissue engineering research.Experiments suggest that a printing ink should have low electrical conductivity,suitable viscosity,and high curing speed for realizing successful printing.展开更多
The dual role of macrophages in the healing process depends on macrophage ability to polarize into phenotypes that can propagate inflammation or exert anti-inflammatory and tissue-remodeling functions.Controlling scaf...The dual role of macrophages in the healing process depends on macrophage ability to polarize into phenotypes that can propagate inflammation or exert anti-inflammatory and tissue-remodeling functions.Controlling scaf-fold geometry has been proposed as a strategy to influence macrophage behavior and favor the positive host response to implants.Here,we fabricated Polycaprolactone(PCL)scaffolds by Melt Electrowriting(MEW)to investigate the ability of scaffold architecture to modulate macrophage polarization.Primary human macrophages unpolarized(M0)or polarized into M1,M2a,and M2c phenotypes were cultured on PCL films and MEW scaffolds with pore geometries(square,triangle,and rhombus grid)characterized by different angles.M0,M2a,and M2c macrophages wrapped along the fibers,while M1 macrophages formed clusters with rounded cells.Cell bridges were formed only for angles up to 90◦.No relevant differences were found among PCL films and 3D scaffolds in terms of surface markers.CD206 and CD163 were highly expressed by M2a and M2c macrophages,with M2a macrophages presenting also high levels of CD86.M1 macrophages expressed moderate levels of all markers.The rhombus architecture promoted an increased release by M2a macrophages of IL10,IL13,and sCD163 compared to PCL films.The proangiogenic factor IL18 was also upregulated by the rhombus configuration in M0 and M2a macrophages compared to PCL films.The interesting findings obtained for the rhombus architecture represent a starting point for the design of scaffolds able to modulate macrophage phenotype,prompting investigations addressed to verify their ability to facilitate the healing process in vivo.展开更多
Recently,the high incidence of oral mucosal defects and the subsequent functional impairments have attracted widespread attention.Controlling scaffold geometry pattern has been proposed as a strategy to promote cell b...Recently,the high incidence of oral mucosal defects and the subsequent functional impairments have attracted widespread attention.Controlling scaffold geometry pattern has been proposed as a strategy to promote cell behavior and facilitate soft tissue repair.In this study,we innovatively construct an integrated dual-layer heterogeneous polycaprolactone(PCL)scaffold using melt electrowriting(MEW)technology.The outer layer was disordered,while the inner layer featured oriented fiber patterns:parallel(P-par),rhombic(P-rhomb),and square(P-sq).Our findings revealed that the P-rhomb and P-sq scaffolds exhibited superior surface wettability,roughness,and tensile strength compared to the pure disordered PCL scaffolds(P)and P-par.Compared to the commercial collagen membranes,the outer layer of PCL can effectively inhibit bacterial adhesion and biofilm formation.Furthermore,the P-rhomb and P-sq groups demonstrated higher gene and protein expression levels related to cell adhesion and cell migration rates than did the P and P-par groups.Among them,P-sq plays an important role in inducing the differentiation of gingival fibroblasts into myofibroblasts rich inα-smooth muscle actin(α-SMA).Additionally,P-sq could reduce inflammation,promote epithelial regeneration,and accelerate wound healing when used in full-thickness oral mucosal defects in rabbits.Overall,the integrated dual-layer heterogeneous PCL scaffold fabricated by MEW technology effectively inhibited bacterial adhesion and guided tissue regeneration,offering advantages for clinical translation and large-scale production.This promising material holds important potential for treating full-thickness mucosal defects in a bacteria-rich oral environments.展开更多
Fabrication of functional scaffolds for tissue engineering and regenerative medicine applications requires material systems with precise control over cellular performance.3D printing is a powerful technique to create ...Fabrication of functional scaffolds for tissue engineering and regenerative medicine applications requires material systems with precise control over cellular performance.3D printing is a powerful technique to create highly complex and multicomponent structures with well-defined architecture and composition.In this review paper,we explore extrusion-based 3D printing methods(EBP,i.e.,Near Field Electrospinning(NFES),Melt Electrowriting(MEW),Fused Deposition Modeling(FDM),and extrusion bioprinting)in terms of their ability to produce scaffolds with bio-instructive properties.These material systems provide spatio-temporal guidance for cells,allowing controlled tissue regeneration and maturation.Multiple physical and biochemical cues introduced to the EBP scaffolds are evaluated in their ability to direct cell alignment,proliferation,differentiation,specific ECM production,and tissue maturation.We indicate that the cues have different impacts depending on the material system,cell type used,or coexistence of multiple cues.Therefore,they must be carefully chosen based on the targeted application.We propose future directions in bio-instructive materials development,including such concepts as metamaterials,hybrid living materials,and 4D printing.The review gathers the knowledge essential for designing new materials with a controlled cellular response,fabrication of advanced engineered tissue,and developing a better understanding of cell biology,especially in response to the biomaterial.展开更多
Melt electrowriting(MEW)is a solvent-free(i.e.,no volatile chemicals),a high-resolution three-dimensional(3D)printing method that enables the fabrication of semi-flexible structures with rigid polymers.Despite its adv...Melt electrowriting(MEW)is a solvent-free(i.e.,no volatile chemicals),a high-resolution three-dimensional(3D)printing method that enables the fabrication of semi-flexible structures with rigid polymers.Despite its advantages,the MEW pro-cess is sensitive to changes in printing parameters(e.g.,voltage,printing pressure,and temperature),which can causefluid column breakage,jet lag,and/orfiber pulsing,ultimately deteriorating the resolution and printing quality.In spite of the commonly used error-and-trial method to determine the most suitable parameters,here,we present a machine learning(ML)-enabled image analysis-based method for determining the optimum MEW printing parameters through an easy-to-use graph-ical user interface(GUI).We trainedfive different ML algorithms using 168 MEW 3D print samples,among which the Gaussian process regression ML model yielded 93%accuracy of the variability in the dependent variable,0.12329 on root mean square error for the validation set and 0.015201 mean square error in predicting line thickness.Integration of ML with a control feedback loop and MEW can reduce the error-and-trial steps prior to the 3D printing process,decreasing the printing time(i.e.,increasing the overall throughput of MEW)and material waste(i.e.,improving the cost-effectiveness of MEW).Moreover,embedding a trained ML model with the feedback control system in a GUI facilitates a more straightforward use of ML-based optimization techniques in the industrial section(i.e.,for users with no ML skills).展开更多
Periodontitis is a chronic inflammatory condition that often causes serious damage to tooth-supporting tissues.The limited successful outcomes of clinically available approaches underscore the need for therapeutics th...Periodontitis is a chronic inflammatory condition that often causes serious damage to tooth-supporting tissues.The limited successful outcomes of clinically available approaches underscore the need for therapeutics that cannot only provide structural guidance to cells but can also modulate the local immune response.Here,three-dimensional melt electrowritten(i.e.,poly(ε-caprolactone))scaffolds with tissue-specific attributes were engineered to guide differentiation of human-derived periodontal ligament stem cells(hPDLSCs)and mediate macrophage polarization.The investigated tissue-specific scaffold attributes comprised fiber morphology(aligned vs.random)and highly-ordered architectures with distinct strand spacings(small 250μm and large 500μm).Macrophages exhibited an elongated morphology in aligned and highly-ordered scaffolds,while maintaining their round-shape on randomly-oriented fibrous scaffolds.Expressions of periostin and IL-10 were more pronounced on the aligned and highly-ordered scaffolds.While hPDLSCs on the scaffolds with 500μm strand spacing show higher expression of osteogenic marker(Runx2)over 21 days,cells on randomly-oriented fibrous scaffolds showed upregulation of M1 markers.In an orthotopic mandibular fenestration defect model,findings revealed that the tissue-specific scaffolds(i.e.,aligned fibers for periodontal ligament and highly-ordered 500μm strand spacing fluorinated calcium phosphate[F/CaP]-coated fibers for bone)could enhance the mimicking of regeneration of natural periodontal tissues.展开更多
基金the National Key R&D Program of China(Nos.2018YFB1105600 and 2018YFA0703000)the National Natural Science Foundation of China(No.81802131)the China Postdoctoral Science Foundation(No.2019T120347)。
文摘3D printing,also called additive manufacturing,is being used increasingly in tissue engineering.However,the printing accuracy remains limited,making it difficult to prepare a tissue engineering scaffold with high precision and high porosity.Melt electrowriting(MEW)technology is based on extrusion printing,in which an extruded material is pulled by the action of an electric field,thereby reducing the fiber diameter and improving the printing accuracy.However,MEW technology imposes high requirements on the material properties,and therefore,few printing materials are currently available for use in this process.The present study investigates the characteristics and molding conditions of polycaprolactone,a commonly used printing material,as well as other materials such as poly(lactic-co-glycolic acid),poly(ethylene glycol)diacrylate/polyethylene oxide,gelatin methacrylate,and hyaluronic acid methacrylate for MEW applications,and develops new and suitable inks for MEW that will provide more and better choices for constructing a bioactive scaffold in future tissue engineering research.Experiments suggest that a printing ink should have low electrical conductivity,suitable viscosity,and high curing speed for realizing successful printing.
基金Italian Ministry of Health(Ricerca Corrente)Interreg NWE BONE Project(NWE497),and the project NeuroBeta with project number 15900 of the VENI research program which is financed by the Dutch Research Council(NWO).
文摘The dual role of macrophages in the healing process depends on macrophage ability to polarize into phenotypes that can propagate inflammation or exert anti-inflammatory and tissue-remodeling functions.Controlling scaf-fold geometry has been proposed as a strategy to influence macrophage behavior and favor the positive host response to implants.Here,we fabricated Polycaprolactone(PCL)scaffolds by Melt Electrowriting(MEW)to investigate the ability of scaffold architecture to modulate macrophage polarization.Primary human macrophages unpolarized(M0)or polarized into M1,M2a,and M2c phenotypes were cultured on PCL films and MEW scaffolds with pore geometries(square,triangle,and rhombus grid)characterized by different angles.M0,M2a,and M2c macrophages wrapped along the fibers,while M1 macrophages formed clusters with rounded cells.Cell bridges were formed only for angles up to 90◦.No relevant differences were found among PCL films and 3D scaffolds in terms of surface markers.CD206 and CD163 were highly expressed by M2a and M2c macrophages,with M2a macrophages presenting also high levels of CD86.M1 macrophages expressed moderate levels of all markers.The rhombus architecture promoted an increased release by M2a macrophages of IL10,IL13,and sCD163 compared to PCL films.The proangiogenic factor IL18 was also upregulated by the rhombus configuration in M0 and M2a macrophages compared to PCL films.The interesting findings obtained for the rhombus architecture represent a starting point for the design of scaffolds able to modulate macrophage phenotype,prompting investigations addressed to verify their ability to facilitate the healing process in vivo.
基金funded by the Key Research and Development Program of Zhejiang Province(2021C03059 and 2024C03081)the National Natural Science Foundation of China(81801024)the Research and Development Project of Stomatology Hospital Zhejiang University School of Medicine(RD2023JXXK01).
文摘Recently,the high incidence of oral mucosal defects and the subsequent functional impairments have attracted widespread attention.Controlling scaffold geometry pattern has been proposed as a strategy to promote cell behavior and facilitate soft tissue repair.In this study,we innovatively construct an integrated dual-layer heterogeneous polycaprolactone(PCL)scaffold using melt electrowriting(MEW)technology.The outer layer was disordered,while the inner layer featured oriented fiber patterns:parallel(P-par),rhombic(P-rhomb),and square(P-sq).Our findings revealed that the P-rhomb and P-sq scaffolds exhibited superior surface wettability,roughness,and tensile strength compared to the pure disordered PCL scaffolds(P)and P-par.Compared to the commercial collagen membranes,the outer layer of PCL can effectively inhibit bacterial adhesion and biofilm formation.Furthermore,the P-rhomb and P-sq groups demonstrated higher gene and protein expression levels related to cell adhesion and cell migration rates than did the P and P-par groups.Among them,P-sq plays an important role in inducing the differentiation of gingival fibroblasts into myofibroblasts rich inα-smooth muscle actin(α-SMA).Additionally,P-sq could reduce inflammation,promote epithelial regeneration,and accelerate wound healing when used in full-thickness oral mucosal defects in rabbits.Overall,the integrated dual-layer heterogeneous PCL scaffold fabricated by MEW technology effectively inhibited bacterial adhesion and guided tissue regeneration,offering advantages for clinical translation and large-scale production.This promising material holds important potential for treating full-thickness mucosal defects in a bacteria-rich oral environments.
基金financial support from the Polish National Agency for Academic Exchange(NAWA,Polish Returns grant no.PPN/PPO/2019/1/00004/U/0001)acknowledges the National Science Centre,Poland(NCN,OPUS grant no.2020/37/B/ST5/00743)the Dutch Research Council(NWO,Veni grant no.VI.Veni.192.148)。
文摘Fabrication of functional scaffolds for tissue engineering and regenerative medicine applications requires material systems with precise control over cellular performance.3D printing is a powerful technique to create highly complex and multicomponent structures with well-defined architecture and composition.In this review paper,we explore extrusion-based 3D printing methods(EBP,i.e.,Near Field Electrospinning(NFES),Melt Electrowriting(MEW),Fused Deposition Modeling(FDM),and extrusion bioprinting)in terms of their ability to produce scaffolds with bio-instructive properties.These material systems provide spatio-temporal guidance for cells,allowing controlled tissue regeneration and maturation.Multiple physical and biochemical cues introduced to the EBP scaffolds are evaluated in their ability to direct cell alignment,proliferation,differentiation,specific ECM production,and tissue maturation.We indicate that the cues have different impacts depending on the material system,cell type used,or coexistence of multiple cues.Therefore,they must be carefully chosen based on the targeted application.We propose future directions in bio-instructive materials development,including such concepts as metamaterials,hybrid living materials,and 4D printing.The review gathers the knowledge essential for designing new materials with a controlled cellular response,fabrication of advanced engineered tissue,and developing a better understanding of cell biology,especially in response to the biomaterial.
基金Tubitak 2232 International Fellowship for Outstanding Researchers Award,Grant/Award Number:118C391Alexander von Humboldt Research Fellowship for Experienced Researchers+4 种基金Marie Skłodowska-Curie Individual Fellowship,Grant/Award Number:101003361Royal Academy Newton-KatipÇelebi Transforming Systems,Grant/Award Number:120N019Science Academy’s Young Scientist Awards ProgramOutstanding Young Scientists AwardsBilim Kahramanlari Dernegi the Young Scientist Award。
文摘Melt electrowriting(MEW)is a solvent-free(i.e.,no volatile chemicals),a high-resolution three-dimensional(3D)printing method that enables the fabrication of semi-flexible structures with rigid polymers.Despite its advantages,the MEW pro-cess is sensitive to changes in printing parameters(e.g.,voltage,printing pressure,and temperature),which can causefluid column breakage,jet lag,and/orfiber pulsing,ultimately deteriorating the resolution and printing quality.In spite of the commonly used error-and-trial method to determine the most suitable parameters,here,we present a machine learning(ML)-enabled image analysis-based method for determining the optimum MEW printing parameters through an easy-to-use graph-ical user interface(GUI).We trainedfive different ML algorithms using 168 MEW 3D print samples,among which the Gaussian process regression ML model yielded 93%accuracy of the variability in the dependent variable,0.12329 on root mean square error for the validation set and 0.015201 mean square error in predicting line thickness.Integration of ML with a control feedback loop and MEW can reduce the error-and-trial steps prior to the 3D printing process,decreasing the printing time(i.e.,increasing the overall throughput of MEW)and material waste(i.e.,improving the cost-effectiveness of MEW).Moreover,embedding a trained ML model with the feedback control system in a GUI facilitates a more straightforward use of ML-based optimization techniques in the industrial section(i.e.,for users with no ML skills).
基金the National Institutes of Health(NIH-National Institute of Dental and Craniofacial Research,grants K08DE023552,R01DE026578)。
文摘Periodontitis is a chronic inflammatory condition that often causes serious damage to tooth-supporting tissues.The limited successful outcomes of clinically available approaches underscore the need for therapeutics that cannot only provide structural guidance to cells but can also modulate the local immune response.Here,three-dimensional melt electrowritten(i.e.,poly(ε-caprolactone))scaffolds with tissue-specific attributes were engineered to guide differentiation of human-derived periodontal ligament stem cells(hPDLSCs)and mediate macrophage polarization.The investigated tissue-specific scaffold attributes comprised fiber morphology(aligned vs.random)and highly-ordered architectures with distinct strand spacings(small 250μm and large 500μm).Macrophages exhibited an elongated morphology in aligned and highly-ordered scaffolds,while maintaining their round-shape on randomly-oriented fibrous scaffolds.Expressions of periostin and IL-10 were more pronounced on the aligned and highly-ordered scaffolds.While hPDLSCs on the scaffolds with 500μm strand spacing show higher expression of osteogenic marker(Runx2)over 21 days,cells on randomly-oriented fibrous scaffolds showed upregulation of M1 markers.In an orthotopic mandibular fenestration defect model,findings revealed that the tissue-specific scaffolds(i.e.,aligned fibers for periodontal ligament and highly-ordered 500μm strand spacing fluorinated calcium phosphate[F/CaP]-coated fibers for bone)could enhance the mimicking of regeneration of natural periodontal tissues.
