Bioreactivity of decellularized animal, plant, and fungal scaffolds: perspectives for medical applications

Recent advances in plant-derived polysaccharide scaffolds in tissue engineering: A review

As a natural three-dimensional biopolymer, decellularized plant-derived scaffolds usually comprise various polysaccharides, mostly cellulose, pectin, and hemicellulose. They are characterized by natural biocompatibility and porous structures. The emergence of decellularized purified polysaccharide scaffolds provides an attractive method to overcome the challenges associated with nutrient delivery and biocompatibility, as they serve as optimal non-immune environments for stem cell adhesion and proliferation. To date, limited corresponding literature is available to systemically summarize the development and potential of these scaffolds in tissue engineering. Therefore, the current review summarized the biomimetic properties of plant-derived polysaccharide scaffolds and the latest progress in tissue engineering applications. This review first discusses the advantages of decellularized plant-derived polysaccharide scaffolds by briefly introducing their features and current limitations in clinical applications. Subsequently, the latest progress in emerging applications of regenerative biomaterials is reviewed, followed by a discussion of the studies on the interactions of biomaterials with cells and tissues. Finally, challenges in obtaining reliable scaffolds and possible future directions are discussed.

From Nature to Technology: Exploring the Potential of Plant-Based Materials and Modified Plants in Biomimetics, Bionics, and Green Innovations

This review explores the extensive applications of plants in areas of biomimetics and bioinspiration, highlighting their role in developing sustainable solutions across various fields such as medicine, materials science, and environmental technology. Plants not only serve essential ecological functions but also provide a rich source of inspiration for innovations in green nanotechnology, biomedicine, and architecture. In the past decade, the focus has shifted towards utilizing plant-based and vegetal waste materials in creating eco-friendly and cost-effective materials with remarkable properties. These materials are employed in making advancements in drug delivery, environmental remediation, and the production of renewable energy. Specifically, the review discusses the use of (nano)bionic plants capable of detecting explosives and environmental contaminants, underscoring their potential in improving quality of life and even in lifesaving applications. The work also refers to the architectural inspirations drawn from the plant world to develop novel design concepts that are both functional and aesthetic. It elaborates on how engineered plants and vegetal waste have been transformed into value-added materials through innovative applications, especially highlighting their roles in wastewater treatment and as electronic components. Moreover, the integration of plants in the synthesis of biocompatible materials for medical applications such as tissue engineering scaffolds and artificial muscles demonstrates their versatility and capacity to replace more traditional synthetic materials, aligning with global sustainability goals. This paper provides a comprehensive overview of the current and potential uses of living plants in technological advancements, advocating for a deeper exploration of vegetal materials to address pressing environmental and technological challenges.

Analyzing Mushroom Structural Patterns of a Highly Compressible and Expandable Hemostatic Foam for Gastric Perforation Repair

Nature presents the most beautiful patterns through evolving. Here, a layered porous pattern in golden ratio (0.618) is reported from a type of mushroom -Dictyophora Rubrovalvata stipe (DRS). The hierarchical structure shows a mathematical correlation with the golden ratio. This unique structure leads to superior mechanical properties. The gradient porous structure from outside to innermost endows it with asymmetrical hydrophilicity. A mathematical model is then developed to predict and apply to 3D printed structures. The mushroom is then explored to repair gastric perforation because the stomach is a continuous peristaltic organ, and the perforated site is subject to repeated mechanical movements and pressure changes. At present, endoscopic clipping is ineffective in treating ulcerative perforation with fragile surrounding tissues. Although endoscopic implant occlusion provides a new direction for the treatment of gastric ulcers, but the metal or plastic occluder needs to be removed, requiring a second intervention. Decellularized DRS (DDRS) is found with asymmetric water absorption rate, super-compressive elasticity, shape memory, and biocompatibility, making it a suitable occluder for the gastric perforation. The efficacy in blocking gastric perforation and promoting healing is confirmed by endoscopic observation and tissue analysis during a 2-month study.

An agarose-based TOCN-ECM bilayer lyophilized-hydrogel with hemostatic and regenerative properties for post-operative adhesion management

This study used a unique approach by developing a bilayer system that can simultaneously accomplish non-adhesion, hemostatic, and tissue regenerative properties. In this system, agarose was used as a carrier material, with an agarose-TEMPO-oxidized cellulose nanofiber (TOCN), (AT) layer acting as a non-adhesion layer and an Agarose-Extracellular matrix, (AE) layer acting as a tissue regenerative layer. Thrombin was loaded on the AE layer as an initiator of the healing process, by hemostasis. AT 1:4 showed 79.3 % and AE 1:4 showed 84.66 % cell viability initially confirming the biocompatible nature of the layers. The AE layer showed cell attachment and proliferation on its surface whereas on the AT layer, cells are visible but no attachment was observed. Furthermore, in vivo analysis was conducted. The non-adhesive layer was grafted between the cecum and peritoneal wall which showed that (AT 1:4) displayed remarkable non-adhesion properties as compared to a commercial product and the non-treated group. Hemostasis and tissue regeneration ability were evaluated using rat liver models. The bleeding time of AE 1:4TH was recorded as 160 s and the blood loss was 5.6 g. The results showed that (AE 1:4) displayed effective regeneration ability in the liver model after two weeks.

Copper ion/gallic acid MOFs-laden adhesive pomelo peel sponge effectively treats biofilm-infected skin wounds and improves healing quality

Bacterial infection and scar formation remain primary challenges in wound healing. To address these issues, we developed a decellularized pomelo peel (DPP) functionalized with an adhesive PVA-TSPBA hydrogel and antibacterial gallic acid/copper MOFs. The hybrid wound dressing demonstrates favorable biocompatibility. It does not impede the proliferation of fibroblasts or immune cells and can stimulate fibroblast migration, endothelial angiogenesis, and M2 macrophage polarization. Additionally, the dressing can scavenge reactive oxygen species (ROS) and provide antioxidant effects. Furthermore, DPP + MOF@Gel effectively inhibits the viability of S. aureus and E. coli in vitro and in vivo. The histological observations revealed enhanced granulation tissue formation, re-epithelialization, and angiogenesis in the DPP + MOF@Gel group compared to other groups. The local immune response also shifted from a pro-inflammatory to a pro-regenerative status with DPP + MOF@Gel treatment. The skin incision stitching experiment further exhibits DPP + MOF@Gel could reduce scar formation during wound healing. Taken together, the hybrid DPP + MOF@Gel holds great promise for treating bacteria-infected skin wounds and inhibiting scar formation during wound healing.

In vitro modeling of hepatocellular carcinoma niche on decellularized tomato thorny leaves: a novel natural three-dimensional (3D) scaffold for liver cancer therapeutics

Liver cancer is now one of the main causes leading to death worldwide. To achieve reliable therapeutic effects, it is crucial to develop efficient approaches to test novel anticancer drugs. Considering the significant contribution of tumor microenvironment to cell's response to medications, in vitro 3D bioinspiration of cancer cell niches can be regarded as an advanced strategy to improve the accuracy and reliability of the drug-based treatment. In this regard, decellularized plant tissues can perform as suitable 3D scaffolds for mammalian cell culture to create a near-to-real condition to test drug efficacy. Here, we developed a novel 3D natural scaffold made from decellularized tomato hairy leaves (hereafter called as DTL) to mimic the microenvironment of human hepatocellular carcinoma (HCC) for pharmaceutical purposes. The surface hydrophilicity, mechanical properties, and topography measurement and molecular analyses revealed that the 3D DTL scaffold is an ideal candidate for liver cancer modeling. The cells exhibited a higher growth and proliferation rate within the DTL scaffold, as verified by quantifying the expression of related genes, DAPI staining, and SEM imaging of the cells. Moreover, prilocaine, an anticancer drug, showed a higher effectiveness against the cancer cells cultured on the 3D DTL scaffold, compared to a 2D platform. Taken together, this new cellulosic 3D scaffold can be confidently proposed for chemotherapeutic testing of drugs on hepatocellular carcinoma.

Molecular dynamics simulations and in vitro studies of hybrid decellularized leaf-peptide-polypyrrole composites for potential tissue engineering applications

Tissue engineering (TE) aims to repair and regenerate damaged tissue by an assimilation of optimal combination of cells specific to the tissue with an appropriate biomaterial. In this work, a new biomaterial for potential cardiac TE applications was developed by utilizing a combination of in silico studies and in vitro experiments. Molecular dynamics (MD) simulations for the formation of the novel composite prepared from the decellularized leaf components cellulose and pectin along with the VEGF derived peptide (NYLTHRQ) and polypyrrole (PPy) was carried out to assess self-assembly, mechanical properties, and interactions with integrin and NPR-C receptors which are commonly found in cells of cardiac tissue. Results of molecular dynamics simulations indicated the successful formation of stable assemblies. MD simulations also revealed that the scaffold successfully interacted with integrin and NPR-C receptors. As a proof of concept, beet leaves were decellularized (DC) and cross-linked with NYLTHRQ and PPy using layer-by-layer assembly. Decellularization (DC) was confirmed by DNA and protein quantification. Incorporation of the NYLTHRQ peptide and polypyrrole was confirmed by FTIR spectroscopy and SEM imaging. The DC-NYLTHRQ-PPy scaffold was seeded with co-cultured cardiomyocytes and vascular smooth muscle cells. The scaffold promoted cell proliferation and adhesion. Actin and Troponin T immunofluorescence staining showed the presence of these critical cardiomyocyte markers. Thus, for the first time we have developed a decellularized leaf-peptide-PPy composite scaffold by a combination of in silico studies and laboratory analyses that may have potential applications in cardiac TE.Communicated by Ramaswamy H. Sarma.

Immunogenicity assessment of swim bladder-derived biomaterials

Fish swim bladder-derived biomaterials are prospective cardiovascular materials due to anti-calcification, adequate mechanical properties, and good biocompatibility. However, their immunogenic safety profile, which primarily determines their feasibility as medical devices in clinical practice, remains unknown. Herein, the immunogenicity of glutaraldehyde crosslinked fish swim bladder (Bladder-GA) and un-crosslinked swim bladder (Bladder-UN) samples was examined using in vitro and in vivo assays according to ISO 10993-20. The in vitro splenocyte proliferation assay showed that cell growth was lower in the extract medium of Bladder-UN and Bladder-GA, compared to the LPS-or Con A-treated group. Similar results were obtained in in vivo assays. In the subcutaneous implantation model, the thymus coefficient, spleen coefficient and ratio of immune cell subtypes showed no significant difference between the bladder groups and the sham group. In terms of the humoral immune response, the total IgM concentration was lower in the Bladder-GA and Bladder-UN groups (988 ± 238 μg ml^-1 and 1095 ± 296 μg ml^-1, respectively) than that in the sham group (1329 ± 132 μg ml^-1) at 7 days. The total IgG concentrations were 422 ± 78 μg ml^-1 in Bladder-GA and 469 ± 172 μg ml^-1 in Bladder-UN at 30 days, which were slightly higher than that in the sham group (276 ± 95 μg ml^-1) but there was no significant difference compared with Bovine-GA (468 ± 172 μg ml^-1), indicating that these materials did not elicit a strong humoral immune response. Systemic immune response-related cytokines and C-reactive protein were stable during implantation, while IL-4 levels increased with time. The classical foreign body response was not observed around all the implants, and the ratio of CD163+/iNOS macrophages in Bladder-GA and Bladder-UN was higher than that in the Bovine-GA group at the implanted site at 7 and 30 days. Finally, no organ toxicity was observed in any of the groups. Collectively, the swim bladder-derived material did not elicit significant aberrant immune responses in vivo, giving strong confidence for its application in tissue engineering or medical devices. Furthermore, more dedicated research on immunogenic safety assessment in large animal models is encouraged to facilitate the clinical practice of swim bladder-derived materials.

Engineered nanovesicles from stromal vascular fraction promote angiogenesis and adipogenesis inside decellularized adipose tissue through encapsulating growth factors

Acellular matrix is a commonly used biomaterial in the field of biomedical engineering and revascularization is the key process to affect the effect of acellular matrix on tissue regeneration. The application of bioactive factors related to angiogenesis has been popular in the regulation of revascularization, but the immune system clearance, uncontrollable systemic reactions, and other factors make this method face challenges. Recent reports showed that engineered cells into nanovesicles can reorganize cell membranes and encapsulate cellular active factors, extending the in vitro preservation of cytokines. However, the problems of exogenous biological contamination and tumorigenicity restricted the clinical transformation and wide application of this method. Here, we for the first time engineer stromal vascular fraction (SVF) which is extracted from fat into nanovesicles (SVF-EVs) for angiogenesis in the acellular matrix. SVF-EVs not only promote the migration of vascular endothelial cells in vitro, but also facilitate the lipogenic differentiation of mesenchymal stem cells. In vivo, SVF-EVs enhanced the retention of decellularized adipose tissue after transplanting to the subcutaneous area of nude mice. Immunofluorescence staining further showed that SVF-EVs promoted the formation of vascular networks with large lumen diameter in the grafted acellular matrix, accompanied by adipocyte regeneration peripherally. These findings reveal that SVF-EVs can be a viable method for accelerating revascularization in acellular matrix, and this process of squeezing tissue into nanovesicles shows the potential for rapid clinical transformation.

Bioprocessing by Decellularized Scaffold Biomaterials in Cultured Meat: A Review

As novel carrier biomaterials, decellularized scaffolds have promising potential in the development of cellular agriculture and edible cell-cultured meat applications. Decellularized scaffold biomaterials have characteristics of high biocompatibility, bio-degradation, biological safety and various bioactivities, which could potentially compensate for the shortcomings of synthetic bio-scaffold materials. They can provide suitable microstructure and mechanical support for cell adhesion, differentiation and proliferation. To our best knowledge, the preparation and application of plant and animal decellularized scaffolds have not been summarized. Herein, a comprehensive presentation of the principles, preparation methods and application progress of animal-derived and plant-derived decellularized scaffolds has been reported in detail. Additionally, their application in the culture of skeletal muscle, fat and connective tissue, which constitute the main components of edible cultured meat, have also been generally discussed. We also illustrate the potential applications and prospects of decellularized scaffold materials in future foods. This review of cultured meat and decellularized scaffold biomaterials provides new insight and great potential research prospects in food application and cellular agriculture.

Effect of naturally derived surgical hemostatic materials on the proliferation of A549 human lung adenocarcinoma cells

Hemostatic materials are generally applied in surgical operations for cancer, but their effects on the growth and recurrence of tumors are unclear. Herein, three commonly used naturally derived hemostatic materials, gelatin sponge, Surgicel (oxidized regenerated cellulose), and biopaper (mixture of sodium hyaluronate and carboxymethyl chitosan), were cocultured with A549 human lung adenocarcinoma cells in vitro. Furthermore, the performance of hemostatic materials and the tumorigenicity of the materials with A549 ​cells were observed after subcutaneous implantation into BALB/c mice. The in vitro results showed that biopaper was dissolved quickly, with the highest cell numbers at 2 and 4 days of culture. Gelatin sponges retained their structure and elicited the least cell infiltration during the 2- to 10-day culture. Surgicel partially dissolved and supported cell growth over time. The in vivo results showed that biopaper degraded rapidly and elicited an acute Th1 lymphocyte reaction at 3 days after implantation, which was decreased at 7 days after implantation. The gelatin sponge resisted degradation and evoked a hybrid M1/M2 macrophage reaction at 7–21 days after implantation, and a protumor M2d subset was confirmed. Surgicel resisted early degradation and caused obvious antitumor M2a macrophage reactions. Mice subjected to subcutaneous implantation of A549 ​cells and hemostatic materials in the gelatin sponge group had the largest tumor volumes and the shortest overall survival (OS), while the Surgicel and the biopaper group had the smallest volumes and the longest OS. Therefore, although gelatin sponges exhibited cytotoxicity to A549 ​cells in vitro, they promoted the growth of A549 ​cells in vivo, which was related to chronic M2d macrophage reaction. Surgicel and biopaper inhibited A549 ​cell growth in vivo, which is associated with chronic M2a macrophage reaction or acute Th1 lymphocyte reaction.

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The gelatin sponge, Surgicel and biopaper had different effects on A549 ​cell growth and proliferation.

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Biopaper degraded rapidly in vivo and elicited an antitumor Th1 lymphocyte reaction at acute inflammatory phase.

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The gelatin sponge resisted degradation and evoked a protumor M2d macrophage reactions.

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Surgicel resisted early degradation and caused obvious antitumor M2a macrophage reactions.

Natural Biomaterials from Biodiversity for Healthcare Applications

Natural biomaterials originating during the growth cycles of all living organisms have been used for many applications. They span from bioinert to bioactive materials including bioinspired ones. As they exhibit an increasing degree of sophistication, natural biomaterials have proven suitable to address the needs of the healthcare sector. Here the different natural healthcare biomaterials, their biodiversity sources, properties, and promising healthcare applications are reviewed. The variability of their properties as a result of considered species and their habitat is also discussed. Finally, some limitations of natural biomaterials are discussed and possible future developments are provided as more natural biomaterials are yet to be discovered and studied.

Titanate nanoribbon-based nanobiohybrid for potential applications in regenerative medicine

Nanoparticles capable of mimicking natural tissues represent a major technological advancement in regenerative medicine. In this pilot study, the development of a new nanohybrid composed of titanate nanoribbons to mimic the extracellular matrix is reported. During the first phase, nanoribbons were synthesized by hydrothermal treatment. Subsequently, titanate nanoribbons were functionalized by heterobifunctional polyethylene-glycol (PEG) to graft type I collagen on their surface. Biological properties of this new nanobiohybrid such as cytotoxicity to cardiac cells and platelet aggregation ability were evaluated. The so-formed nanobiohybrid permits cellular adhesion and proliferation favoring fine cardiac tissue healing and regeneration.

Titanate nanoribbons functionalized by heterobifunctional polymer and type I collagen for cellular adhesion and proliferation. This new nanobiohybrid affected neither cytotoxicity nor platelet aggregation ability.

Bioinspired In Vitro Brain Vasculature Model for Nanomedicine Testing Based on Decellularized Spinach Leaves

Animal testing is often criticized due to ethical issues and complicated translation of the results obtained to the clinical stage of drug development. Existing alternative models for nanopharmaceutical testing still have many limitations and do not significantly decrease the number of animals used. We propose a simple, bioinspired in vitro model for nanopharmaceutical drug testing based on the decellularized spinach leaf's vasculature. This system is similar to human arterioles and capillaries in terms of diameter (300-10 μm) and branching. The model has proven its suitability to access the maneuverability of magnetic nanoparticles, particularly those composed of Fe₃O₄. Moreover, the thrombosis has been recreated in the model's vasculature. We have tested and compared the effects of both a single-chain urokinase plasminogen activator (scuPA) and a magnetically controlled nanocomposite prepared by heparin-mediated cross-linking of scuPA with Fe₃O₄ nanoparticles. Compositions were tested both in static and flow conditions.