Search Results (154)

Inspired by natural scaffolds, artificial scaffolds have garnered significant attention in recent years. Compared with synthetic scaffolds such as organic and polymer scaffolds, biological scaffolds from the foundational biomolecules nucleic acids (DNA/RNA) and proteins demonstrate distinct advantages in the assembly of inorganic nanoparticles and proteins, as well as in drug delivery. These advantages stem from their exquisite spatial structures, genetically encoded programmability, and their favorable biocompatibility, which is attributed to natural building blocks and degradable backbones that minimize long-term cytotoxicity. The intrinsic properties and structural symmetry of biomacromolecules as building blocks often determine the properties of the corresponding assemblies, and thus greatly influence their functions. In this review, we classify bottom-up constructed biological scaffolds according to these two primary constituent classes (nucleic acids and proteins) to examine their framework structures and key features. We also discuss the relevant applications of artificial bioscaffolds. As an emerging class of nanomaterial with precise structures and genetic programmability, biological scaffolds hold significant promise for future development. Full article

Culturing cells and micro-tissue samples in 3D bio-scaffolding structures is gaining popularity; however, precise control of tissue micro-environment in such systems remains challenging. We describe a family of new hybrid bio-scaffolds with 3D O₂-sensing ability, produced by simple means from readily available bio-scaffolding and O₂-sensing materials. Three different types of phosphorescent O₂-sensing materials—polymeric microparticles (MPs), supramolecular probe MitoXpress and nanoparticulate probes NanO2 and Nano-IR (NPs)—were integrated in Matrigel and agarose scaffolding materials and evaluated. Key working characteristics of such hybrid scaffolds, including heterogeneity, stability, cytotoxicity, optical signals and O₂-sensing properties, ease of fabrication and use, were compared. The results show superiority of the Matrigel hybrids with NanO2 and Nano-IR probes. Demonstration experiments were conducted with HCT116 cells and individual spheroids derived from these cells, culturing them in the Matrigel–NP hybrid scaffolds and monitoring oxygenation and local O₂ gradients on a time-resolved fluorescence plate reader and by phosphorescence lifetime imaging microscopy (PLIM). Full article

Tissue decellularization aims to obtain bioscaffolds for regenerative applications by removing all cellular components while preserving the extracellular matrix (ECM) architecture. Although decellularization removes the majority of linear nuclear DNA (nDNA), residual amounts remain detectable. However, the fate of circular mitochondrial DNA (mtDNA) after decellularization has not yet been reported. Cell death or injury can cause the release of mtDNA, which is resistant to breakdown by exonucleases. Extracellular mtDNA acts as a damage-associated molecular pattern (DAMP) that can trigger immune responses. The aim of this study is to assess the presence of residual mtDNA in the liver, bile duct, and vascular scaffolds after decellularization and whether this causes inflammatory responses in macrophages. Decellularized tissues showed a marked reduction in total DNA content well below the threshold of 50 ng/mg tissue. However, in liver and vascular scaffolds, a relative increase in the mtDNA:nDNA ratio was detected in the remnant DNA fraction. Residual mtDNA in bioscaffolds acted as DAMPs causing macrophage activation, as shown by increased cell proliferation and cytokine production. Strategies to further reduce remnant mtDNA were tested. We found that treatment with the endonuclease enzyme HpaII was effective in degrading residual mtDNA. Importantly, mtDNA removal resulted in a significantly reduced macrophage activation. In conclusion, our study shows that mtDNA is relatively resistant to the decellularization procedure and can act as a DAMP in bioscaffolds. This underscores the importance of removing mtDNA from decellularized bioscaffolds to improve the immunocompatibility for biomedical applications. Full article

Background: Three-dimensional (3D) cell cultures are increasingly recognized as effective models for studying diseases and developing cell therapies. In the endocrine pancreas field, organoids/spheroids derived from human islet cells enable advances in diabetes research, drug screening, and tissue engineering. While various 3D culture methods exist, approaches such as magnetic bead-assisted aggregation remain underexplored for endocrine pancreatic cells. Additionally, the use of biological scaffolds, especially those derived from decellularized pancreatic extracellular matrix, provides a biomimetic environment that promotes adhesion, proliferation, and functionality of pancreatic cells. This study presents a protocol for magnetic bead-guided 3D culture of human islet cells within decellularized pancreatic scaffolds. Methods: Human pancreas from adult brain-dead donors was harvested for both islets’ isolation processing and decellularization to generate an acellular pancreatic bioscaffold. Primary human pancreatic islets were first grown in two-dimensional adherent cultures, then enzymatically harvested from the surface and reassembled into three-dimensional clusters using different initial cell amounts (small clusters 0.5 × 10⁴–1 × 10⁴ and larger clusters 2.5 × 10⁴–5 × 10⁴ cells) and then placed within acellular pancreatic slices of different thickness, namely 50 and 90 μm. Optic microscopic examination, scanning electron microscopy analysis, and assessment of insulin and lactate dehydrogenase (LDH) levels were used to evaluate these 3D islet-like cluster cultures. Results: We report the establishment of 3D cultures derived from primary pancreatic islet cells using a magnetic approach in a remarkable 18 h period for the complete formation of 3D clusters. The small clusters (0.5 × 10⁴–1 × 10⁴ cells) exhibited a faster attachment to the acellular matrix, with cells visibly spreading outside the cluster interacting with the bioscaffold slice, when compared to the larger clusters (2.5 × 10⁴–5 × 10⁴ cells). These cells continued to produce insulin, and no statistically significant differences in LDH levels were found under these different conditions. Conclusions: Here, we demonstrate that a magnetic bead-based protocol can be successfully applied to endocrine pancreatic cells, enabling the rapid formation of compact, viable, and functional 3D structures. Despite limitations such as higher cost and prolonged retention of magnetic particles, the approach supports size-dependent interactions with decellularized pancreatic scaffolds. These findings are valuable for researchers designing experiments tailored to specific objectives and underscore the potential of this platform for advancing diabetes research and pancreatic tissue engineering. Full article

Milk is an essential component of the diet. Among its diverse molecular constituents, it contains nanoscale entities, known as extracellular vesicles (EVs), which play a pivotal role in intercellular communication. In particular, milk-derived EVs (MEVs) influence intestinal homeostasis by mitigating inflammatory responses, modulating gut microbiota composition, and contributing to epithelial integrity preservation and restoration. Currently, there are no information regarding their impact on intestinal connective tissue. Here, we investigate bovine MEV effects on the porcine gut stromal compartment, exposing intestinal decellularized bio-scaffolds repopulated with primary intestinal stromal fibroblasts, to different MEV concentrations (10⁶, 10⁸, and 10¹⁰ particles/mL). We observed a dose-dependent effect of MEVs on stromal fibroblast proliferation rate at concentrations higher than 10⁶ particles/mL. In addition, when MEVs were used to pre-condition the decellularized intestinal bio-scaffolds prior to cell repopulation, fibroblast growth was further boosted. Overall, these findings suggest that MEVs may play a significant role in promoting tissue remodeling and repair. This activity appears particularly relevant for enhancing intestinal homeostasis and resilience, as stromal fibroblasts contribute to the maintenance of gut integrity, barrier function, and immune balance. Moreover, the data here presented suggests the possibility of using MEVs to develop serum-free, chemically defined culture media for the generation of advanced three-dimensional (3D) models and intestinal artificial organs. Full article

Organoids are three-dimensional multicellular structures that mimic key aspects of native tissues consisting ideal tools to study organ development and pathophysiology when incorporated in customized bioscaffolds. In vivo, the extracellular matrix (ECM) maintains tissue integrity and regulates cell adhesion, migration, differentiation, and survival through biochemical and mechanical signals. Tissue-derived decellularized extracellular matrix (dECM) can preserve organ-specific biochemical signals and cell-adhesive motifs, creating a bioactive environment that supports physiologically relevant organoid growth. 3D bioprinting technology marks a transformative phase in organoid research by enhancing the structural and functional complexity of organoid models and expanding their application in pharmacology and regenerative medicine. These systems enhance tissue modeling and drug testing while adhering to the principles of animal replacement, reduction, and refining (3Rs) in research. Remaining challenges include donor variability, limited mechanical stability, and the lack of standardized decellularization protocols that can be addressed by adopting quality and safety metrics. The combination of dECM-based biomaterials and 3D bioprinting holds great potential for the development of human-relevant, customizable, and ethically sound in vitro models for regenerative medicine and personalized therapies. In this review, we discuss the latest (2021–2025) developments in applying extracellular matrix bioprinting techniques to organoid technology, presenting examples for the most commonly referenced organoid types. Full article

This work characterizes hybrid hydrogels prepared via the combination of natural and synthetic polymers. By incorporating a biocompatible compound, poly(ethylene glycol) diacrylate (PEGDA, M_n = 400), into alginate and carboxymethyl cellulose (CMC)-based hydrogels, the in situ UV crosslinking of these materials was assessed. A custom direct-write (DW) 3D bioprinter was utilized to prepare hybrid hydrogel constructs and scaffolds. A control sample, which consisted of 4% w/v alginate and 4% w/v CMC, was prepared and evaluated in addition to three PEGDA (4.5, 6.5, and 10% w/v)-containing hybrid hydrogels. Rotational rheology was utilized to evaluate the thixotropic behavior of these materials. Filament fusion tests were employed to generate bilayer constructs of various pore sizes, providing metrics for the printability and diffusion rate of hydrogels post-extrusion. Printability indicates the shape fidelity of pore geometry, whereas diffusion rate represents material spreading after deposition. Curing kinetics of PEGDA-containing hydrogels were evaluated using photo-Differential Scanning Calorimetry (DSC) and photorheology. The Kamal model was fitted to photo-DSC results, enabling an assessment and comparison of the curing kinetics for PEGDA-containing hydrogels. Photorheological results highlight the increase in hydrogel stiffness concomitant with PEGDA content. The range of obtained complex moduli (G*) provides utility for the development of brain, kidney, and heart tissue (620–4600 Pa). The in situ UV irradiation of PEGDA-containing hydrogels improved the shape fidelity of printed bilayers and decreased filament diffusion rates. In situ UV irradiation enabled 10-layer scaffolds with 1 × 1 mm pore sizes to be printed. Ultimately, this study highlights the utility of PEGDA-containing hybrid hydrogels for high-resolution DW 3D bioprinting and potential application toward customizable tissue analogs. Full article

In regenerative medicine, an engineered tissue is a composition of a sample of cells cultured on a spatially controlled medical device, called a biological scaffold (or just a bioscaffold). These devices are made of tissue-equivalent materials and represent the biological, mechanical, and spatial conditions in a specific type of human or animal tissue, becoming a possible way to replace damaged structures and develop artificial tissues or organs. Scaffolds with narrowly controlled characteristics—biological, mechanical and spatial properties—are vital for experiments mimicking in vivo conditions and in tissue regeneration scenarios. The aim of this narrative review is to identify and discuss the most important properties of these artificial constructs and the ways to achieve them via 3D printing-based technologies. Properties that can direct the development and differentiation of the cultured cells in a specific direction and ensure their biocompatibility and bioresorption, mechanical properties, spatial architecture, and porosity are discussed. The most common considerations in terms of the role of material selection, additives, and signal molecules and the appropriate spatially controlled manufacturing technologies for their assembly are covered, as are the radiological, biomechanical, and histological methods for their analysis. Finally, this paper highlights the challenges to the achievement of optimal scaffolds through additive manufacturing and gives suggestions for further research and development in this field. Full article

Corneal transplantation is often considered the last resort for severe corneal epithelial disorders, especially limbal stem cell deficiency (LSCD). Tissue engineering offers novel strategies to mitigate the shortage of corneal transplant donors. However, low cell viability and compromised functionality in tissue engineering represent a major challenge. In this review, we describe the key characteristics required for corneal epithelium bioscaffolds. We summarize the research progress centered on optimizing cell activity and functionality in the past 10 years from four key perspectives: the sourcing of cells, seed cell pretreatments, biomaterial optimization, and engineered culture system innovation. The sources, isolation, and induction methods of seed cells are described, and the advantages and disadvantages of existing clinical treatment methods are compared. Furthermore, we compare existing clinical therapies and summarize promising seed cell pretreatment strategies for the first time. Several innovative engineered cell culture systems are exhibited as well. We demonstrated how to preserve cell viability through bioscaffold stiffness modulation, topographic design, and application of innovative fabrication techniques. Finally, we propose a personalized and precise regeneration strategy based on high-resolution images, digital modeling, bioprinting, and machine learning. Full article

Background: The human acellular amniotic membrane (HAAM) is widely used as a decellularized bioscaffold in tissue engineering to promote wound healing, but its clinical application is limited by poor mechanical properties, rapid degradation, and handling difficulties. This study aimed to develop a modified amniotic membrane-based composite material loaded with vascular endothelial growth factor (VEGF) and the Notch signaling inhibitor N-[N-(3,5-difluorophenacetyl)-Lalanylhydrazide]-Sphenylglycine t-butyl ester (DAPT) to enhance wound healing by modulating macrophage polarization and cytokine secretion. Methods: VEGF-loaded gellan gum-hyaluronic acid (GG-HA) hydrogels (VEGF-GG-HA) and DAPT-loaded HAAM (DAPT-HAAM) were prepared and combined to form a novel composite material (VEGF-GG-HA & DAPT-HAAM). The morphology and microstructure of the materials were characterized using scanning electron microscopy. In vitro studies were conducted using the human monocytic cell line (Tohoku Hospital Pediatrics-1, THP-1) to evaluate the effects of the materials on cell viability, cytokine secretion, and protein expression. Assessments included CCK-8 assays, ELISA, quantitative real-time PCR, Western blot analysis, and immunohistochemical staining. Results: The composite material VEGF-GG-HA & DAPT-HAAM exhibited good biocompatibility and significantly promoted THP-1 cell proliferation compared to control and single-component groups. It enhanced the secretion of IL-10, TNF-α, TGF-β, MMP1, and MMP3, while suppressing excessive TGF-β overexpression. The material also modulated macrophage polarization, showing a trend toward anti-inflammatory M2 phenotypes while maintaining pro-inflammatory signals (e.g., TNF-α) for a balanced immune response. Conclusions: The modified amniotic membrane hydrogel composite promotes wound healing through a phased immune response: it modulates macrophage polarization (balancing M1 and M2 phenotypes), enhances cytokine and matrix metalloproteinase secretion, and controls TGF-β levels. These effects contribute to improved vascular remodeling, reduced fibrosis, and prevention of scar formation, demonstrating the potential for enhanced wound management. Full article

Pulmonary fibrosis (PF) is a progressive and fatal lung disease characterized by irreversible alveolar destruction and pathological extracellular matrix (ECM) deposition. Currently approved agents (pirfenidone and nintedanib) slow functional decline but do not reverse established fibrosis or restore functional alveoli. Multifunctional bioscaffolds present a promising therapeutic strategy through targeted modulation of critical cellular processes, including proliferation, migration, and differentiation. This review synthesizes recent advances in scaffold-based interventions for PF, with a focus on their dual mechano-epigenetic regulatory functions. We delineate how scaffold properties (elastic modulus, stiffness gradients, dynamic mechanical cues) direct cell fate decisions via mechanotransduction pathways, exemplified by focal adhesion–cytoskeleton coupling. Critically, we highlight how pathological mechanical inputs establish and perpetuate self-reinforcing epigenetic barriers to regeneration through aberrant chromatin states. Furthermore, we examine scaffolds as platforms for precision epigenetic drug delivery, particularly controlled release of inhibitors targeting DNA methyltransferases (DNMTi) and histone deacetylases (HDACi) to disrupt this mechano-reinforced barrier. Evidence from PF murine models and ex vivo lung slice cultures demonstrate scaffold-mediated remodeling of the fibrotic niche, with key studies reporting substantial reductions in collagen deposition and significant increases in alveolar epithelial cell markers following intervention. These quantitative outcomes highlight enhanced alveolar epithelial plasticity and upregulating antifibrotic gene networks. Emerging integration of stimuli-responsive biomaterials, CRISPR/dCas9-based epigenetic editors, and AI-driven design to enhance scaffold functionality is discussed. Collectively, multifunctional bioscaffolds hold significant potential for clinical translation by uniquely co-targeting mechanotransduction and epigenetic reprogramming. Future work will need to resolve persistent challenges, including the erasure of pathological mechanical memory and precise spatiotemporal control of epigenetic modifiers in vivo, to unlock their full therapeutic potential. Full article

Neural tissue injuries, including spinal cord damage and neurodegenerative diseases, pose a major clinical challenge due to the central nervous system’s limited regenerative capacity. Current treatments focus on stabilization and symptom management rather than functional restoration. Tissue engineering offers new therapeutic perspectives, particularly through the combination of electrospun nanofibrous scaffolds and mesenchymal stem cells (MSCs). Electrospun fibers mimic the neural extracellular matrix, providing topographical and mechanical cues that enhance MSC adhesion, viability, and neural differentiation. MSCs are multipotent stem cells with robust paracrine and immunomodulatory activity, capable of supporting regeneration and, under proper stimuli, acquiring neural-like phenotypes. This systematic review, following the PRISMA 2020 method, analyzes 77 selected articles from the last ten years to assess the potential of electrospun biopolymer scaffolds for MSC-mediated neural repair. We critically examine the scaffold’s composition (synthetic and natural polymers), fiber architecture (alignment and diameter), structural and mechanical properties (porosity and stiffness), and biofunctionalization strategies. The influence of MSC tissue sources (bone marrow, adipose, and dental pulp) on neural differentiation outcomes is also discussed. The results of a literature search show both in vitro and in vivo enhanced neural marker expression, neurite extension, and functional recovery when MSCs are seeded onto optimized electrospun scaffolds. Therefore, integrating stem cell therapy with advanced biomaterials offers a promising route to bridge the gap between neural injury and functional regeneration. Full article

Extracellular matrix (ECM) bioscaffolds have demonstrated therapeutic potential across a variety of clinical and preclinical applications for tissue repair and regeneration. In parallel, these scaffolds and their components have shown the capacity to modulate the immune response. Unlike synthetic implants, which are often associated with chronic inflammation or fibrotic encapsulation, ECM bioscaffolds interact dynamically with host cells, promoting constructive tissue remodeling. This effect is largely attributed to the preservation of structural and biochemical cues—such as degradation products and matrix-bound nanovesicles (MBV). These cues influence immune cell behavior and support the transition from inflammation to resolution and functional tissue regeneration. However, the immunomodulatory properties of ECM bioscaffolds are dependent on the source tissue and, critically, on the methods used for decellularization. Inadequate removal of cellular components or the presence of residual chemicals can shift the host response towards a pro-inflammatory, non-constructive phenotype, ultimately compromising therapeutic outcomes. This review synthesizes current basic concepts on the innate immune response to ECM bioscaffolds, with particular attention to the inflammatory, proliferative, and remodeling phases following implantation. We explore how specific ECM features shape these responses and distinguish between pro-remodeling and pro-inflammatory outcomes. Additionally, we examine the impact of manufacturing practices and quality control on the preservation of ECM bioactivity. These insights challenge the conventional classification of ECM bioscaffolds as medical devices and support their recognition as biologically active materials with distinct immunoregulatory potential. A deeper understanding of these properties is critical for optimizing clinical applications and guiding the development of updated regulatory frameworks in regenerative medicine. Full article

Micellar or mycelial membranes from medicinal mushrooms are self-growing fibrous polymeric biocomposites that are biocompatible, biodegradable, cost-effective, and environmentally friendly. In this study, the cultivation process for the medicinal mushrooms Ganoderma lucidum and Pleurotus ostreatus has been optimized via submerged cultivation to maximize growth and promote the formation of micellar membranes with high water-absorption capacity. Optimal growth conditions were achieved at an alkaline pH in a medium containing malt extract for G. lucidum, while for P. ostreatus, these were in a glucose-enriched medium. The hydrophilic underside of the micellar membranes led to a high-water uptake capacity. These membranes exhibited a broad spectrum of functional groups, thermal stability with decomposition temperatures above 260 °C, and a fibrous and porous structure. The micellar membranes from both mushrooms were additionally functionalized with mango peel extract (MPE), resulting in a uniform and gradual release profile, which is an important novelty. They also showed successful antimicrobial activity against Escherichia coli and Staphylococcus aureus growth. MPE-functionalized micellar membranes are, therefore, innovative biocomposites suitable for various biomedical applications. As they mimic the extracellular matrix of the skin, they are a promising material for tissue engineering, wound healing, and advanced skin materials applications. Full article

Gelatin methacrylate (GelMA) microgels serve as promising bioscaffolds for tissue engineering and drug screening. However, conventional solid GelMA microgels often exhibit limited mass transfer efficiency and provide insufficient protection for embedded cells. In this study, we developed a droplet-based microfluidic platform to fabricate core–shell structured GelMA microgels. This system enabled precise control over microgel size and core-to-shell ratio by modulating flow rates. Encapsulation of A549 cells within these core–shell microgels preserved cellular viability and facilitated the formation of three-dimensional tumor spheroids. These outcomes confirmed both the protective function of the core–shell architecture during encapsulation and the overall biocompatibility of the microgels. The developed GelMA core–shell microgel system presents considerable applicability in research domains such as organoid modeling and high-throughput pharmacological screening. Full article