Multifunctional integrated hydrogels have emerged as advanced biomaterials that integrate diverse functional properties, including bioactivity, mechanical adaptability, controlled drug release, and electrical/magnetic responsiveness, exhibiting substantial potential in tissue regeneration and repair. These hydrogels provide a versatile platform to mimic the complex microenvironment of native tissues, thereby facilitating cell proliferation, differentiation, and tissue remodeling. Despite rapid progress in their design and development, optimizing performance for specific tissues (e.g., bone, cartilage, skin, nerve, myocardium) remains challenging. Current research focuses on innovative design strategies and the incorporation of key functional modules to tailor hydrogels for targeted regenerative applications. Moreover, translating these materials from bench to bedside requires overcoming barriers related to biocompatibility, scalability, regulatory approval, and long-term functional stability. This review comprehensively summarizes recent advances in multifunctional integrated hydrogels, highlights their applications across different tissue regeneration scenarios, and critically evaluates translational challenges. By synthesizing cutting-edge findings, this work aims to guide the development of next-generation smart tissue engineering scaffolds and accelerate their clinical adoption, ultimately advancing regenerative medicine.

Although embryonic chondrogenesis follows conserved developmental stages across mammalian species, the rate of this process varies significantly. We hypothesized that these varying developmental rates could be normalized and modeled by aligning key developmental milestones of articular cartilage: mesenchymal condensation, chondrogenic differentiation, joint interzone formation, cavitation, and primary ossification center formation. A mathematical model was developed in MATLAB by fitting the developmental curves of these key stages in mice, rats, pigs, horses, and humans. Among various mathematical models, a sigmoid curve model demonstrated the best fit, with the highest R[2] (0.98 ± 0.02) and lowest residual norm (0.36 ± 0.21) after normalizing for gestation period and femoral condylar width to account for species-specific differences. The model's high predictive accuracy (R[2] = 0.98) was further validated using data from rabbits, canines, and sheep. By differentiating the developmental curve equation, we determined the developmental rate for each species. Our results indicate that embryonic chondrogenesis occurs within a relatively narrow window of gestation (11-32%), with rodents exhibiting faster rates than larger animals. This study presents the first mathematical model to quantitatively align embryonic chondrogenesis across mammals. This model has the potential to fill gaps in developmental timelines through rational calculation and by improving the precision of developmental timing, factors that have often been overlooked in the field. As a pioneering effort, this work opens new avenues for cross-species alignment and enhances the accuracy of data related to embryonic chondrogenesis.Impact Statement As the first mathematical model to align chondrogenesis across different mammals, this work has the potential to enhance the consistency and accuracy of data from various species by correcting inaccuracies and supplementing missing information.

Hematopoietic stem and progenitor cells (HSPCs) are precisely organized within specialized bone marrow niches containing hematopoietic and nonhematopoietic cell types. Physiologically accurate human models of this niche environment that include functional HSPCs have been lacking until recently. Using induced pluripotent stem cells (iPSCs) grown in mixed-matrix hydrogels, vascularized three-dimensional human bone marrow organoids (hBMOs) can now be generated that contain mesenchymal, endothelial, and hematopoietic cells, all vital components of the bone marrow niche. While hBMOs have been shown to support engraftment of normal and malignant cells, there are numerous opportunities to use hBMOs for developing a wider experimental toolkit to test gene functions and stress responses. Here, we establish two new applications for the hBMO platform. First, we demonstrate successful engraftment of gene-edited CD34[+] cells from healthy donors, enabling direct investigation of gene-specific effects on human hematopoiesis in a defined microenvironment. Gene-edited engrafted HSPCs are maintained in hBMOs for 7 days and undergo multilineage differentiation. Second, we adapted a method to induce stress erythropoiesis-a response to acute anemia in mice and humans-in hBMOs, resulting in robust expansion of immunophenotypically defined hematopoietic progenitors and erythroid populations. These two advances expand the laboratory uses for hBMOs and establish this system as a versatile platform for studying human hematopoiesis and erythropoiesis, stress responses, and gene functions within a physiologically relevant bone marrow microenvironment.

Artificial intelligence (AI) is increasingly applied to bioink formulation and bioprinting process control in tissue engineering (TE). Yet, translational progress remains constrained by small datasets, limited cross-platform validation, and weak links between computational predictions and biological outcomes. This review critically evaluates experimentally validated AI applications across scaffold-based bone regeneration, spanning materials design, fabrication control, and biological assessment. Physics-informed models are often more robust and generalizable than purely data-driven approaches, whereas transfer learning remains challenging due to variability in cellular responses and fabrication conditions. To address gaps in existing reporting standards, to address gaps in current reporting recommendations, we propose the AI-TE reporting framework, incorporating TE-specific requirements for biological validation, fabrication documentation, and translational readiness. Impact StatementDespite the rapid growth of AI-driven scaffold design for bone regeneration, reproducibility, and validation remain insufficiently addressed across current studies. This review identifies key methodological gaps and synthesizes practical validation and reporting priorities to improve reliability and translational relevance.

Normothermic machine perfusion (NMP) has emerged as a new technique for organ storage before liver transplantation, making viability testing of the organ feasible and possibly allowing for reconditioning of marginal liver grafts. Erythrocytes form a substantial component in the composition of NMP perfusates. The optimal hematocrit (HCT) for preserving organ function during NMP and the effects of the HCT on metabolic graft function and parameters commonly used to determine organ viability are still unclear. We retrospectively analyzed our rat NMP database of 123 perfusions and identified a possible link between HCT and liver damage parameters in 34 cases following a dual perfusion protocol. To further investigate this relationship, we perfused a total of 16 rat livers for 6 h each in our rat liver NMP setup with four different HCTs at 10%, 16%, 22%, and 28%. We performed blood gas analysis and measured common viability and damage parameters such as bile production, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). In addition, histological analysis, as well as enzyme-linked immunosorbent assay and colorimetric assay analysis for reactive oxygen species, glycogen content, and hypoxia-inducible factor (HIF), was performed. The perfusate HCT significantly impacted ALT and LDH levels during NMP of rat liver grafts, with lower HCT values corresponding to decreased damage parameters. We investigated differentiating oxygenation levels and identified a possible cause for our observations in HIF-1α stabilization in lower HCT groups. Furthermore, we demonstrate that HCT affects key viability parameters such as lactate, pH levels, and bile production. Our findings illustrate the importance of adequate HCT levels during NMP and propose mechanisms influencing the perfusion outcome.Impact StatementNormothermic machine perfusion (NMP) is becoming an increasingly important tool in liver transplantation. We here show in an exploratory setting the importance of an adequate hematocrit for the outcome of liver graft perfusion and its importance in defining hepatic viability parameters during NMP.

Bone regeneration presents a significant clinical challenge due to the complex interplay between biological processes and the local mechanical environment. While polymeric scaffolds are widely utilized for their tunable physicochemical properties, traditional designs often fail to replicate the dynamic mechanical cues required for optimal tissue remodeling. This review critically examines the mechanobiological design of bioinspired polymeric scaffolds. We first categorize native bone mechanics and the role of mechanical stimuli-such as stiffness, fluid shear, and stability-in regulating the fracture healing cascade. We then bridge these biological principles with advanced fabrication strategies, analyzing how natural, synthetic, and composite polymers can be engineered to mimic the hierarchical stiffness and bioactivity of native bone. Furthermore, we discuss the role of computational modeling (e.g., Finite Element Analysis) in predicting scaffold performance and highlight emerging technologies, including 4D printing and piezoelectric scaffolds, which offer time-dependent and mechano-electrical adaptability. Finally, we address current barriers to clinical translation and propose future directions for mechanically adaptive systems that actively guide regeneration.

Urethral strictures can cause significant discomfort and progressive urinary tract damage if left untreated. Current reconstructive options, including urethral resection and buccal mucosa grafting, are associated with several limitations such as donor-site morbidity, limited tissue availability, and variable long-term outcomes. To address these challenges, we developed a novel multilayered 3D-bioprinted urethral construct designed to closely mimic the native urethral architecture. Using an Integrated Tissue and Organ Printing System (ITOP) equipped with a rotating mandrel, tubular urethral constructs were fabricated with distinct layers consisting of urothelial cells (UC), basement membrane (BM), smooth muscle cells (SMC), and supportive polycaprolactone (PCL). Autologous UC and SMC isolated from urinary bladder tissue were incorporated into a fibrinogen-based hydrogel bioink. Following in vitro maturation, the constructs were evaluated using viability assays, immunohistochemistry, and biomechanical testing. Live/Dead staining demonstrated an average cell viability of 75% for both UC and SMC populations. Immunostaining confirmed appropriate localization of the different cell types within their respective layers. Tensile testing showed that constructs matured for 14 days developed stable and elastic tissue-like mechanical properties. To further improve construct handling and structural integrity, horizontal reinforcement bands were incorporated into the PCL layer. Using this approach, 4 cm-long and 0.5 cm-diameter urethral constructs with native-like multilayered organization were successfully fabricated. This novel 3D-bioprinting strategy demonstrates strong potential for generating customizable and biologically relevant urethral grafts for future reconstructive applications. Ongoing in vitro optimization and planned in vivo evaluation in a porcine model aim to further validate the structural and functional performance of the construct and support future clinical translation for urethral and other tubular tissue reconstruction.

Skeletal muscle tissue engineering (SMTE) is a rapidly evolving field with applications spanning regenerative medicine, disease modeling, drug screening, and biohybrid robotics. Effective SMTE requires scaffolds that reproduce the anisotropic architecture and mechanical properties of native muscle while supporting macroscale tissue formation. Decellularized tissues are strong candidates; however, existing approaches face key limitations. Whole-muscle decellularization requires complex perfusion systems and often fails to fully clear the tissue core. In contrast, minced-tissue processing completely disrupts native architecture and necessitates technically demanding reconstruction. As a result, producing long, continuous scaffolds needed to model or restore physiologically relevant muscle units remains challenging. Here, we present an intermediate strategy that enables the fabrication of long, aligned scaffolds from native muscle bundles. Bundles exceeding 10 cm in length were dissected to preserve native alignment and subjected to mild detergent-based decellularization, achieving efficient removal of cellular material while maintaining extracellular matrix structure and mechanics. The resulting scaffolds supported myogenic cell adhesion, proliferation, and differentiation, demonstrating their suitability for in vitro muscle tissue culture. This accessible approach provides a straightforward route to generate macroscale, structurally faithful skeletal muscle scaffolds, bridging the gap between whole-muscle and minced-tissue decellularization methods.

Severe burn injuries pose significant clinical challenges, with high risks of infection, excessive inflammation, and impaired wound healing. Mesenchymal stem cells (MSCs) have shown regenerative and antimicrobial potential; however, their therapeutic efficacy is constrained by poor survival and engraftment. Here, we demonstrate that priming MSCs with insulin-secreting cells (ISCs) and encapsulating them in hydrogels (HEMI) enhances their regenerative function, leading to accelerated healing of full-thickness burns in a porcine model. By 5 weeks, 80% of HEMI-treated wounds achieved complete closure, compared with 50% of MSC-only wounds and 0% of standard-of-care control wounds. All groups exhibited partial wound closure over time, but no control wounds reached complete closure within the study period. Histological analysis revealed complete epidermal and dermal regeneration with minimal fibrosis in HEMI-treated wounds. Single-cell RNA sequencing and differentially abundant sequencing analysis identified distinct MSC subpopulations whose relative abundance and transcriptional profiles differed between insulin-primed and control MSCs, with insulin priming promoting pathways involved in extracellular matrix stabilization, immune modulation, and oxidative stress resistance. Our findings suggest that insulin priming enhances MSC-mediated tissue repair via paracrine mechanisms, providing a clinically translatable strategy for improving burn treatment and regenerative medicine applications.

To develop bone grafts with superior osteoconductivity, we have fabricated unidirectionally connected porous carbonate apatite (CAp) via gelatin gelation combined with freeze-drying. A composite of calcium carbonate (CaCO3) and gelatin was first gelled at low temperature and then subjected to directional freeze-drying to create well-aligned macroporous channels. The samples were then sintered to remove the organic components and subsequently phosphatized to convert the composition into CAp. The resulting material exhibited a porosity exceeding 80% with fully interconnected unidirectional pores favorable for cell migration and vascular infiltration. Bone regeneration was evaluated by implanting the material into rabbit femoral bone defects; a comparison was also made with nonoriented porous controls. Histological and radiographical analyses demonstrated that the unidirectional porous structure significantly enhanced directional ingrowth of new bone tissue and accelerated early-stage bone formation relative to the control. This study demonstrates that unidirectional porous CAp fabricated via a gelatin-based freeze-casting method is promising for bone regeneration, particularly in clinical applications requiring guided bone formation.

Chronic tympanic membrane (TM) perforation remains difficult to resolve without surgery because of poor intrinsic healing capacity and limitations of passive, nonsurgical materials. Although patch-based approaches are common, most merely provide passive coverage and lack intrinsic therapeutic capability to drive tissue regeneration. We developed and clinically evaluated an extracellular matrix (ECM)-mimetic, drug-free nanopattern guidance (NG) patch for TM repair, marking a paradigm shift from passive coverage to active, biophysically driven regeneration. The NG patch is a biocompatible, implantable scaffold with aligned nanotopography that recapitulates native ECM architecture, coupled with a hydrocolloid adhesive layer to ensure secure placement. In a prospective study of 18 patients, the NG patch achieved a 61% overall healing rate with 50% complete closure and no serious adverse events. In rat models, a single application induced complete healing within 2 weeks. Mechanistic in vitro assays demonstrated that the nanopatterned surface enhances fibroblast adhesion, alignment, and directional migration, supporting organized tissue closure. Collectively, the NG patch offers a minimally invasive approach that activates TM repair through physical cues without exogenous drugs. This first clinical evaluation of an ECM-mimetic nanotopographical scaffold introduces a strategy to redefine the standard of care for chronic TM perforation and related defects.

Diabetes mellitus is a global public health problem, and impaired wound healing is a complication that significantly reduces patients' quality of life. Dysregulation of mitochondrial homeostasis is a key pathological feature contributing to impaired wound healing in diabetes. This dysregulation increases oxidative stress, resulting in impaired energy metabolism, endothelial dysfunction, and prolonged inflammatory responses. Photobiomodulation (PBM) is a noninvasive therapy that has been successfully used to promote diabetic wound healing by modulating mitochondrial homeostasis via multiple mechanisms. In this review, we have systematically summarized the following roles of PBM in restoring mitochondrial homeostasis to accelerate diabetic wound healing: improving mitochondrial dysfunction and oxidative stress through cytochrome C oxidase in the electron transport chain, thereby enhancing oxidative phosphorylation and adenosine triphosphate production; modifying mitochondrial dynamics by inhibiting the expression of dynamin-related protein 1 and promoting mitofusin-2 expression to restore mitochondrial morphology and function; reducing inflammation and promoting macrophage polarization from the M1 to M2 phenotype; activating signaling pathways (e.g., VEGF, PI3K/AKT/mTOR/GSK3-β, AMPK, RAS/MAPK, JAK/STAT, NF-κB, TGF-β/Smad) to enhance cell proliferation and angiogenesis and resolve inflammation. Beyond monotherapy, this review synthesizes the burgeoning field of PBM in combination with advanced therapeutic strategies, such as hydrogels, nanomaterials, small-molecule drugs, adipose-derived stem cells, and extracellular vesicles, highlighting their synergistic potential for enhanced efficacy. Finally, this review critically addresses the prevailing challenges in clinical translation, particularly the lack of standardized treatment parameters, and proposes future research directions. This comprehensive overview aims to solidify the scientific foundation of PBM and inspire the design of integrated, precision therapeutic strategies for diabetic wound management.

Anaplastic thyroid carcinoma (ATC) is a highly aggressive and treatment-resistant form of thyroid cancer, characterized by poor prognosis, rapid metastasis, and resistance to conventional therapies. Current treatment options, including surgery, chemotherapy, and radiation, are often ineffective in controlling the disease, underscoring the urgent need for novel therapeutic approaches. Nanotechnology has emerged as a promising strategy to overcome these challenges, offering innovative solutions for targeted drug delivery and noninvasive therapeutic modalities. This review explores the latest advancements in nanotechnology-driven strategies for treating ATC, with a particular focus on noninvasive therapies such as sonodynamic therapy and nano-pulse stimulation, as well as the development of nanomaterial-based drug delivery systems. These systems, including RNA-based nanocarriers, radionuclide-labeled nanoparticles, and nanoclay-based delivery systems, provide enhanced specificity and efficacy, overcoming the limitations of traditional treatments. Additionally, dual-modality theranostic systems, which combine diagnostic imaging and therapeutic payloads, hold great promise in improving early detection and real-time treatment monitoring. Despite the promising preclinical results, challenges such as tumor heterogeneity, drug resistance, and biocompatibility of nanomaterials remain in the clinical use. This review provides a comprehensive overview of the potential of nanotechnology to revolutionize the treatment of ATC, offering new hope for patients with this highly aggressive malignancy.

Three-dimensional (3D) printing technology, or additive manufacturing, has fundamentally transformed medical paradigms by shifting dentistry from traditional subtractive manufacturing to an era of personalized, biological regeneration. This review provides a comprehensive overview of the primary 3D printing classifications currently utilized, including stereolithography, fused deposition modeling, selective laser sintering, and material jetting, analyzing their specific technical principles and material capabilities. We systematically categorize their applications across diverse dental disciplines, ranging from endodontics, periodontal disease management, and prosthodontics to orthodontics, maxillofacial reconstruction, and temporomandibular joint regeneration. Beyond the fabrication of anatomical models and surgical guides, this article critically evaluates the efficacy of these technologies in constructing bioactive scaffolds and cell-laden hydrogels designed to induce osteogenesis and angiogenesis. Special emphasis is placed on the paradigm shift from passive mechanical restoration to active biological regeneration, highlighting the potential of bioprinting in restoring physiological vitality to native tissues. Despite current barriers regarding the trade-off between mechanical durability and biological activity, as well as vascularization challenges, the convergence of artificial intelligence and 4D printing promises to establish 3D printing as a foundational standard for the next generation of regenerative dental therapeutics.