Biofabrication最新文献

Liposomes, as one of the most promising and rapidly evolving drug delivery systems, are highly valued for their biocompatibility, ability to encapsulate diverse drugs, controlled release, and targeted delivery, offering enhanced therapeutic effects with reduced toxicity. However traditional methods for synthesizing liposomes still exhibit problems such as uncontrollable particle size and uneven distribution, reducing passive targeting efficiency and compromising treatments In present study, we introduce a novel alternating current electrokinetic mixing-assisted micro-synthesis method for liposome production, utilizing a novel custom (mold-extraction) approach to fabricate a 3D-structured microfluidic chip with parallel electrodes along both sides of the channel. Unlike traditional methods, where etched thin electrodes often result in non-uniform electric fields and leakage, the present method enables the placement of 3D electrodes with channel thickness, minimizes electrode distance, and allows for the generation of a strong, uniform electric field at low voltages. Consequently, controllable ultra-fast active mixing is achieved, resulting in the controlled and adjustable synthesis of liposomes with uniform size distributions. The effects of flow rate,E(electric field intensity), and frequency on the synthesis of liposomes were investigated. Additionally, studies demonstrated that drug encapsulation efficiency can be precisely controlled by modulating the applied electric field, a capability that was further validated through cellular experiments. This study presents a straightforward and adjustable approach for the precise synthesis of liposomes, which can be utilized to develop customized drug delivery systems.

The fabrication of anatomically accurate, cellularized heart valve substitutes remains a significant challenge in tissue engineering, particularly for pediatric and patient-specific applications. While three-dimensional (3D) bioprinting enables the creation of complex geometries, it often compromises cell viability and lacks the precision required for small-scale constructs. In this study, we present a high-fidelity, reproducible molding technique using 3D-printed sugar glass molds to engineer custom, alginate-based hydrogel cellularized heart valves. Human adipose-derived stromal cells (ASCs) were used as the cell source due to their accessibility and regenerative potential. This approach overcomes the limitations of conventional molding and bioprinting by enabling the reproduction of intricate anatomical features, including the sinuses of Valsalva, which are critical for physiological hemodynamics. The molding method maintains high cell viability (>90%) at the time of fabrication and the process supports both scalability and automation. Sugar glass molds for valve sizes from 16 to 26 mm inner diameter were printed with 90% of the mold surface within a ±0.3 mm deviation of the reference computer-aided design model. Cellularized valves cultured in a custom perfusion bioreactor retained structural integrity and cell viability over a 14 d period. This biofabrication strategy offers a promising platform for engineering patient-specific heart valves and also lays the groundwork forin vitrodisease modeling, including valve mineralization, using living cells such as ASCs.

The growing demand for physiologically relevant human brain models has driven the development of advanced three-dimensional (3D) systems that can recapitulate key aspects of neural architecture and function. Traditional two-dimensional cultures and animal models fall short in reproducing the structural complexity, cellular diversity, and species-specific characteristics of the human central nervous system. In this review, we provide a comprehensive overview of state-of-the-art scaffold-free and scaffold-based strategies for generating 3D human brain models, with particular emphasis on those derived from pluripotent stem cells. Scaffold-free systems-such as spheroids, organoids, and assembloids-exploit the intrinsic self-organizing capacity of neural cells to recreate spatially and temporally regulated interactions observed during development. Conversely, scaffold-based models utilize biomaterials, including hydrogels and decellularized matrices, to replicate the physical and biochemical properties of the brain microenvironment, providing enhanced control over tissue architecture and reproducibility. A wide range of fabrication methods is discussed, and for each, we assess key features, strengths, and limitations, with particular attention to scalability, reproducibility, and biological relevance. Overall, this review is intended to serve as a practical and well-structured reference for researchers seeking to select or develop the most appropriatein vitro3D brain model for specific applications in neural development and disease modelling.

Peptides are essential bioactive compounds with broad applications in nutraceuticals, pharmaceuticals, cosmetics, and materials. As their applications continue to grow, the development of efficient and sustainable synthesis methods has emerged as a major focus of research. This review provides a comprehensive summary of the primary methods for peptide synthesis, including biosynthesis, classical solution-phase peptide synthesis (CSPS), solid-phase peptide synthesis (SPPS), liquid-phase peptide synthesis (LPPS), and emerging technologies such as transition metal catalysis, photocatalysis, and electrochemistry. Special emphasis is placed on the recent advancements in CSPS, SPPS, LPPS, and emerging technologies, with a particular focus on the integration of green chemistry principles into SPPS and emerging techniques. These methods not only involve the construction of peptide molecules but also the conversion of linear peptides into cyclic peptides. Through an in-depth review of the relevant literature, this paper outlines the fundamental principles, advantages, and limitations of each method, while exploring their potential to enhance synthesis efficiency, reduce production costs, and minimize environmental impact. This study aims to explore innovative pathways in peptide synthesis, drive its applications in biomedicine and materials chemistry, and advocate for the deep integration of green and sustainable principles into research and practice.

Bone metastases account for the majority of deaths from breast cancer (BCa) and produce painful osteolytic lesions through osteoclast hyperactivation. However, the reciprocal interaction between BCa cells and the metastatic bone niche in regulating the osteolytic process remains largely unknown. Therefore, we examined the effect of bone microenvironmental cues on the acquisition of osteomimetic features (expression of bone-cell markers to bypass immune monitoring) by MDA-MB-231 triple-negative BCa cells. Four different hydroxyapatite (HA) particles in the micron size range (3-25µm) with varying physiochemical characteristics were combined with type I collagen matrix. This produced composites to emulate the secondary bone metastasis niche at the bone marrow-cortical bone interface we termed the 'bone bioengineered interfaces' (BBIs). We showed that passive calcium dissolution from HA crystals in the BBIs is a critical bio-determinant related to MDA-MB-231 cells' osteomimicry and osteoclastogenesis of THP-1 monocytic cells in bone metastasis. These findings provide novel insights into the mechanisms of the reciprocal interaction between BCa cells and the metastatic bone microenvironment and pave the way for the potential use of more effective and environmentally friendly approaches for personalised medicine platforms and tailored therapeutic strategies.

Bioprinting, a technology with the potential to support long-term space missions, offers medical solutions for human settlements on the Moon and Mars. Moreover, 'green bioprinting' presents a promising approach to address terrestrial environmental challenges. Effective and cost-efficient implementation of this technology beyond the Earth requires leveragingin situresources on celestial bodies. Consequently, this study examines the integration of Lunar and Martian regolith into bioprintable hydrogels as mechanically stabilizing and protective components as well as nutrient sources. Hydrogel blends composed of alginate and methylcellulose were supplemented with regolith simulants. Rheological characterization revealed maintenance of shear thinning and shear recovery properties, ensuring optimal printability. In regards to cultivation of microalgae, the ion release/uptake of the regolith simulants in culture medium was investigated, indicating that regolith has potential to serve as nutrient source. The microalgaChlorella vulgarisand bacteriaButtiauxella sp. MASE-IM-9 andSalinisphaera shabanensiswere bioprinted in regolith-based inks. Results demonstrate that the microalgae maintained their photosynthetic efficiency in regolith-containing bioinks during cultivation, exhibiting high viability and growth. The bacteria exhibited an enhanced resistance to desiccation as well as temperature and radiation stress when regolith simulants were present in the hydrogels. This study confirms the feasibility of employing Lunar and Martian regolith simulants in bioinks for green bioprinting and bacterial bioprinting. Such an approach could minimize the volume of stored printing materials and culture media, optimizing rocket transport capacity.

Developing a biomimetic culture system is crucial for the efficient maintenance and expansion of rare hematopoietic stem and progenitor cells (HSPCs)in vitro. This advancement can significantly enhance the application of HSPC-based transplantation therapies and support the manufacturing of bone marrow (BM) organoids. Traditional two-dimensional culture systems fall short in replicating the interactions between cultured cells and the hematopoietic niche, resulting in excessive reactive oxygen species (ROS) production and triggering HSPC differentiation. In response, we have developed an innovative three-dimensional (3D) culture system using a novel composite hydrogel, GelMA-PVA-TSPBA (GelMA-P-T), which offers excellent biocompatibility and ROS-scavenging properties. When murine and human embryonic stem cell (hESC)-derived HSPCs were cultured in this new hydrogel, they exhibited low ROS levels and showed enhanced self-renewal and expansion capabilities. Importantly, incorporating niche-related cells into the composite hydrogel created a 3D engineered BM microenvironment that significantly improved the self-renewal and expansion of HSPCs. Additionally, the biomimetic niche comprising GelMA-P-T and various stromal cells effectively inhibited the differentiation of murine and hESC-derived HSPCs. Mechanistically, compared with GelMA, the low ROS microenvironment fostered by GelMA-P-T significantly enhanced mitochondrial function in HSPCs, supporting the expression of HSPC-related genes and inhibiting blood cell differentiation. Our findings suggest that the GelMA-P-T-based biomimetic culture system has the potential to advance the clinical application of expanded HSPCs and accelerate the development of BM organoid technology.

Smooth muscle cells (SMCs) derived from induced pluripotent stem cells (iPSCs) have been used for scaffold-free structures; however, their use in regenerated organs is rare and not well established. The induction of mesenchymal stem cells (MSCs) via neural crest cells (NCCs) from iPSCs offers advantages such as a large-scale cell stock. While research has progressed on the chondrogenic differentiation and regenerative medicine applications of cartilage derived from human iPSC-derived MSCs via a NCCs lineage (iNC), studies on smooth muscle, a critical tracheal component alongside cartilage, remain limited. In this study, we aimed to establish a method for generating airway smooth muscle tissue constructs using human iNCMSCs, assess their contractile function, and evaluate their regenerative potential in tracheal cartilage defects. iNCMSCs were cultured for 28 d in Dulbecco's Modified Eagle Medium (DMEM) with fetal bovine serum (FBS), with one group receiving transforming growth factor beta 1 (TGFβ1, DMEM-TGFβ1 group) and the other group without TGFβ1 (DMEM group). SMCs markers was assessed using immunofluorescence staining. The tissue constructs were bio-3D printed using spheroids from the DMEM-TGFβ1 group and transplanted as smooth muscle patches into full-thickness defects in the rats' tracheas. The DMEM-TGFβ1 group showed strong expression of SMCs markers such asα-smooth muscle actin, calponin, and myosin heavy chain. After 28 d post-transplant, histological evaluation confirmed graft engraftment, adequate blood flow, and epithelial layer extensions from the recipient tissues, along with well-maintained tracheal structures. This study demonstrated the feasibility of using iPSC-derived iNCMSCs to generate bio-3D printed smooth muscle constructs for tracheal regeneration. Our findings support the potential of this strategy as a novel approach for airway reconstruction, offering a scaffold-free cell-based platform for future clinical applications in tissue engineering for airway regeneration.

The next generation of three-dimensional (3D) micro-additive manufacturing (AM) bioelectronics requires inks that simultaneously combine high electrical conductivity, biocompatibility, electrochemical stability, and compatibility with 3D processing. However, most existing inks fail to meet all these criteria, with processability and repeatability remaining major bottlenecks. This challenge is particularly serious in printed electronics technologies, such as Aerosol Jet® Printing (AJ®P), for which commercially available formulations tailored to specific applications are still scarce. Here, we present a novel poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)-based ink incorporating polyethylene glycol, ethylene glycol, and carboxymethyl cellulose to obtain a composite that fulfils all requirements, being conductive, processible by AJ®P and biocompatible. The formulation exhibits high conductivity (σ= 495.29 S · cm^-1), electrochemical stability, and biocompatibility with both human fibroblasts and iPSC-derived neural stem cells. Its low viscosity (μ= 7.93 mPa · s) enables precise and repeatable AJ®P fabrication while supporting controlled, high-resolution 2D patterning and 3D microfabrication with aspect ratios up to 9. Dense or hollow microarrays of 24 flexible pillars (diameter ⩾ 35μm; elastic modulus = 3.1 × 10⁶Pa per pillar) can be fabricated within 10 min, without masks or supporting materials. This work focuses on the material and process optimisation study of a customisable bioink for AJ®P in 3D micro-AM bioelectronics, with potential applications in 3D microelectrode arrays, biosensors, tissue engineering.

Cardiac tissues derived from human-induced pluripotent stem cells (hiPSCs) are a promising platform for physiological modeling and drug screening. Among the various strategies used to recreate thein vivoenvironment for cardiac tissues, mechanical stress has been widely studied for its diverse effects. However, the effects of cellular structure and mechanical loading on the function of scaffold-free tissues remain unclear. Scaffold-free cardiac tissues were fabricated by layering hiPSC-derived cardiomyocytes onto human cardiac fibroblasts in temperature-responsive culture dishes. These tissues were harvested and cultured under fixed tissue lengths (representing the degree of shrinkage) and afterloads (resistance against contraction) in a newly designed culture and measurement device capable of measuring the tensional force under various tissue lengths and afterloads. The contractile force, tissue stiffness, morphology, and gene expression were evaluated. Double-layered cells formed in a ring shape were mounted onto the device in a bundle shape, enabling the measurement of contractile forces generated by spontaneous beating. Additionally, increased contractile force was observed in response to both stretching andβ-adrenergic stimulation. The contractile force was influenced by the degree of shrinkage. Tissues set at shorter lengths (greater shrinkage) exhibited significantly reduced force and did not recover by day 7. Additionally, tissues cultured under higher afterloads displayed significantly increased contractile forces and stiffness. Our findings demonstrate that both the initial shrinkage and afterload magnitude critically influence the mechanical function of scaffold-free cardiac tissues. These results highlight the importance of controlling the mechanical environment in scaffold-free tissue engineering.