Methods in molecular biology (Clifton, N.J.)Farah Qaderi, U Kaicheng, Yeganeh Farsi, Junhan Zhao, Nima Saeidi
Two-dimensional (2D) culture systems are powerful in vitro tools that have revolutionized the study of intestinal stem cell biology. These culture systems derived from mouse intestinal and colonic epithelia enable the modeling of tissue architecture, barrier function, and disease mechanisms under physiologically relevant conditions. This protocol details methods for isolating and maintaining mouse intestinal crypts as 2D monolayers. Monolayers are established via enzymatic dissociation and seeding onto ECM-functionalized hydrogels. This protocol also describes a deep learning pipeline that performs virtual fluorescent staining of label-free phase-contrast images of live organoids. This protocol enables the reproducible generation and computational analysis of murine intestinal epithelial cultures for studies in epithelial biology, drug testing, and disease modeling. This integrated system is designed for facilitating high-throughput imaging, immunolabeling, and functional analysis, expanding its use in regenerative medicine, tissue engineering, and gastrointestinal research.
Methods in molecular biology (Clifton, N.J.)Marianna Cosentino, Desiree Genovese, Antonio Musarò
The development of three-dimensional (3D) tissue constructs that accurately replicate the morphology and function of native tissues is critical for advancing tissue engineering and regenerative medicine. Two primary strategies are currently employed: scaffold-based and scaffold-free approaches. Both aim to reproduce a biomimetic microenvironment that supports cell-cell and cell-matrix interactions, enabling the formation of functional tissues. To circumvent the immunological and toxicological limitations related to the use of exogenous scaffold materials, scaffold-free tissue engineering has emerged as a promising alternative. This method utilizes multicellular aggregates that fuse into cohesive structures while naturally producing extracellular matrix (ECM). Harnessing the intrinsic capacity of cells to self-organize and assemble into sheets enhances cell-cell connectivity and promotes spontaneous ECM remodeling, facilitating the formation of scaffold-free tissues. This study outlines the methodology for generating a 3D skeletal muscle tissue in vitro without the use of scaffolds. Here, we describe key analytical techniques, including flow cytometry, immunofluorescence, and histological staining, used to evaluate tissue functionality in physiological and pathological contexts. The proposed protocols enable the creation of a mouse skeletal muscle model suitable for drug screening and testing, considering its advantages and limitations. Furthermore, the integration of patient-derived biopsies or induced pluripotent stem cells (iPSCs) establishes a basis for personalized therapeutic applications in clinical settings.
Development (Cambridge, England)Delia Luisa Rodríguez-Bustos, Luis Eduardo Sánchez-Cisneros, Luis Daniel Ríos-Barrera
This article discusses the preprinted work of Cuenca and colleagues ( Cuenca et al., 2026 preprint) as well as that of Balasubramaniam and team ( Balasubramaniam et al., 2026 preprint). As preprints, these works have not yet undergone peer review.
Science advancesSiqi Wang, Xiaoyu Wang, Shuai Fu, Claire Senger, Jacob Pfund, Menka Jain, Reika Katsumata, Jun Yao
Harnessing bio-origin resources for energy conversion offers a promising pathway toward energy sustainability matched to biosystems, addressing a fundamental limitation in powering bio-integrated electronics. However, existing approaches by integrating harvesters onto continuous substrates follow a "centralized" paradigm that differs markedly from the inherently distributed energy conversion found in living tissues, limiting both biocompatibility and scalability. We demonstrate a distributed harvesting strategy by integrating individual harvesting units within a mesh network that closely mimics the structural and mechanical properties of biological tissues. This architecture enables seamless embedding within in vitro cardiac tissue to form a bio-hybridization with cellular-scale intimacy across both device and substrate, transcending conventional approaches limited to a surface contact. This strategy achieves effective energy density more than an order of magnitude higher than that of existing approaches based on the centralized paradigm. While the concept is currently demonstrated in an in vitro cardiac system for converting biomechanical energy, the approach can provide a generalizable framework for integrating diverse energy-harvesting modalities and offers a pathway toward in vivo biohybrid systems.
Science advancesKevin L Shores, Xin D Gao, David R Liu, George A Truskey
In vitro models of vascular disease have focused primarily on the pathophysiology of smooth muscle cell (SMC) or endothelial cell (EC). Adventitial fibroblasts can contribute to disease progression, but their specific influence is not well understood in different disease contexts. To elucidate fibroblast's impact on vascular pathology, we developed trilayer tissue-engineered blood vessels (TEBVs) with SMCs, ECs, and fibroblasts. We modeled atherosclerosis in the accelerated aging disease, Hutchinson-Gilford progeria syndrome (HGPS). HGPS fibroblasts substantially elevated several features of the vascular pathology. Correcting the HGPS-associated mutation using base editing returned many disease characteristics to healthy levels. By generating TEBVs with different combinations of vascular cells with or without the HGPS mutation, we found that fibroblasts contributed to extracellular matrix dysregulation and fibrotic signaling, SMCs to collagen accumulation, and ECs to inflammation. These results clarify the poorly understood influence of fibroblasts in progression of HGPS vascular pathology. The trilayer TEBV model could enable further mechanistic insights or therapeutic discovery for other vascular diseases.
Science advancesYuanhang Xiang, Binqi Wei, Yueyang Sun, Weifeng Liu, Hui Zhao, Xiaojie Qin, Changfeng Zhu, Xinchun Li, Fan Yang
Tempo-spatially controlled culture and assembly of cellular spheroids are fundamental in engineering tissue-like assembloids for scalable application, yet remain a technical challenge. Here, we show self-buoyant culture of cell spheroids and programmable assembly of multi-spheroid by microbubbles in a high-throughput, external field-free and miniaturized format. This approach allows one-step engineering of biocompatible cell-adhesive buoyancy interface that lifts the self-adaptive levitation growth of reliable one-drop-one-spheroid in an array without requiring any external fields. Using this self-floating spheroidal microarray, we find that a facile droplet 'kiss' facilitates the buoyancy-driven ultrafast transfer (∼1 s) of spheroids between top-down adjacent droplets, thus achieving rapid spheroid relocation, media exchange, and drug administration in parallel. Such a self-buoyant approach allows programmable horizontal/vertical bioassembly and enhanced fusion of homo/heterogeneous multi-spheroids into different "buoyantoid" patterns via sequential flash transfer along droplet array. This self-powered design provides a promising tool to enable mass production and smart manipulation of encoded assembloids for precision medicine, tissue engineering and high-throughput drug screening.
BiofabricationOliver Kopinski-Grünwald, Corinna Barella, Anastasiia Budaeva, Jason A Burdick, Nathan Carpentier, Justin Cooper-White, Nikolas Galensowske, Antonia Georgopoul…
Biofabrication is a multidisciplinary field that integrates diverse technologies to create three-dimensional structures composed of living cells, biomaterials, and other biological components. One of its main goals is the realization of functional tissue constructs with hierarchical architectures, as observed in native biological tissues, for applications in tissue engineering and regenerative medicine, as well as forin vitromodelling. Given its multidisciplinary nature, continued collaboration among experts from various scientific and technological disciplines remains essential to address the challenges ahead and to achieve the ambitious objectives of this rapidly advancing field. Reflecting on the progress made since the first bioprinting attempts, one can only envision the achievements that biofabrication may accomplish in the coming decades. Symposia such as the Alpine winter school for Biofabrication, bring together leading experts and early-stage researchers who collectively shape the future of the discipline through innovation and discussion. During the 2025 edition of the winter school, participants exchanged knowledge on current advances, challenges, and future perspectives in biofabrication. Guided by experts in this field, early-stage researchers discussed and summarized their views on five key topics: (i) the future of devices and technology in biofabrication, (ii) current trends and opportunities in material development, (iii) impact on society, ethics, and communication, (iv) applications and clinical translation, and (v) education and skillsets required for successful research. Their perspectives summarized here, address critical questions about future methodology, material development, and technological improvements that will continue to shape the evolution of biofabrication. Furthermore, aspects such as the impact on society, as well as the required skillset and education for future scientists working in the field are discussed.
BACKGROUND: Bone diseases, including osteoporosis, arthritis, and spinal disorders, pose significant global health challenges, especially with an aging population. Traditional treatment methods often fall short in addressing the complexity and variability of these conditions. Three-dimensional (3D) printing technology has emerged as a transformative tool in orthopedics, enabling the creation of patient-specific implants, surgical guides, and anatomical models that enhance precision and personalization in treatment. Despite its potential, challenges such as regulatory barriers, high costs, and limited scalability hinder widespread clinical adoption. OBJECTIVE: This study aims to conduct a bibliometric analysis of the research landscape surrounding the application of 3D printing in bone diseases, identifying emerging trends, influential contributors, and knowledge gaps to inform future research and clinical translation. METHODS: This study analyzed publications on 3D printing in bone diseases from 2005 to 2024 using data from the Web of Science Core Collection. We performed co-occurrence mapping, keyword clustering, and citation analysis using CiteSpace, R Bibliometrix, and GraphPad Prism. We examined trends in research output, collaboration among countries and institutions, and thematic developments. RESULTS: Between 2005 and 2024, 544 relevant publications were identified, with a rapid growth phase observed post-2016. China and the USA emerged as leading contributors, collectively accounting for over 50% of global research output. Key application areas included scaffolds for bone regeneration, tissue engineering integrating stem cell technology, and drug delivery systems. Keyword analysis highlighted "scaffolds," "tissue engineering," and "additive manufacturing" as central themes. Despite progress, challenges in standardization, material biocompatibility, and cost-effective manufacturing persist. CONCLUSION: 3D printing is reshaping research and clinical applications in bone diseases by offering innovative solutions for bone regeneration, surgical precision, and personalized treatment. Overcoming challenges such as regulatory complexities, scalability, and interdisciplinary collaboration is critical for full clinical integration. Future research should focus on advancing bioprinting techniques, optimizing hybrid manufacturing, and leveraging artificial intelligence -driven design for enhanced patient-specific outcomes.
Science advancesSherina Malkani, Olivia Prado, Inkyung Kang, Kelly R Stevens
Engineered tissues offer great promise for therapeutic organ repair. Yet, biofabrication of organ-scale tissues can take hours or days for large constructs with geometric complexity, during which living cells in the construct lack vascular support. To address this, we developed an approach to accelerate biofabrication by embedding microreservoirs of evacuation reagents throughout geometrically patterned sacrificial agents. We call this approach Suspended Particles for Omnidirectional Template Sacrifice (SPOTS). We show that microparticles can serve as both structural impurities as well as depots for dissolution agents within sacrificial materials, both of which facilitate accelerated degradation of sacrificial materials and vascular templates. We used SPOTS to produce branched vascular networks in engineered tissue constructs. These networks support perfusion and endothelialization, improve the viability of human cells embedded in the construct, and support phenotype and function of human hepatocytes in the surrounding matrix. By accelerating biofabrication processes, SPOTS thus addresses a critical remaining challenge hindering translation of engineered tissues.
Journal of biomedical materials research. Part AParvin Mohammadi, Mina Habibizadeh, Zhila Izadi, Kamran Mansouri, Mahmoudreza Moradi
Urethral stricture remains a challenging clinical condition, particularly in patients with long or complex defects where suitable donor tissue is limited. Tissue engineering offers a promising alternative through the development of biomimetic scaffolds capable of restoring urethral structure and function. In this study, we fabricated a sandwich nanofibrous scaffold based on polyglycolic acid (PGA) and decellularized urethral extracellular matrix (uECM) using a sandwich design (uECM/PGA/uECM) and compared it with PGA and mix (PGA-uECM) scaffolds. Successful decellularization was confirmed by histological and molecular analyses, demonstrating effective removal of cellular components while preserving ECM architecture. Structural characterization revealed high porosity, enhanced hydrophilicity, favorable swelling behavior, and controlled degradation in ECM-containing scaffolds. The uECM/PGA/uECM construct exhibited superior mechanical strength while maintaining suitable elasticity for urethral applications. Biological evaluation showed significantly improved endothelial cell adhesion, cell viability, and migration in ECM-integrated scaffolds compared with PGA alone. In vivo implantation demonstrated excellent biocompatibility, absence of adverse inflammatory responses, and evident neovascularization. Overall, the sandwich uECM/PGA/uECM scaffold combines mechanical stability with bioactive functionality, highlighting its potential as a promising candidate for urethral tissue regeneration.
Journal of biomedical materials research. Part AAlex S Kermani, Andrea C Filler, J Kent Leach
Cultivated meat (CM) seeks to decouple meat production from animal agriculture, but producing structured products that consumers recognize as whole-cut meat remains both difficult and central to the field's ambitions. Scaffolds are key to this goal, providing architecture, cell-adhesion sites, and instructive cues required to organize cells into texturally mimetic tissue. To date, CM scaffold research has largely borrowed from tissue engineering, which optimizes for therapeutic function and does not account for the constraints that define a food product: edibility, low cost, and large scale. Here, we review scalable scaffold materials and fabrication methods for structured CM through this food-first lens. We identify relevant elements of the native muscle microenvironment and assess how these characteristics have been recapitulated. We then evaluate the major classes of scaffold materials, including those of synthetic, animal, plant, fungal, and microbial origin, as well as waste-stream-derived materials, and compare their biological suitability and scalability. We organize fabrication methods by the biological function they address: cell expansion, alignment, bulk structure, and multi-material assembly, treating mass transport as a constraint that cuts across these methods rather than a separate function. Throughout, we emphasize that consumer perception of meat quality is driven by architecture rather than physiological function, and throughput and cost determine commercial viability. We conclude by identifying critical gaps that warrant scientific focus to bring structured CM to market.
Biotechnology journalNiayesh Najafi, Kevin Babakhan Vartanian, Tony Eskandar, Edgmin Rostomian, Finosh G Thankam
PURPOSE: Adhesive hydrogels (AHs) are promising biomaterials for cardiac tissue engineering due to their injectability, ability to adhere to wet tissue, and structural similarity to the native extracellular matrix (ECM). This review evaluates the perspectives, opportunities, and challenges associated with AHs in cardiac tissue repair and functional recovery. Adhesion is achieved through chemical mechanisms including Schiff base reactions, Michael addition, and enzymatic crosslinking, as well as physical interactions including hydrogen bonding, host-guest complexation, and catechol-based binding. These mechanisms support integration with the dynamic and mechanically active cardiac surface ensuring the localized and sustained delivery of cells/therapeutics. METHODS: Peer reviewed articles were identified through searches of PubMed and Embase using terms related to "adhesive hydrogels," "bioadhesion," and "cardiac tissue engineering." Studies were included based on relevance to adhesion chemistry, mechanical integration, in vivo cardiac performance, and translational outcomes. RESULTS: Recent reports demonstrated improvements in ventricular remodeling, neovascularization, and scar size reduction, while early-stage clinical trials report safety and potential functional benefits of AH-based cardiac applications. CONCLUSION: Continued progress in material design, biocompatibility, and clinical delivery approaches is essential for translating adhesive hydrogels into routine therapies for heart management.
BiofabricationZarya Rajestari, Christopher T Clark, Quinton Smith, Lawrence Kulinsky
The fabrication of biomimetic tubular architectures within hydrogel-based tissue constructs remains a major barrier to advancing scalable tissue engineering and organoid systems. Here, we present a rapid and modular strategy for engineering hollow, perfusable channels within gelatin methacryloyl (GelMA) hydrogels using dissolvable calcium alginate fibers fabricated by an immersed microfluidic spinning method. This approach enables stochastic deposition of sacrificial fibers within a broad range of total construct sizes, creating tortuous and coiled architectures directly within soft hydrogel matrices. Upon UV crosslinking, the alginate fibers are dissolved using a cytocompatible calcium-chelator solution, yielding continuous, open cavities. Across a range of GelMA concentrations, the method produced stable channels compatible with cell-laden constructs. Viability assays with human dermal fibroblasts (HDF) confirmed >90% cell survival in regions adjacent to the channel within the diffusion limit, ranging from 700µm in the softest 5% GelMA to 70µm in the stiffest 15% GelMA, following fabrication and fiber dissolution. Furthermore, epithelial seeding of tortuous channels yielded perfusable structures with tight junctional function, demonstrating the method's potential to generate biologically relevant epithelial architectures. This accessible, equipment-light platform provides a versatile route for integrating microchannel networks into hydrogel systems for regenerative andin vitromodeling applications.
Lasers in medical scienceVladimir Galdino Sabino, Fernanda Ginani, Talita da Silva Grimke, Carlos Eduardo Bezerra de Moura, Hugo Alexandre de Oliveira Rocha, Paulo Henrique de Souza Pi…
This study aimed to evaluate the short-term effects of photobiomodulation (PBM) on stem cells from human exfoliated deciduous teeth (SHEDs) cultured on electrospun polylactic acid (PLA) microfibrous scaffolds. The scaffolds were characterized by scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. SHEDs were seeded onto the scaffold surface and assigned to three groups: nonirradiated control (C), L0.5 (0.5 J/cm²), and L1 (1.0 J/cm²). PBM was delivered with a 660 nm diode laser at 0 and 48 h after the initial irradiation time point. Cell metabolic activity was assessed at 24, 48, and 72 h using the Alamar Blue assay. Qualitative viable-cell distribution and cell-scaffold interactions were evaluated by Live/Dead staining and scanning electron microscopy, respectively. SHEDs remained viable on the PLA microfibrous scaffold and showed increasing metabolic activity over time. Compared with the control group, L1 presented higher Alamar Blue reduction values at 48 and 72 h, with the highest metabolic activity observed at 72 h. Live/Dead images showed qualitatively more extensive viable-cell colonization of the scaffold surface in the irradiated groups, without an apparent increase in dead-cell staining. Scanning electron microscopy revealed SHED adhesion to the microfibrous scaffold in all groups and qualitatively more extensive cell coverage after irradiation, particularly in L1. Electrospun PLA microfibrous scaffolds supported short-term SHED culture, and PBM at 1.0 J/cm² increased SHED metabolic activity and was associated with favorable qualitative cell-scaffold interactions. These findings provide preliminary support for PBM as an adjunctive biophysical strategy for improving early cellular responses in SHED-seeded electrospun PLA scaffolds.
BiofabricationJerry Chen, Javier A Alvarado, Claire Robertson, Salma Ramirez, William F Hynes, Monica L Moya, Lindy K Jang
Three-dimensional (3D) printing of hydrogels has advanced rapidly across numerous disciplines, including tissue engineering, medical devices, and biotechnology, enabling applications including cell scaffolds, drug delivery systems, and biosensors. However, the rapid fabrication of multi-layered complex hydrogel structures remains a significant challenge when employing traditional 3D printing methods. In this study, we demonstrated a four-dimensional printing (4D) approach that leveraged the shape-morphing properties of multi-layered hydrogels to efficiently create complex and fine featured structures using a digital projection stereolithographic printer. We optimized various poly(ethylene glycol) (PEG)-thiol-ene resin formulations and printing parameters to develop seven 3D printable resins that exhibited a wide range of volumetric swelling ratios, from 1.21 to 10.75, and a corresponding decrease in Young's modulus, from 98.10 kPa to 0.35 kPa. By varying the combinations of hydrogel layers with distinct swelling ratios and Young's moduli in the printed bilayer constructs, we could create curved structures with controllable bending angles ranging from 139° to 479° upon immersion in phosphate-buffered saline. We further demonstrated that the bending angles of these bilayer structures could be predicted using Timoshenko beam equation for lower-to-moderate swelling mismatch systems, while higher-swelling mismatch systems exhibited larger prediction deviations. By spatially patterning these resins within flat, multi-layered prints, we achieved programmed actuation into complex, doubly curved geometries such as domes and saddles. Furthermore, our approach enabled the fabrication of complex, nature-inspired curvilinear structures such as flowers, octopuses, and butterflies. This shape-morphing hydrogel printing method significantly reduces fabrication time, eliminates the need for structural supports, and maintains high precision and reproducibility. Overall, our technique offers a rapid and versatile strategy for producing small-scale, complex, multi-layered hydrogel structures, reducing print time from over an hour to just minutes. This approach shows potential utility in future bioengineering and soft robotics applications.
BiofabricationYuexi Zhuang, Miriam Seiti, Karen Libberecht, Tim Vangansewinkel, Ivo Lambrichts, Eleonora Ferraris
Conductive and biocompatible (micro)structures have attracted considerable interest in bioelectronic systems, tissue engineering, and cell-instructive interfaces. However, the reliable fabrication of bioconductive microstructures with high resolution, excellent electrical performance, and good biocompatibility remains a current biofabrication challenge, which requires the synergistic advancement of functionalised materials and their related production process. In this study, Aerosol jet® printing (AJ®P) is proposed as a promising direct writing approach towards fabricating bioconductive microstructures. A systematic investigation was conducted on gold nanoparticles (AuNPs) conductive patterns, focusing on the effects of key AJ®P parameters, including nozzle diameter, carrier gas flow rate (CG), and focus ratio (Rf), on printed linewidth (Lw).CGwas identified as the dominant factor governingLw, with a strong coupling effect betweenCGandRf. By optimising printing parameters, a minimumLwof 16.3 ± 0.2μm was achieved with high reproducibility. Electrical characterisation revealed that increasing the number of printed layers significantly reduced resistance, reaching a minimum of 6.8 ± 0.4 Ω due to enhanced microstructural connectivity. The biocompatibility of AuNPs coatings was evaluated by culturing human Dental Pulp Stem cells differentiated Schwann cells (hDPSC-SCs) on the coating. The results demonstrated that hDPSC-SCs displayed good adhesion, proliferation and maintained their phenotype. On AJ®P-fabricated 100/160μm AuNPs micropatterns, the cell density on the AuNPs tracks was about 4 times higher than that on the adjacent glass regions, indicating a pronounced preferential adhesion of hDPSC-SCs to the conductive microtracks. Furthermore, on the 40/160μm AuNP micropatterns, up to 93% of hDPSC-SCs were aligned along the printing direction, demonstrating a strong contact-guidance effect. These results demonstrate that the AuNPs microtracks provided effective guidance, promoting both cell adhesion and alignment. Overall, this study demonstrates the feasibility of AJ®P for the high-resolution fabrication of bioconductive AuNP micropatterns. The findings provide a manufacturing foundation for the application of metal-based conductive microstructures in bioelectronic interfaces and cell-instructive culture systems, and offer valuable insights for the future development of more advanced neural tissue engineering platforms.
BiofabricationSara Lipari, Pasquale Sacco, Eleonora Marsich, Ana Svetić, Nathalie Dusserre, Malou Lea, Maurizio Romano, Loredana Casalis, Hugo de Oliveira, Ivan Donati
Dental caries represents one of the most prevalent oral diseases worldwide, and conventional treatments rely on the use of inert restorative materials. Yet, restoration failure rates remain frequent, as currentin vitrotesting platforms fail to reproduce the complexity of native dental tissues. Here, we present a bioprinted dual-mechanical dentin-pulp platform generated using a methacrylated alginate (ALMA)-based biomaterial ink that can be either single or dual crosslinked (i.e. SC and DC models). These platforms, which differ in terms of stiffness and viscoelasticity, were developed to probe how biophysical cues govern cell-specific functions. When bioprinted within these matrices, HDPSCs-derived odontoblasts showed upregulation of lineage-specific markers and tissue mineralization within the DC models. In contrast, Human Umbilical Vein Endothelial Cells developed a more complex and interconnected vessel-like network within the SC constructs. By integrating both compartments within a single platform, we propose anin vitrodentin-pulp model that mimics the mechanical heterogeneity of native dental tissues.
Tendon ruptures heal poorly due to hypocellularity, disorganized extracellular matrix (ECM), and inadequate mechanical loading. Current scaffold-stem cell strategies lack integration of dynamic mechanical cues and sustained growth factor delivery. The objective of this study is to engineer a mechanically tuned, bioactive hybrid scaffold system that integrates tendon-derived stem cells (TDSCs) and mesenchymal stem cells (MSCs), controlled growth factor release, and progressive mechanical stimulation to achieve functional tendon regeneration with enhanced structural and mechanical recovery. Scaffolds were fabricated with controlled pore architecture and fiber alignment. TDSCs were seeded dynamically and cultured under cyclic uniaxial strain (5%, 1 Hz, 4 h/day) with TGF-β3-loaded PLGA microspheres (release >21 days). In vitro assays assessed viability, proliferation, scleraxis/tenomodulin expression, collagen I/III ratio, and GAG content. In vivo evaluation used a rat Achilles tendon defect model (6 mm gap) with four groups: scaffold-only, scaffold+TDSCs, scaffold+TDSCs + TGF-β3, and scaffold+TDSCs + TGF-β3 + mechanical preconditioning (the full composite). Outcomes at 6 and 12 weeks included biomechanical testing, histology (collagen alignment, vascularity), and immunohistochemistry. The full composite group achieved 92% cell viability at 14 days, 8-fold upregulation of scleraxis, and organized collagen I deposition (60 ± 6 µg/mg). Cyclic strain improved collagen alignment by 3.5-fold versus static controls. In vivo, the full composite restored 88% of native tendon tensile strength by week 6 and 95% by week 12, with minimal adhesion formation and near-native ECM organization. The preconditioned groups showed significantly lower inflammatory scores and higher tenomodulin expression. Mechano-activated, growth factor-eluting scaffolds with TDSCs achieve superior tendon regeneration by combining biochemical and biophysical cues. This strategy offers a scalable, off-the-shelf, or autologous solution for clinical tendon repair.
Biomechanics and modeling in mechanobiologyJason K D Chan, Eric A Chadwick, Daisuke Taniguchi, Mohammadali Ahmadipour, Takaya Suzuki, David Romero, Cristina Amon, Thomas K Waddell, Golnaz Karoubi, Aimy …
We created computational fluid dynamic models of murine lung vasculature to assess the quantity and quality of cell deposition for lung re-endothelialization under three cell seeding protocols. These protocols include the standard direct injection seeding, negative pressure seeding, and a novel dual boundary condition seeding protocol. Our results indicate that cell seeding efficiencies are similar between the direct injection and negative pressure seeding protocols. The dual boundary condition protocol, which utilizes the direct injection of cell media with the addition of a prescribed pressure boundary condition at the parenchyma, exhibited increased cell deposition efficiencies of up to 14% compared to the direct injection and negative pressure cases, as well as the ability to target cell deposition in specific (i.e., proximal and distal) regions of the lung vasculature. This novel dual boundary condition protocol has the potential to increase cell seeding efficiencies during scaffold recellularization, addressing a significant challenge in the field of lung bioengineering.
BMC medicineXinyu Fu, Li Yan, Zhaosen Chen, Bohan Dou, Dezhi Zhou, Xinyao Zhou, Kengyuan Qu, Che Gao, Peiliang Wang, Fengzhi Zhang, Zihao Zou, Taoxia Wang, Guiying Li, Lil…
BACKGROUND: Ischemic vascular diseases remain a major clinical challenge, creating a need for engineered vascular tissues that can establish functional vascular networks and promote durable tissue repair. Conventional vascular organoids offer limited control over cellular composition and spatial organization, while the fate and adaptive remodeling of graft-derived human vascular cells after transplantation remain poorly understood. METHODS: Human vascular organoid sheets (hVOS) were constructed by extrusion-based three-dimensional (3D) bioprinting of human pluripotent stem cell (hPSC)-derived endothelial cells (ECs) and smooth muscle cells (SMCs) at a defined ratio within a gelatin methacryloyl (GelMA)-based bioink under chemically defined conditions. Vascular organization and cellular states were characterized using functional assays, immunofluorescence imaging, and single-cell RNA sequencing (scRNA-seq). Therapeutic efficacy and graft remodeling were evaluated in a murine hindlimb ischemia model using laser speckle perfusion imaging, histological analysis, intravital two-photon imaging, and scRNA-seq of recovered graft-derived human cells. RESULTS: Co-bioprinting ECs and SMCs accelerated vascular network formation and generated stable, interconnected vascular structures that underwent progressive maturation during culture. scRNA-seq identified diverse vascular and stromal populations and revealed transcriptional programs associated with vascular maturation, mechanotransduction, and hypoxic adaptation. Following transplantation, hVOS significantly improved blood perfusion, increased limb salvage, and promoted ischemic tissue repair. Intravital imaging detected circulating dextran within GFP-labeled hVOS-derived vascular structures at days 14 and 28, demonstrating perfusion of graft-derived vascular structures by the host circulation. Post-transplantation scRNA-seq revealed substantial adaptive remodeling of graft-derived ECs toward venous-biased and inflammatory states, accompanied by activation of NF-κB- and stress-associated programs. Transplanted SMCs and fibroblasts also exhibited coordinated transcriptional changes associated with wound healing and extracellular matrix remodeling. CONCLUSIONS: hVOS provide a reproducible and design-flexible 3D-bioprinted vascular tissue platform that enables controlled multicellular organization and formation of prevascularized constructs while supporting vascular integration and ischemic tissue repair in vivo. Single-cell analyses further reveal substantial adaptive remodeling of graft-derived vascular and stromal cells following transplantation. These findings support hVOS as a versatile platform for vascular regenerative medicine and for investigating the in vivo behavior of engineered human vascular tissues. Graphical abstract illustrating the generation and therapeutic application of human vascular organoid sheets (hVOS). hPSC-derived endothelial cells (hPSC-ECs) and smooth muscle cells (hPSC-SMCs) are precisely organized by 3D bioprinting to generate reproducible hVOS with enhanced vascular maturation driven by cellular, hypoxic, and biomechanical cues. Following transplantation into ischemic tissue, hVOS integrate with the host vasculature and undergo dynamic endothelial remodeling, enhancing perfusion and promoting tissue repair.
The Chinese journal of dental researchBoon Chin Heng, Yang Liu, Yun Yang Bai, Xiao Na Zheng, Jia Song, Qun Cui, Wan Li Song, Xue Hui Zhang, Xu Liang Deng
The increasing global incidence of bone injuries and degenerative diseases, often compounded by conditions like diabetes and osteoporosis, presents a significant health care challenge. Critical-sized bone defects frequently fail to heal due to compromised bioelectric microenvironments. This review summarises the conceptual framework of electric microenvironment remodelling in bone tissue, covering its physiological basis, disruption in disease and therapeutic modulation using electroactive scaffolds. The authors outline how the electric microenvironment of bone tissue is generated and continuously remodelled physiologically, analyse how its deficiency compromises regeneration and highlight strategies for dynamic regulation under pathological conditions. Restoring the bioelectric environment via electroactive scaffolds promotes bone healing by enhancing osteogenesis, angiogenesis and immunomodulation, while suppressing bone resorption. Diverse electroactive materials, including piezoelectric polymers and self-powered nanogenerators, are critically examined. Future bone tissue engineering will likely involve smart composite electroactive scaffolds that respond to external stimuli, enabling non-invasive, dynamic and precise modulation of electrical signalling cues for effective treatment of complex bone defects.
The pronounced heterogeneity of the pathological microenvironment in musculoskeletal disorders poses significant challenges to the spatiotemporal regulation capabilities of conventional therapeutic strategies. Stimuli-responsive hydrogels have exhibited immense potential for the treatment of musculoskeletal disorders owing to their excellent intelligent response characteristics and versatile design. This review systematically summarizes the major response mechanisms of stimuli-responsive hydrogels and analyzes the characteristics of their structural and functional design. It further focuses on recent advances of their applications in typical musculoskeletal disorders, including degenerative diseases such as osteoarthritis (OA); autoimmune diseases such as rheumatoid arthritis (RA); traumatic injuries such as fractures and cartilage injury; infectious diseases such as infected bone defects; metabolism-related bone disorders such as diabetic bone injury and hyperlipidemia bone injury; as well as soft tissue complications such as tendon adhesion and rotator cuff injury. Finally, this review proposes a design concept for multimodal stimuli-responsive hydrogels and discusses the key challenges in their clinical translation. We hope this review will serve as a reference for promoting the treatment of musculoskeletal disorders from passive repair to active regulation.
Biotechnology lettersMingyang Lv, Qi Wu, Yi Xu, Fei Guan, Xianggui Kong, Wenying Shi
By 2050, surging global population will intensify food insecurity, making it imperative to develop innovative strategies that boost plant productivity. Plants are our core food supply. Engineered nanoparticles have emerged as promising growth stimulants; however, carbon nanotubes (CNTs), despite their efficacy, are inedible and pose eco-toxicity concerns that restrict their agrobiological deployment. Furthermore, conventional whole-tissue studies obscure individual cell responses, preventing precise characterization of nanoparticle-cell interactions. Here, we introduce magnesium-aluminium layered double hydroxide (MgAl-LDH) nanoparticles, which is a food-grade material derived from commercial antacid formulations, that outperformed CNTs in accelerating plant cell development. This enhancement is suggested to be associated with the presence of magnesium ions and the positively charged LDH surface architecture, although the detailed molecular mechanisms remain to be fully elucidated.
Journal of applied oral science : revista FOBStephanie Isabel Diaz Zamalloa, Caroline Carvalho Dos Santos, Leticia Martins Santos, Victor Elias Arana-Chavez, Fernando Neves Nogueira, Carla Renata Sipert, …
INTRODUCTION: The unpredictability of blood clots as natural scaffolds in regenerative endodontic procedures (REPs) has driven the search for synthetic alternatives with reproducible properties. This study aimed to develop and characterize a dual-scale micro/nanofibrous poly(lactic-co-glycolic acid) (PLGA) scaffold fabricated by co-electrospinning and evaluate its physicochemical and biological suitability for REPs under lipopolysaccharide (LPS)-induced inflammatory conditions. METHODOLOGY: A 7.5% (w/v) PLGA solution was co-electrospun using distinct parameters (flow rate and needle-to-collector distance) to generate a dual-scale fiber architecture. Physicochemical characterization included water uptake, in vitro degradation, and morphological analysis by scanning electron microscopy (SEM). Biological properties were evaluated using human apical papilla cells (APCs). Metabolic activity (Alamar Blue), mineralization (Alizarin Red S), and cell adhesion/morphology (SEM) were assessed in the presence or absence of LPS to simulate an inflammatory environment. RESULTS: The co-electrospun scaffold showed a hierarchical structure with interconnected micro and nanofibers. Water uptake reached 147.4% within 24 h and increased gradually thereafter. The scaffold showed a biphasic degradation profile-slow initial degradation (21.5% over 28 days) followed by accelerated loss (63.1% at day 45). Hydration induced fiber swelling and pore remodeling. The scaffold supported APC adhesion, spreading, and metabolic activity over 72 h. Under LPS stimulation, APCs maintained metabolic activity and showed robust mineralization potential after 21 days, comparable to the positive control. CONCLUSION: The co-electrospun PLGA scaffold showed physicochemical properties compatible with tissue ingrowth and supported APCs function under inflammatory conditions. By providing a controlled microenvironment, it represents a potential scaffold design for future REPs.
Cell-laden three-dimensional (3D) bioprinted hydrogels have emerged as a promising technique for enhanced wound healing by integrating biomaterials, living cells, and precise fabrication technology. Chronic wounds that persist for an extended period of time, especially when pathologically affected by diseases like diabetes, can pose a serious threat to patients' health. Conventional dressing materials typically fail to provide adequate mechanical strength, drug release control, and complete tissue regeneration. In contrast, 3D bioprinting can allow for the selective deposition of cells into the extracellular matrix-mimetic hydrogels, making it possible to construct biomimetic scaffolds for tissue regeneration. This review provides a clear overview of how key cellular components such as mesenchymal stem cells, adipose-derived stem cells (ADSCs), fibroblasts, and multicellular systems contribute to important wound healing processes like immunomodulation, angiogenesis, cell proliferation, and re-epithelialisation. It also explores how bioprinting factors, including bioink rheology, cross-linking methods, and processing conditions, influence printability, the structural stability of scaffolds, and cell survival. The close relationship between scaffold design and how cells respond is emphasised as a key factor in determining how effective the treatment will be. Although pre-clinical studies have shown promising results, bringing this research into real-world clinical use remains challenging due to issues like lack of standardisation, difficulties in scaling up, regulatory hurdles, and high costs.
Zhonghua shao shang yu chuang mian xiu fu za zhiR X Wu, J M Shen, F Y Duan, B Chen, Q H Sheng, L Z Yang, X K Li, Q Xu, Z G Wang
Chronic wounds are characterised by factors including persistent inflammation, impaired angiogenesis, cellular dysfunction, and infection, which hinder the normal healing process, thereby not only severely compromising patients' quality of life but also imposing a substantial socioeconomic burden. For this type of wounds, conventional treatments are often limited in efficacy and associated with issues such as prolonged treatment duration and high costs. Recently, research on stem cells and their derivatives in the field of wound repair has been developing rapidly. Stem cells accelerate wound healing primarily through potent paracrine effects and immunomodulatory functions, complemented by multilineage differentiation potential, which synergistically modulate inflammation, promote angiogenesis, and facilitate collagen remodeling. Furthermore, engineering strategies including genetic modification, three-dimensional culture, and biomaterial-based delivery have significantly improved stem cell bioactivity and adaptability to the wound microenvironment. Concurrently, stem cell derivatives, particularly exosomes, have attracted increasing attention as a next-generation "cell-free" therapeutic strategy owing to their low immunogenicity, high stability, abundance of bioactive factors, and capacity for bioengineering modification. It offers a new approach to the precise regeneration of complex wounds. This review aims to review the pathological mechanisms underlying chronic wounds, research progress on therapeutic application of stem cells and their derivatives, engineering strategies, and translational challenges in clinical application, providing a reference for future research in the field.
Biomaterials advancesPeter Trosan, Franziska Frost, Jessica Hoerner, Jana Schaetzel, Thomas Eickner, Marcus Himmler, Susanne Staehlke, Volkmar Senz, Andreas Götz, Niels Grabow, Sab…
Descemet's Membrane Endothelial Keratoplasty (DMEK) is one of the most common therapies to re-establish visual acuity caused by corneal endothelial cell loss. Donor tissue shortages become increasingly relevant. Therefore, the main objective of this study was the evaluation of potential fiber substitute materials suitable for DMEK. Six electrospun biomaterials (three degradable: poly-l-lactide (PLLA), PLLA plus lecithin and tetraethylammonium chloride (PLLA+), polydioxanone (PDO); three non-degradable: polyurethanes (TSPEU, TSPCU), thermoplastic elastomer (TPC-ET) were examined regarding their structure, transparency, cell viability, metabolic cell activity, and endothelial phenotypic markers. Cell behavior was assessed on plasma-activated as well as on non-activated biomaterials to distinguish a possible influence of cold plasma activation. All biomaterials were suitable scaffolds for endothelial cells (HCEC) in varying degrees. No significant differences could be found between plasma-activated and non-activated scaffolds. PLLA+ ranked highest in total cell number. All biomaterials were comparable regarding cell toxicity, with high levels of cell viability. qPCR analysis revealed higher expression of genes responsible for HCEC's proliferation and morphology cultured on TSPEU, PLLA, and PLLA+. In summary, PLLA and PLLA+ showed the highest number of cells with high viability and cell proliferation whilst preserving their phenotype. In addition, PLLA and PLLA+ ranked highest in light transmission, which makes them promising candidates as artificial DMEK replacements.
Bioprinting has been proposed for nearly every structure of the anterior eye, but the effort is unevenly spent. We systematically reviewed 71 experimental studies of bioprinting across the anterior segment: cornea, conjunctiva, sclera, lens, lacrimal gland and eyelid. Most work targets the corneal stroma. The endothelium, the layer most often replaced surgically and the first to reach a clinical trial, accounts for the fewest preclinical studies. Beyond the cornea, printed constructs are mostly disease models rather than implants, and the iris, trabecular meshwork and ciliary body remain untouched. Preclinical testing remains short-term and confined to small animals. Studies measure the same properties in different ways, so constructs cannot be compared across laboratories. We map what has been printed for each tissue and how far each construct stands from the clinic, and propose a minimum reporting set to make the next generation of studies comparable.
Biomaterials advancesAnita Puspitasari, Thi Kim Ngan Duong, Anky Fitrian Wibowo, Vu Hoang Minh Doan, Truong Tien Vo, Jaeyeop Choi, Yong Hyun Kim, Jae Sung Ahn, Sudip Mondal, Junghw…
Artificial intelligence (AI), especially machine learning (ML) and deep learning (DL), is rapidly changing biomaterials science. These computational tools enable researchers to analyze large and complex datasets, discover new materials, and improve the design and performance of existing ones. ML and DL algorithms learn from experimental and simulation data to predict material properties, guide synthesis, and optimize manufacturing conditions, often faster than conventional trial-and-error approaches. In recent years, AI-based methods have been applied across biomaterials research, including predicting the biocompatibility and mechanical strength of new materials, improving additive manufacturing (AM) processes, and enhancing the precision of biofabrication and tissue engineering. AI tools are increasingly applied to real-time quality assessment and adaptive control during material production, enabling the design of "smart" biomaterials that respond dynamically to environmental and biological signals, with potential uses in regenerative medicine, healthcare devices, and sustainable materials. This emerging field still faces key challenges, such as the difficulty of obtaining large and reliable datasets needed to train accurate AI models. Another critical issue is the interpretability of complex ML and DL models. Understanding why an algorithm makes a certain prediction is essential for building trust and guiding experimental validation. To address these issues, researchers are turning to explainable AI (XAI) approaches that provide greater transparency and insight into model behavior. This review summarizes recent progress in applying ML, DL, and XAI to biomaterials science. It also highlights the main opportunities and challenges for developing intelligent, real-time adaptive materials for healthcare, regenerative medicine, and sustainable material design.
Cryogels have emerged as promising biomimetic scaffolds for extracellular matrix emulation in bone tissue engineering (BTE). In this study, we investigated how hydroxyapatite (HA) incorporation influences the physicochemical, mechanical, and biological performance of cryogels based on methacryloyl derivatives of type A gelatin, type B gelatin, and chondroitin sulfate (GelMAA, GelMAB, and CSMA, respectively). HA-enriched cryogels were fabricated through a one-pot cryogelation process in which HA particles were dispersed within the polymer solutions prior to crosslinking, without the use of additional dispersing agents. Scaffolds incorporating either commercial spheroidal HA or ultrasound-synthesized needle-to-plate HA were compared with non-mineralized counterparts as well as with each other, to evaluate the effect of the mineral phase on the resulting cryogels properties. The different polymer matrices exhibited distinct capacities to stabilize and homogeneously incorporate HA. Negatively charged polymers (GelMAB and CSMA) enabled HA incorporation up to 10% w/w, whereas GelMAA efficiently incorporated only 2.5% w/w. However, increasing mineral content did not result in improved mechanical properties or biological performance, suggesting that alterations in cryogel pore architecture and interconnectivity outweighed the benefits of higher mineral loading. Biological evaluation revealed limited cell response in CSMA-based cryogels, while GelMA-based systems supported cell adhesion and viability, with GelMAA yielding marginally more favorable outcomes. Furthermore, HA crystal morphology had only a minor influence on scaffold performance, including osteoinductive potential. Overall, the results indicate that the composition of the polymer matrix plays a more critical role than HA loading or crystal morphology in determining the functional performance of mineralized cryogels for BTE.
Liver fibrosis is a hallmark pathological feature of chronic liver diseases and poses a major threat to the health of millions of people worldwide. Without timely diagnosis and effective intervention, liver fibrosis can progress to cirrhosis, liver failure, and even hepatocellular carcinoma (HCC). The limited availability of donor organs for orthotopic liver transplantation has driven the continuous search for alternative therapeutic strategies. However, conventional approaches, including pharmacotherapy, RNA-based therapies, and cell therapy, are often limited by insufficient therapeutic efficacy, poor targeting, and significant adverse effects, underscoring the urgent need for more effective treatment strategies. In recent years, biomaterials have emerged as promising platforms for liver fibrosis therapy owing to their excellent biocompatibility and tunable physicochemical properties. This review summarizes the recent advances in biomaterial-based therapeutic strategies for liver fibrosis, with a particular focus on nanomaterials, hydrogels, and microsphere-based delivery systems. The advantages and limitations of these biomaterial platforms are systematically discussed. Furthermore, we highlight the dual role of biomaterials not only as delivery vehicles for antifibrotic drugs, nucleic acids, and therapeutic cells but also as active platforms that modulate the fibrotic microenvironment and promote liver regeneration. Finally, the current status and future perspectives of biomaterial-based approaches in liver tissue engineering are discussed.
Despite major advances in liver-on-a-chip and organoid technologies, most current in vitro liver models remain limited. Here, it is argued that these limitations are fundamentally conceptual rather than purely technical. Reverse bioengineering is introduced as a unifying design framework for liver-on-a-chip systems, in which human liver development is treated as the primary engineering blueprint rather than adult hepatic phenotype as the endpoint. Existing cell sources, liver organoids, and liver-on-a-chip platforms are critically evaluated, demonstrating that each capture complementary but incomplete aspects of liver development. Pluripotent stem cells uniquely enable access to intrinsic developmental programs and cellular diversity, organoids partially reconstruct early developmental trajectories through self-organization, and microphysiological systems provide extrinsic cues without fully encoding developmental execution. Finally, futured directions are outlined, highlighting developmentally coordinated multi-organ systems, quantitative developmental benchmarks, and the emerging role of multi-omics-enabled Digital Twins and artificial intelligence in guiding and interpreting liver-on-a-chip design.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgeryKun Yang, Yuanlin Sun, Rui Bai, Yunkang Yang
OBJECTIVE: To review the research progress on the major microenvironmental abnormalities in diabetic bone defect repair and functional biomaterial-based intervention strategies. METHODS: Relevant literature on diabetic bone defect repair and functional biomaterial-based interventions was reviewed and synthesized, with emphasis on the core pathological features of the diabetic bone defect repair microenvironment, principal regulatory strategies, representative material platforms, and the current status of clinical translation. RESULTS: Persistent hyperglycemia promotes the accumulation of advanced glycation end products and excessive generation of reactive oxygen species (ROS), together with osteoimmune dysregulation, unresolved chronic inflammation, and microvascular dysfunction. These abnormalities collectively impair cell recruitment, vascular regeneration, and new bone formation. Functional biomaterials are designed to modulate macrophage polarization and inflammatory responses, restore angiogenic-osteogenic coupling, and enable on-demand therapeutic release in response to pathological cues such as glucose and ROS, thereby improving the local regenerative microenvironment. Hydrogels, bioactive inorganic or composite materials, and multifunctional delivery systems constitute the principal material platforms. However, their broader application remains limited by inadequate mechanical suitability, insufficient manufacturing reproducibility, and a lack of robust clinical evidence. CONCLUSION: Sustained dysregulation of the local microenvironment is a central determinant of impaired diabetic bone defect repair. Future biomaterial design should prioritize the precise recognition and active remodeling of the diabetes-specific pathological microenvironment to enhance bone regeneration and osseointegration.
Hydrogels are distinguished by their high-water content, superior biocompatibility, and stimuli-responsive properties, which have found widespread applications in biomedical domains such as drug delivery, tissue engineering, and wound healing. However, conventional hydrogels are often hindered by intrinsic drawbacks such as inferior mechanical strength, unstable cross-linking, and a lack of antibacterial activity, which restrict their practical applications. To enhance the comprehensive performance of hydrogels, modification via chemical or physical strategies has been employed to optimize both the functional characteristics and mechanical properties. Among various modifying agents, siloxane-based materials have garnered increasing attention as novel modifiers due to their versatile functional groups as well as chemical and physical properties. The interactions between siloxanes and hydrogels facilitate the formation of robust polymer network structures, achieving a synergistic enhancement in physicochemical properties and functionality. Given the extensive variety of siloxane-based materials, this review follows the classification of D-, T-, and Q-type siloxanes and summarizes their distinct modification strategies for hydrogels. The reinforced effects, intermolecular interactions and biomedical applications of siloxane-hydrogel composites are mainly discussed. This review provides an outlook on the future development of advanced siloxane-hydrogel hybrids through the rational design of hydrogels with siloxanes.
BiomacromoleculesAna Quintana-Prego, Atocha Guedan-Duran, Gustavo Victor Guinea, Juan Gomez-Rivas, Fivos Panetsos
Tissue engineering seeks effective strategies to integrate cells into scaffolds while preserving spatial organization and stability. Conventional approaches based on extracellular matrix molecules or adhesion peptides often provide weak and nonspecific attachments, limiting robust assembly of complex cellular architectures. Here, we investigate biorthogonal click chemistry to address these limitations. By enabling covalent cell-biomaterial bonding through strain-promoted azide-alkyne cycloaddition (SPAAC), we achieved stable cell-scaffold integration. As a proof of concept, we engineered artificial Bands of Büngner-like scaffolds by functionalizing silk microfibers with cyclooctyne groups and metabolically engineering Schwann cells to present azide functionalities. Over 15 days in vitro, these biohybrid scaffolds supported directed neurite outgrowth, preserved metabolic activity, and increased nerve growth factor levels at early time points. Our results support click chemistry as a robust strategy for assembling stable cell-laden scaffolds while preserving biological function, potentially enabling the tailored design of complex cellular architectures and microenvironments for tissue engineering applications.
Chembiochem : a European journal of chemical biologyHao Xia, Xiaoya Wang, Wei Chen
The inadequate nerve networks in regenerated bladders remain a significant challenge in bladder tissue engineering. Our previous studies have demonstrated that incorporating basic fibroblast growth factor (bFGF) and urine-derived stem cells (USCs) into bladder acellular matrix (BAM) enhances bladder repair. While these approaches have shown promising results in regenerating bladder epithelium and smooth muscle, the outcomes of neural regeneration are still not satisfactory. Therefore, this study introduces the 1-14aa sequence from the NGF polypeptide (NMP), a small molecule NGF peptidomimetic, which could improve neural regeneration in the body. Utilizing the tissue inhibitors of metalloproteinases (TIMP) that is cleaved by MMP-2 to design an MMP-2 responsive NMP delivery system, which could control the release of NMP according to the amount of MMP-2 in the local microenvironment. By chemical cross-linking, NMP-TIMP and bFGF were conjugated with BAM seeded with USCs to compose BAM/USCs/bFGF/NMP-TIMP functional biomaterial. Using a rat bladder reconstruction model, the functional biomaterial significantly enhanced the regeneration of endothelial cells, capillaries, smooth muscle cells, nerve fibers, and the bladder functions. In summary, the BAM/USCs/bFGF/NMP-TIMP functional biomaterial may offer a promising strategy for tissue-engineered bladder by promoting bladder regeneration, especially the regeneration of bladder nerves.
PURPOSE: Biotube/Biosheet, collagenous tissue membranes generated by in-body tissue architecture, have been used as scaffolds in various tissue engineering applications. However, their use in vaginal reconstruction has not been reported. This study aimed to evaluate the biocompatibility and potential utility of Biotube/Biosheet as scaffolds for vaginal reconstruction in a rat model. METHODS: A cylindrical mold was implanted subcutaneously on the backs of rats to generate Biotube/Biosheet. Two models were established: a partial defect of the posterior vaginal wall and a complete circumferential implantation. In each model, trimmed Biotube/Biosheet was sutured into place. Rats were euthanized 4 to 14 days after surgery for macroscopic and histological evaluation. RESULTS: An epithelial extension from the residual vagina along the luminal surface of the Biotube/Biosheet was observed and eventually reached the vaginal orifice, resulting in complete mucosal coverage. The Biotube/Biosheet was gradually infiltrated and replaced by granulation tissue, and muscular tissue extended toward the vaginal orifice. No neutrophil or lymphocyte infiltration suggestive of acute rejection was detected. CONCLUSION: Biotube/Biosheet shows promise as a scaffold for vaginal reconstruction. Long-term follow-up studies are needed to determine whether it is fully replaced by normal vaginal tissue and whether the reconstructed vagina can support pregnancy and childbirth.
Cell sheet engineering (CSE), a scaffold- and biomaterial-free biofabrication technique, preserving native extracellular matrix and cell-cell junctions, is re-emerging as a powerful therapeutic modality. With over 70 registered clinical trials worldwide, the technology has demonstrated clinical validity by providing preserved tissue architecture. Recent evolutions such as those in anchored cell sheet engineering, mark an inflection point, enabling formation of more relevant form factors with higher levels of phenotypical and microstructural maturity with improved structural and functional competence, expanding CSE's addressable scope. Regulatory momentum is growing, with the gap between current cell-based release testing and tissue-level function emerging as the central regulatory challenge for living tissue products. Simultaneously, automation is transforming CSE's cost structure, with closed-loop systems potentially reducing manufacturing costs by ∼30% from current facility- and personnel-dominated models. Commercial precedents demonstrate that biologically complex constructs can achieve reimbursement and clinical integration when aligned with procedural workflows and measurable outcomes. This perspective examines how CSE represents a high-value platform for a strategically significant and expandable subset of regenerative medicine, positioned to serve a substantial market segment. Future advances could expand its applications to larger multi-tissues constructs, where recreating native tissue architecture provides decisive therapeutic advantage.
This study aimed to simplify the fabrication process of bone tissue engineering scaffolds by developing a composite scaffold based on chitosan (CS), sodium alginate (SA), pectin (PEC), and 45S5 bioactive glass (BG) through an integrated one-step CaCl2-mediated crosslinking method. Scaffolds were prepared with varying BG mass fractions (10, 20, 30, and 40 wt%, named CSAP@BG10, CSAP@BG20, CSAP@BG30, and CSAP@BG40) by mixing CS, SA, and PEC solutions (dry ratio 50:40:10) with BG particles. The resulting mixture was then subjected to shaping, Ca2+-mediated crosslinking, freezing, and freeze-drying. Characterization included porosity assessment, infrared spectroscopy (IR), x-ray diffraction (XRD), and simulated body fluid (SBF) evaluation.In vitrostudies were performed using bone marrow-derived mesenchymal stem cells (BMSCs). The CSAP@BG20 scaffold exhibited an interconnected porous structure, a favorable swelling ratio, and notable mass retention after degradation. IR and XRD analyses confirmed the successful incorporation of the BG and the retention of its amorphous structural characteristics within the scaffold. A bone-like apatite layer formed on the scaffold after SBF immersion, indicating favorablein vitrobioactivity. In addition, immersion studies showed composition-dependent physicochemical behavior, including mild pH variation and sustained Ca2+release. BMSCs exhibited enhanced adhesion, proliferation, and osteogenic gene expression in CSAP@BG20 compared with the BG-free control. It also upregulates angiogenic-related factors, demonstrating synergistic osteogenic and angiogenic effects. The integrated one-step CaCl2-mediated fabrication strategy successfully created a scaffold with favorable structure, mechanical properties, and bioactivity. Among the tested formulations, CSAP@BG20 showed the most balanced physicochemical and biological performance. The CSAP@BG20 scaffold shows promise for bone defect repair.
ACS applied bio materialsJun Zhuang, Jiangyi Wu, Yuan Ma, Lin Yin, Yongqian Wang
The repair of craniofacial bone defects remains a significant challenge in regenerative medicine due to their unique embryonic origin (cranial neural crest cell-derived) and complex anatomical functions. To address the scarcity of autologous bone sources and the tumorigenic risks associated with traditional stem cell therapies, stem cell-derived extracellular vesicles (SC-EVs) offer a highly promising cell-free therapeutic strategy. However, a systematic summary of how to develop efficient EV-based treatments tailored to the specific osteogenic microenvironment of the craniofacial region is still lacking. This review systematically summarizes the current applications of SC-EVs in craniofacial bone tissue engineering. The article first focuses on mechanistic analysis, elucidating how EVs promote the repair of calvarial, alveolar, and jaw bones by delivering bioactive molecules (such as miRNAs and proteins) to activate osteogenic/angiogenic signaling pathways and modulate the inflammatory microenvironment. Finally, this paper reviews engineering modification strategies for SC-EVs, including donor cell pretreatment (hypoxia and inflammatory cytokine stimulation) and SC-EV drug loading/surface modification techniques, and explores the challenges and future prospects of SC-EVs in clinical applications.