The intestinal mucus layer forms the interface between the gut microbiota and the epithelium, and in vitro platforms are needed to study host-microbe interactions at this interface. However, such platforms must reconcile conflicting conditions: obligately anaerobic bacteria require a low-oxygen environment, whereas epithelial cells require conditions compatible with barrier maintenance. In addition, simple co-culture systems lack a glycan-presenting mucus matrix. Here, we established a co-culture platform in a conventional Transwell format without complex microfluidic devices by integrating a mucin matrix with a simple oil-based method for restricting oxygen influx. Using polyethylene oxide (PEO) as a transient spinning aid and removing it after glutaraldehyde crosslinking, we fabricated a three-dimensional porous hydrogel fiber composed predominantly of porcine gastric mucin (PGM). The fiber retained the examined mucin-derived O-linked glycan epitope on its surface. Bifidobacterium bifidum adhered to and proliferated on the fiber, forming a biofilm-like structure and infiltrating the porous network. In nutrient-restricted medium, bacterial growth occurred only in the presence of the fiber; this result demonstrates growth associated with the presence of the fiber but not O-glycan-specific utilization. A mineral oil overlay restricted oxygen influx and, together with oxygen consumption by Caco-2 cells, lowered the dissolved O2 concentration at the sensor position immediately beneath the epithelial layer to approximately 0.1 mL/L (approximately 2% of air saturation). Combining methylcellulose, the mucin hydrogel fiber, and mineral oil enabled co-culture while maintaining both epithelial barrier function, as assessed by transepithelial electrical resistance (TEER) and zonula occludens-1 (ZO-1) staining, and B. bifidum viability, as assessed by reculture. This mucin-predominant, glycan-presenting hydrogel fiber provides an accessible, device-free platform for studying the intestinal host-microbe interface.
Alzheimer's disease (AD) is characterized, among other factors, by the accumulation of the β-amyloid peptide (Aβ), redox imbalance, and disruption of metal homeostasis-processes that act synergistically, promoting neurotoxicity. In this work, a core-shell nanosystem based on mesoporous silica-coated gold nanorods (GNR@mSiO2) was developed, functionalized with the anti-Aβ aggregation D3 peptide and loaded with epigallocatechin-3-gallate (EGCG), an antioxidant and modulator of Aβ aggregation and toxicity, to reduce Aβ-induced toxicity in vitro in presence of Zn(II) ions. Nanosystem formation and the incorporation of each component were confirmed by transmission electron microscopy (TEM), UV-Vis-NIR spectroscopy, dynamic light scattering (DLS), ζ-potential, and fourier transform infrared (FT-IR) spectroscopy. The GNR@mSiO2-PEG-D3/EGCG nanosystem exhibited high antioxidant activity, evidenced by its ability to sequester metal ions and deactivate DPPH• and •OH radicals. Furthermore, it effectively inhibited Aβ aggregation and promoted its disaggregation, particularly under Zn(II) ions overload conditions. In differentiated SH-SY5Y neuronal cells, the nanosystem converted Aβ aggregates formed in the presence of Zn(II) ions into non-toxic species, resulting in a marked reduction of cytotoxicity and intracellular ROS production. Taken together, these findings highlight the potential of GNR@mSiO2-PEG-D3/EGCG as a promising multifunctional platform against AD.
The convergence of microfluidic engineering and organ-on-a-chip (OoC) technology is redefining the development and preclinical validation of polymer-based drug delivery systems and biomedical preparations. This review presents a bidirectional framework: first, how microfluidics enables precision synthesis of polymer particles with controlled size, morphology and multifunctionality; second, how OoC platforms serve as physiologically relevant testbeds to evaluate these particles under dynamic, human-mimetic conditions. We examine droplet microfluidics principles for generating monodisperse polymer particles (spheres, Janus, core-shell, porous architectures) from natural and synthetic polymers. These particles are explored as functional additives within OoC systems, as embedded sensors for real-time oxygen/pH monitoring, as controlled-release depots for localized growth factor delivery and as building blocks (microscaffolds, bioinks, spheroid templates) for constructing three-dimensional tissue microenvironments. Conversely, we critically analyze how OoC platforms, including vascularized tumor models, liver-kidney multi-organ chips and blood-brain barrier systems, enable more physiologically relevant assessment of micro- and nanoparticle transport, extravasation, toxicity, immunogenicity and metabolism under fluidic shear and multi-cellular complexity, which are capabilities inaccessible to static cultures. Current challenges (scalability, GMP compliance, standardization, regulatory context-of-use) and emerging opportunities (smart responsive particles, personalized screening using patient-derived organoids, AI-driven automation and closed-loop optimization) are critically discussed. This review demonstrates that microfluidic particle engineering and OoC technology together form an iterative framework for advancing next-generation biomaterials and supporting their preclinical-to-clinical development pathway.
Radiation-induced skin injury (RISI) is one of the major complications of tumor radiotherapy, and remains clinically unaddressed due to insufficient wound healing and high infection risks. To address this clinical challenge, this study developed a novel multifunctional composite material based on a DNA hydrogel. This material innovatively integrates polydopamine-modified graphene oxide (PDA@GO) and fibroblast growth factor 2 (FGF2) into a DNA hydrogel matrix, achieving integrated therapeutic effects in radioprotection and tissue repair. Specifically, PDA@GO, with its excellent free radical scavenging ability, effectively eliminates excessive reactive oxygen species (ROS) in the wound microenvironment. Meanwhile, the unique three-dimensional porous network structure of the DNA hydrogel acts as an ideal sustained-release carrier for FGF2, significantly enhancing its bioavailability. Both in vitro and in vivo experiments demonstrated that this composite material demonstrates excellent biocompatibility, anti-inflammatory properties, and radioprotective performance. Compared with similar radioprotective agents and conventional clinical treatments, the FGF2-PDA@GO/DG hydrogel showed significant advantages in promoting wound healing and alleviating radiation-caused damage. These results support an encouraging biomaterial-based strategy for treating radiation-induced skin injury.
Adipose-derived stem cells (ADSCs) are promising for cartilage regeneration, but efficient, safe strategies to enhance chondrogenesis remain limited. This study examined frequency-dependent effects of microcurrent stimulation (MS) on rabbit ADSCs cultured as monolayers and three-dimensional spheroids. Cells were exposed to 0 Hz, 10 Hz, 100 Hz, 1 kHz, 10 kHz, or 60 kHz MS for 20 min daily. Chondrogenesis, extracellular matrix deposition, spheroid morphology, mechanical properties, inflammatory/catabolic responses, apoptosis, and Ca2+-calcineurin-NFAT signaling were evaluated. Among tested frequencies, 1 kHz MS most effectively enhanced chondrogenic differentiation, increasing SOX9, COL2A1, ACAN, and COMP expression and promoting collagen II and glycosaminoglycan deposition. It also improved spheroid morphology and mechanical properties while suppressing fibrocartilaginous, hypertrophic, inflammatory, and catabolic markers. MS did not alter medium pH, temperature, or reactive oxygen species levels and did not impair viability or increase apoptosis. Mechanistically, 1 kHz MS promoted Ca2+ influx, NFAT nuclear translocation, and NFATc1 expression; inhibition of L-type Ca2+ channels, intracellular Ca2+, or calcineurin attenuated this response. These findings identify frequency-tuned MS as a noninvasive strategy for promoting ADSC chondrogenesis and cartilage-like matrix formation.
Biofilm-associated wound infections and antimicrobial resistance urgently require non-antibiotic therapies that integrate efficient antibacterial activity with tissue repair. Herein, we developed a sandwich-like trilayer Ag/CuO@PDA nanoplatform composed of one-dimensional CuO nanowires, Ag nanoparticles, and a polydopamine (PDA) photothermal shell. Under 980 nm near-infrared (NIR) irradiation, PDA-mediated local heating enhanced CuO-driven reactive oxygen species (ROS) generation and significantly promoted Ag+/Cu2+ release, as verified by ICP-MS analysis. Ag/CuO@PDA combined with NIR showed potent broad-spectrum antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA)and Escherichia coli (E. coli) and effectively disrupted mature biofilms by damaging bacterial membranes, increasing membrane permeability, and inducing intracellular component leakage. Meanwhile, the nanoplatform exhibited favorable cytocompatibility and supported wound-healing-related cellular behaviors, including cell migration and endothelial tube formation. In an Staphylococcus aureus (S. aureus) -infected wound model, Ag/CuO@PDA + NIR markedly reduced bacterial burden, alleviated inflammation, promoted collagen deposition and angiogenesis, and accelerated wound closure without obvious systemic toxicity. Overall, this trilayer nanoplatform integrates photothermal conversion, ROS generation, and metal ion-mediated antibacterial action, offering a promising non-antibiotic strategy for treating biofilm-associated infected wounds while promoting tissue repair.
The Arginine-Glutamic acid-Aspartic acid-Valine (Arg-Glu-Asp-Val, REDV) peptide selectively binds endothelial cells but exhibits limited multifunctional bioactivity for cardiovascular applications. Sulfonation has been reported to confer multi-cellular regulatory functions to various biomolecules. In this study, sulfonated REDV peptides (S-REDV) with sulfur contents of 3.56 ± 0.10, 4.20 ± 0.23, 5.39 ± 0.13, and 5.98 ± 0.08 at.% were prepared by controlling the reaction time. Comprehensive cytocompatibility evaluations revealed that a moderate sulfonation degree (S-REDV-3) significantly enhanced human umbilical vein endothelial cell (HUVEC) proliferation, nitric oxide (NO) release and migration. Moreover, it restrained excessive smooth muscle cell (SMC) proliferation, preserved the contractile phenotype of SMCs, and drove macrophage polarization toward an anti-inflammatory phenotype. In contrast, excessive sulfonation resulted in structural degradation and compromised bioactivity. These results indicate that appropriately sulfonated REDV, particularly S-REDV-3, may serve as a promising bioactive peptide for surface functionalization of cardiovascular biomaterials.
Current hemostatic materials often face challenges associated with delayed action and insufficient stability on wet bleeding surfaces. Here, we designed and screened three short self-assembling peptides by integrating amphiphilic motifs, β-sheet-associated assembly, and intrinsic antioxidant properties. Through systematic comparison of sequence variants, peptide P3 (PYFKWS) was identified as the optimized candidate, exhibiting enhanced hemostatic and wound-healing performance. Structural interrogation revealed that P3 adopts a β-sheet-stabilized amphiphilic architecture, enabling rapid in situ hydrogel formation within physiological milieu. Molecular simulations further indicated that the superior assembly behavior of P3 was associated with a more favorable intermolecular hydrogen-bonding organization rather than the total hydrogen-bond number alone. This rapid self-assembly facilitates hemostasis through hydrogel-mediated physical sealing, erythrocyte adsorption, and platelet recruitment. Augmenting this structural advantage, the indole moieties and phenolic hydroxyl constituents within P3 collectively confer notable radical-scavenging capacity, contributing to oxidative stress modulation. This effect significantly dampens pro-inflammatory responses (TNF-α: ↓63.2%; IL-6: ↓58.7% vs control) and promotes a microenvironment favorable for tissue repair. Validated in mouse tail bleeding, rat liver injury, and full-thickness wound models, P3 significantly reduced hemostasis time and blood loss while accelerating wound closure. This study demonstrates a minimal peptide design strategy that integrates rapid hemostasis with oxidative stress regulation and tissue repair, providing insights into the development of multifunctional peptide-based hemostatic materials.
The hierarchical structure of bone governs both mechanical behavior and mechanobiological signaling, yet most Bone Tissue Engineering (BTE) scaffolds reproduce only meso-scale porosity while neglecting the Lacuno-Canalicular Network (LCN), a key regulator of interstitial fluid flow. Here, we present a multi-scale bio-inspired scaffold integrating synchrotron μ-CT-derived trabecular architecture with a computationally engineered LCN-like micro-porosity. Two micro-network topologies, Regular and Canalicular-like, were fabricated via two-photon polymerization using IP-VISIO, here applied for the first time in a BTE context. Computational fluid dynamics revealed topology-dependent transport behavior: the Canalicular-like architecture exhibited >40% higher permeability and more homogeneous wall shear stress distributions within osteogenic-relevant ranges compared to the Regular design. Human bone marrow-derived mesenchymal stromal cells were cultured onto scaffolds under static conditions, showing cell attachment, osteogenic gene expression, and mineralized matrix deposition in both designs, assessed by SEM, RT-qPCR and Alizarin Red S staining. Synchrotron μ-CT showed mineral deposition throughout both trabecular regions and the engineered micro-network, with a more uniform spatial distribution in the Canalicular-like scaffold. Overall, this work proposes a multi-scale design framework and identifies LCN-inspired micro-architecture as a promising design variable for hierarchical bone scaffolds, influencing predicted fluid-dynamic behavior and supporting osteogenic culture.
Functionalization of cardiovascular implants is advancing to improve hemocompatibility, endothelialization, anti-inflammatory effects, and long-term patency. Conventional materials, including polymers, chemical grafts, and bioactive molecules, provide important biological benefits but do not fully replicate the complex biochemical and physiological cues of the native vascular microenvironment. Cell-derived materials, including decellularized extracellular matrix (dECM), cell membranes, extracellular vesicles (EVs), and secretomes, offer significant opportunities by preserving native structural proteins, adhesion molecules, lipid interfaces, and paracrine signaling factors. These biologically derived materials enhance endothelial repair, modulate inflammation, reduce neointimal hyperplasia, and promote vascular remodeling. Despite these advantages, substantial translational challenges remain, as many biofunctionalized implants exhibit inadequate coating adhesion, limited shear resistance, poor durability under pulsatile flow, and susceptibility to fatigue, delamination, or structural failure. This review summarizes recent advances in the functionalization and fabrication of cardiovascular implants using cell-derived materials, providing a systematic analysis of fabrication strategies, biological performance, mechanical properties, and device-specific challenges. Finally, we discuss common failure mechanisms, translational barriers, and future directions for developing scalable, mechanically robust, and clinically translatable cell-derived biomaterials for next-generation cardiovascular implants.
Extracellular matrix (ECM) hydrogels are essential for recapitulating native microenvironments in fundamental biomedical research, yet conventional animal tissue-derived products face challenges of cross-species variability or donor-related inconsistency. Human cell-derived matrix (hCDM) fabricated via cell sheet technology offers a promising alternative; however, its efficient fabrication remains constrained by the limited expansion capacity and inconsistent ECM deposition behavior of commonly used primary cells. To facilitate rational cell-source selection, we established a database-guided screening strategy integrating extracellular matrix-related expression profiles, proliferative characteristics, and commercial accessibility. Using primary human dermal fibroblasts (HDFs) as a functional reference, Hs 578 T cells emerged as a top-ranked candidate exhibiting strong ECM deposition potential together with robust proliferative capacity. In vitro validation confirmed that Hs 578 T cells exhibited ECM deposition capacity significantly exceeding that of HDFs. Under optimized serum-reduced conditions, Hs 578 T cells formed cohesive, protein-rich cell sheets that were successfully processed into structurally stable hCDM hydrogels retaining abundant collagens and other critical ECM components. Functional assessment demonstrated that the resulting hCDM hydrogel supports endothelial cell culture and three-dimensional vascular network formation at levels comparable to collagen type I hydrogel. These findings establish a database-guided workflow for rational seed cell selection, providing a strategy that bridges cell sheet cultivation with the efficient fabrication of human ECM biomaterials. STATEMENT OF SIGNIFICANCE: Developing human ECM biomaterials via cell sheet technology is frequently constrained by the inherent variability and limited expansion of primary seed cells. This study introduces a database-guided screening strategy integrating transcriptomic profiles, growth kinetics, and commercial availability to systematically identify high-performance human cell lines for matrix fabrication. By targeting cells with superior biosynthetic and proliferative traits, we demonstrate that a representative cell line, Hs 578 T, can produce ECM-rich substrates with enhanced efficiency and consistency compared to conventional fibroblasts. Under optimized conditions, Hs 578 T cells formed protein-rich cell sheets processed into ECM hydrogels retaining native complexity and pro-vascular bioactivity. This workflow enables rational seed cell prioritization, bridging cell sheet technology with the efficient fabrication of bioactive human ECM materials.
Impaired angiogenesis is a major cause of delayed healing in age-related bone defects, and dysfunction of the pro-angiogenic paracrine activity of senescent bone marrow mesenchymal stem cells (BMSCs) contributes substantially to this vascular deficiency. Here, we synthesised a tannic acid-derived nanocarbon (TANC) and investigated whether it could promote angiogenesis by restoring the pro-angiogenic paracrine function of senescent BMSCs. In an aged rat calvarial defect model treated with locally implanted TANC-loaded GelMA hydrogels, TANC significantly increased blood perfusion, CD31-positive vessel density, and VEGF expression. In vitro, conditioned medium from TANC-treated senescent BMSCs markedly enhanced endothelial proliferation, migration, tube formation, and angiogenesis-related marker expression, whereas direct TANC treatment showed little effect. Transcriptomic screening and functional validation identified Lama2 as a key paracrine mediator regulated by TANC. Lama2 knockdown in vitro and Lama2 neutralisation in vivo both markedly attenuated the pro-angiogenic effect. Mechanistically, Lama2 preferentially interacted with integrin α3β1 on endothelial cells and activated downstream PI3K/AKT signalling. Collectively, these findings show that TANC restores the pro-angiogenic paracrine function of senescent BMSCs through the Lama2/integrin α3β1/PI3K/AKT axis and represents a promising biomaterial-based strategy for age-related bone defects with impaired vascularisation.
Craniomaxillofacial bone defects complicated by implant-associated infection require scaffolds that combine structural support, localized therapeutic delivery, and antibacterial function. Polymer coatings can modify scaffold-drug interactions and surface wettability but controlling cumulative drug release and early burst behavior simultaneously remains challenging with a single coating layer. Here, silver-doped 3D-printed tricalcium phosphate (Ag-TCP) scaffolds were modified with a sequential polydopamine (PD) - polycaprolactone (PCL) coating to regulate vitamin D₃ (VD3) delivery and determine whether coating-mediated osteogenic effects persist under static and dynamic culture conditions. PD increased surface hydrophilicity and raised cumulative VD3 release from approximately 18% to 25% over 35 days but also increased early burst release. Addition of a 1 wt% PCL overlayer reduced the initial burst by 1.3-fold while maintaining sustained release behavior. In static osteoblast culture, PD-PCL-coated scaffolds increased cell viability by 2.5-fold by day 11 and elevated alkaline phosphatase activity by 1.3-fold compared with uncoated Ag-TCP. Under dynamic recirculating culture, the coated scaffolds maintained enhanced osteoblast viability, producing a 2-fold increase compared with uncoated Ag-TCP. These findings demonstrate that sequential PD-PCL coatings provide a tunable strategy for controlled VD3 delivery from 3D-printed Ag-TCP scaffolds while supporting improved osteoblast response across static and fluid-dynamic culture environments.
