Apple derived cellulose scaffolds for 3D mammalian cell culture

Decellularized apple hypanthium as a plant-based biomaterial for cartilage regeneration in vitro: a comparative study of progenitor cell types and environmental conditions

BACKGROUND

Decellularized plant tissues have been shown to enhance the integration and proliferation of human cells, demonstrating biocompatibility. These tissues are now being considered as valuable biomaterials for tissue engineering due to their diverse architectures and favorable cytocompatibility. In this study, we assessed decellularized apple hypanthium as a potential biomaterial for generating cartilage-like structures, utilizing four different progenitor cell types and varying environmental conditions in vitro.

RESULTS

Cell viability assays indicated integration and cell proliferation. Histological staining and gene expression analyses confirmed the synthesis and deposition of a cartilaginous extracellular matrix. Notably, hypoxia had varying effects on chondrogenesis based on the cell type. Among the progenitor cells evaluated, those derived from auricular perichondrium were particularly promising, as they differentiated into chondrocytes without requiring a low-oxygen environment. Additionally, our findings demonstrated that apple-derived biomaterials outperformed microencapsulation in alginate beads in promoting chondrogenesis.

CONCLUSION

These results highlight the potential of plant-based biomaterials for the development of implantable devices for cartilage regeneration and suggest broader applications in tissue engineering and future clinical endeavors.

Understanding nonwoody cellulose extractions, treatments, and properties for biomedical applications

Cellulose is a β1-4 glucan polymer that constitutes the most abundant polysaccharide on Earth. Recent advancements in its production have provided greater control and enabled the creation of functional celluloses with enhanced physical, mechanical, and chemical properties. With the increasing interest in polysaccharide materials, attention is now focused on alternative sources, particularly those derived from nonwoody plants such as jute, sisal, cotton, flax, or hemp. Compared to wood, nonwoody plants generally possess lower lignin content, shorter growing cycles with moderate irrigation requirements, high annual crops, and substantial annual cellulose yield. The discovery of nonwoody cellulose disintegration opens new avenues for environmentally friendly approaches, naturally paving the way for the exploration of new applications for this versatile material. Despite the broad range of potential applications, cellulose has primarily been utilized for industrial purposes, with only limited interest in the biomedical sector in the early stages. Therefore, this review focuses on nonwoody cellulose extraction and pretreatments while evaluating the compositions and properties of nonwoody plants, resulting in distinctive features beneficial for biomedical applications. This review aims to facilitate a deeper understanding of nonwoody cellulose and its prospects for biomedical applications.

Cultivation of bovine lipid chunks on Aloe vera scaffolds

Aloe vera, renowned for its medicinal and food applications, offers a sustainable, scalable, and cost-effective scaffold material for cultured meat production. Our method repurposes Aloe vera parenchyma into a sustainable and innovative scaffold for CM production. These scaffolds, derived from agricultural byproducts, feature a porous structure that retains liquids and supports bovine mesenchymal stem cell (bMSC) adhesion, proliferation, and extracellular matrix formation. By incorporating oleic acid, the scaffolds enable the accumulation of fat-like tissue, creating "lipid chunks" that can enhance the texture and flavor profile of plant-based meat alternatives. Furthermore, scalability is addressed by culturing the scaffolds in a macrofluidic single-use bioreactor (MSUB), showcasing the potential for large-scale production. This work demonstrates Aloe vera scaffold's versatility as a cost-effective material and highlights its promise for sustainable protein solutions and tissue engineering applications.

Growing meat on autoclaved vegetables with biomimetic stiffness and micro-patterns

Cultured meat needs edible bio-scaffolds that provide not only a growth milieu for muscle and adipose cells, but also biomimetic stiffness and tissue-sculpting topography. Current meat-engineering technologies struggle to achieve scalable cell production, efficient cell differentiation, and tissue maturation in one single culture system. Here we propose an autoclaving strategy to transform common vegetables into muscle- and adipose-engineering scaffolds, without undergoing conventional plant decellularization. We selected vegetables with natural anisotropic and isotropic topology mimicking muscle and adipose microstructures respectively. We further adjusted vegetable stiffness by autoclaving, to emulate the mechanical properties of animal tissues. Autoclaved vegetables preserve rich cell-affinitive moieties, yielding a good cell culture effect with simplified processing. Autoclaved Chinese chive and Shiitake mushroom with anisotropic micro-patterns support the scalable expansion of muscle cells, improved cell alignment and myogenesis. Autoclaved isotropic loofah encourages adipocyte proliferation and lipid accumulation. Our engineered muscle- and fat-on-vegetables can further construct meat stuffing or layered meat chips. Autoclaved vegetables possess tissue-mimicking stiffness and topology, and bring biochemical benefits, operational ease, cost reduction and bioreactor compatibility. Without needing decellularization, these natural biomaterials may see scale-up applications in meat analog bio-fabrication.

Decellularized Green and Brown Macroalgae as Cellulose Matrices for Tissue Engineering

Scaffolds resembling the extracellular matrix (ECM) provide structural support for cells in the engineering of tissue constructs. Various material sources and fabrication techniques have been employed in scaffold production. Cellulose-based matrices are of interest due to their abundant supply, hydrophilicity, mechanical strength, and biological inertness. Terrestrial and marine plants offer diverse morphologies that can replicate the ECM of various tissues and be isolated through decellularization protocols. In this study, three marine macroalgae species-namely Durvillaea poha, Ulva lactuca, and Ecklonia radiata-were selected for their morphological variation. Low-intensity, chemical treatments were developed for each species to maintain native cellulose structures within the matrices while facilitating the clearance of DNA and pigment. Scaffolds generated from each seaweed species were non-toxic for human dermal fibroblasts but only the fibrous inner layer of those derived from E. radiata supported cell attachment and maturation over the seven days of culture. These findings demonstrate the potential of E. radiata-derived cellulose scaffolds for skin tissue engineering and highlight the influence of macroalgae ECM structures on decellularization efficiency, cellulose matrix properties, and scaffold utility.

Hijacking plant skeletons for biomedical applications: from regenerative medicine and drug delivery to biosensing

The field of biomedical engineering continually seeks innovative technologies to address complex healthcare challenges, ranging from tissue regeneration to drug delivery and biosensing. Plant skeletons offer promising opportunities for these applications due to their unique hierarchical structures, desirable porosity, inherent biocompatibility, and adjustable mechanical properties. This review comprehensively discusses chemical principles underlying the utilization of plant-based scaffolds in biomedical engineering. Highlighting their structural integrity, tunable properties, and possibility of chemical modification, the review explores diverse preparation strategies to tailor plant skeleton properties for bone, neural, cardiovascular, skeletal muscle, and tendon tissue engineering. Such applications stem from the cellulosic three-dimensional structure of different parts of plants, which can mimic the complexity of native tissues and extracellular matrices, providing an ideal environment for cell adhesion, proliferation, and differentiation. We also discuss the application of plant skeletons as carriers for drug delivery due to their structural diversity and versatility in encapsulating and releasing therapeutic agents with controlled kinetics. Furthermore, we present the emerging role played by plant-derived materials in biosensor development for diagnostic and monitoring purposes. Challenges and future directions in the field are also discussed, offering insights into the opportunities for future translation of sustainable plant-based technologies to address critical healthcare needs.

Decellularized Macroalgae as Complex Hydrophilic Structures for Skin Tissue Engineering and Drug Delivery

Due to their indisputable biocompatibility and abundant source, biopolymers are widely used to prepare hydrogels for skin tissue engineering. Among them, cellulose is a great option for this challenging application due to its increased water retention capacity, mechanical strength, versatility and unlimited availability. Since algae are an unexploited source of cellulose, the novelty of this study is the decellularization of two different species, freshly collected from the Black Sea coast, using two different chemical surfactants (sodium dodecyl sulphate and Triton X-100), and characterisation of the resulted complex biopolymeric 3D matrices. The algae nature and decellularization agent significantly influenced the matrices porosity, while the values obtained for the hydration degree included them in hydrogel class. Moreover, their capacity to retain and then controllably release an anti-inflammatory drug, ibuprofen, led us to recommend the obtained structures as drug delivery systems. The decellularized macroalgae hydrogels are bioadhesive and cytocompatible in direct contact with human keratinocytes and represent a great support for cells. Finally, it was noticed that human keratinocytes (HaCaT cell line) adhered and populated the structures during a monitoring period of 14 days.

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.

The important role of cellular mechanical microenvironment in engineering structured cultivated meat: Recent advances

Cultivated meat (CM) provides a potential solution to meet the rising demand for eco-friendly meat supply systems. Recent efforts focus on producing CM that replicates the architecture and textural toughness of natural skeletal muscle. Significance of the regulated role of cellular microenvironment in myogenesis has been reinforced by the substantial influence of mechanical cues in mediating the muscle tissue organization. However, the formation of structured CM has not been adequately described in context of the mechanical microenvironment. In this review, we provide an updated understanding of the myogenesis process within mechanically dynamic three-dimensional microenvironments, discuss the effects of environmental mechanical factors on muscle tissue regeneration and how cell mechanics respond to the mechanical condition, and further highlight the role of mechanical cues as important references in constructing a sustainable Hydrocolloids-based biomaterials for CM engineering. These findings help to overcome current limitations in improving the textural properties of CM.

Cellulose as a sustainable scaffold material in cultivated meat production

The rapid progress in cultivated meat research has engendered considerable attention towards the edible scaffolding biomaterials employed in the production. Cellulose has the advantages in availability, edibility, animal-free origin, etc., which show its potential in wide fields. This review begins by presenting the fundamental physical and chemical properties of cellulose from different sources, including plant and bacterial cellulose. Subsequently, we summarize the application of cellulose especially in cultivated meat and tissue engineering. Furthermore, we explore various methods for preparing cellulose-based scaffolds for cultivated meat, encompassing five specific structural variations. In the end, associated with utilizing cellulose in cultivated meat production, we address several primary challenges surrounding to cell adhesion, scaling up, processibility and mechanical properties, and provide potential innovations. This review underscores the potential of cellulose as a versatile biomaterial in the cultivated meat industry and provides insight into addressing critical challenges for its integration.

Three-dimensional pore structure of the decellularized parsley scaffold regulates myogenic differentiation for cell cultured meat

Decellularized plant scaffolds have been used to develop edible scaffolds for cell cultured meat because of their natural structures similar to that of mammalian tissues. However, their diverse three-dimensional (3D) porous structures may lead to differences in myogenic differentiation of skeletal muscle cells. In this study, parsley plant tissues were decellularized and modified by type A gelatin and transglutaminase while retaining, respectively, longitudinal fibrous and transverse honeycomb pore structures. The effects of the structure of the decellularized parsley scaffold on the proliferation and myogenic differentiation of C2C12 cells were investigated and the quality of cell cultured meat was evaluated. The results showed that fibrous pore structure guided cells to be arranged in parallel, whereas honeycomb pore structure connected cells in a circular pattern. After induced differentiation, the fibrous scaffolds were more inclined to form multinucleated myotubes with higher expression of myogenic genes and proteins, and the final cell-based meat contained higher total protein content. Decellularized plant scaffolds with fibrous pore structure were more suitable for myogenic differentiation of C2C12 cells, providing support to the development of edible scaffolds for cultured meat. PRACTICAL APPLICATION: This study investigated the different three-dimensional (3D) pore structure of parsley parenchyma to gain insight into how the 3D pore structure of decellularized plant scaffolds regulates myogenic differentiation, which is expected to address the unstable myogenic differentiation of skeletal muscle cells on decellularized plant scaffolds in cell culture meat production.

Bioinks for bioprinting using plant-derived biomaterials

Three-dimensional (3D) bioprinting has revolutionized tissue engineering by enabling the fabrication of complex and functional human tissues and organs. An essential component of successful 3D bioprinting is the selection of an appropriate bioink capable of supporting cell proliferation and viability. Plant-derived biomaterials, because of their abundance, biocompatibility, and tunable properties, hold promise as bioink sources, thus offering advantages over animal-derived biomaterials, which carry immunogenic concerns. This comprehensive review explores and analyzes the potential of plant-derived biomaterials as bioinks for 3D bioprinting of human tissues. Modification and optimization of these materials to enhance printability and biological functionality are discussed. Furthermore, cancer research and drug testing applications of the use of plant-based biomaterials in bioprinting various human tissues such as bone, cartilage, skin, and vascular tissues are described. Challenges and limitations, including mechanical integrity, cell viability, resolution, and regulatory concerns, along with potential strategies to overcome them, are discussed. Additionally, this review provides insights into the potential use of plant-based decellularized ECM (dECM) as bioinks, future prospects, and emerging trends in the use of plant-derived biomaterials for 3D bioprinting applications. The potential of plant-derived biomaterials as bioinks for 3D bioprinting of human tissues is highlighted herein. However, further research is necessary to optimize their processing, standardize their properties, and evaluate their long-termin vivoperformance. Continued advancements in plant-derived biomaterials have the potential to revolutionize tissue engineering and facilitate the development of functional and regenerative therapies for diverse clinical applications.

Methods to Screen the Adhesion of Fish Cells on Plant-, Algal- and Fungal-Derived Biomaterials

Cellular agriculture, an alternative and innovative approach to sustainable food production, has gained momentum in recent years. However, there is limited research into the production of cultivated seafood. Here, we investigated the ability of fish mackerel cells (Scomber scombrus) to adhere to plant, algal and fungal-based biomaterial scaffolds, aiming to optimize the cultivation of fish cells for use in cellular agriculture. A mackerel cell line was utilized, and metabolic assays and confocal imaging were utilized to track cell adhesion, growth, and differentiation on the different biomaterials. The mackerel cells adhered and grew on gelatin (positive control), zein, and soy proteins, as well as on alginate, chitosan, and cellulose polysaccharides. The highest adhesion and growth were on the zein and chitosan substrates, apart from the gelatin control. These findings provide a blueprint to enhance scaffold selection and design, contributing to the broader field of cellular agriculture through the development of scalable and eco-conscious solutions for meeting the growing global demand for seafood.

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.

Scalable Processes for Culturing Meat Using Edible Scaffolds

There is increasing consumer demand for alternative animal protein products that are delicious and sustainably produced to address concerns about the impacts of mass-produced meat on human and planetary health. Cultured meat has the potential to provide a source of nutritious dietary protein that both is palatable and has reduced environmental impact. However, strategies to support the production of cultured meats at the scale required for food consumption will be critical. In this review, we discuss the current challenges and opportunities of using edible scaffolds for scaling up the production of cultured meat. We provide an overview of different types of edible scaffolds, scaffold fabrication techniques, and common scaffold materials. Finally, we highlight potential advantages of using edible scaffolds to advance cultured meat production by accelerating cell growth and differentiation, providing structure to build complex 3D tissues, and enhancing the nutritional and sensory properties of cultured meat.

Decellularised plant scaffolds facilitate porcine skeletal muscle tissue engineering for cultivated meat biomanufacturing

Cultivated meat (CM) offers a sustainable and ethical alternative to conventional animal agriculture, involving cell maturation in a controlled environment. To emulate the structural complexity of traditional meat, the development of animal-free and edible scaffolds is crucial, providing vital physical and biological support during tissue development. The aligned vascular bundles of the decellularised asparagus scaffold were selected to facilitate the attachment and alignment of murine myoblasts (C2C12) and porcine adipose-derived mesenchymal stem cells (pADMSCs). Muscle differentiation was assessed through immunofluorescence staining with muscle markers, including Myosin heavy chain (MHC), Myogenin (MYOG), and Desmin. The metabolic activity of Creatine Kinase in C2C12 differentiated cells significantly increased compared to proliferated cells. Quantitative PCR analysis revealed a significant increase in Myosin Heavy Polypeptide 1 (MYH1) and MYOG expression compared to Day 0. These results highlight the application of decellularised plant scaffold (DPS) as a promising, edible material conducive to cell attachment, proliferation, and differentiation into muscle tissue. To create a CM prototype with biological mimicry, pADMSC-derived muscle and fat cells were also co-cultured on the same scaffold. The co-culture was confirmed through immunofluorescence staining of muscle markers and LipidTOX staining, revealing distinct muscle fibres and adipocytes containing lipid droplets respectively. Texture profile analysis conducted on uncooked CM prototypes and pork loin showed no significant differences in textural values. However, the pan-fried CM prototype differed significantly in hardness and chewiness compared to pork loin. Understanding the scaffolds' textural profile enhances our insight into the potential sensory attributes of CM products. DPS shows potential for advancing CM biomanufacturing.

Cultivation of Bovine Mesenchymal Stem Cells on Plant-Based Scaffolds in a Macrofluidic Single-Use Bioreactor for Cultured Meat

Reducing production costs, known as scaling, is a significant obstacle in the advancement of cultivated meat. The cultivation process hinges on several key components, e.g., cells, media, scaffolds, and bioreactors. This study demonstrates an innovative approach, departing from traditional stainless steel or glass bioreactors, by integrating food-grade plant-based scaffolds and thermoplastic film bioreactors. While thermoplastic films are commonly used for constructing fluidic systems, conventional welding methods are cost-prohibitive and lack rapid prototyping capabilities, thus inflating research and development expenses. The developed laser welding technique facilitates contamination-free and leakproof sealing of polyethylene films, enabling the efficient fabrication of macrofluidic systems with various designs and dimensions. By incorporating food-grade plant-based scaffolds, such as rice seeded with bovine mesenchymal stem cells, into these bioreactors, this study demonstrates sterile cell proliferation on scaffolds within macrofluidic systems. This approach not only reduces bioreactor prototyping and construction costs but also addresses the need for scalable solutions in both research and industrial settings. Integrating single-use bioreactors with minimal shear forces and incorporating macro carriers such as puffed rice may further enhance biomass production in a scaled-out model. The use of food-grade plant-based scaffolds aligns with sustainable practices in tissue engineering and cultured-meat production, emphasizing its suitability for diverse applications.

Plant Decellularization by Chemical and Physical Methods for Regenerative Medicine: A Review Article

Fabricating three-dimensional (3D) scaffolds is attractive due to various advantages for tissue engineering, such as cell migration, proliferation, and adhesion. Since cell growth depends on transmitting nutrients and cell residues, naturally vascularized scaffolds are superior for tissue engineering. Vascular passages help the inflow and outflow of liquids, nutrients, and waste disposal from the scaffold and cell growth. Porous scaffolds can be prepared by plant tissue decellularization which allows for the cultivation of various cell lines depending on the intended application. To this end, researchers decellularize plant tissues by specific chemical and physical methods. Researchers use plant parts depending on their needs, for example, decellularizing the leaves, stems, and fruits. Plant tissue scaffolds are advantageous for regenerative medicine, wound healing, and bioprinting. Studies have examined various plants such as vegetables and fruits such as orchid, parsley, spinach, celery, carrot, and apple using various materials and techniques such as sodium dodecyl sulfate, Triton X-100, peracetic acid, deoxyribonuclease, and ribonuclease with varying percentages, as well as mechanical and physical techniques like freeze-thaw cycles. The process of data selection, retrieval, and extraction in this review relied on scholarly journal publications and other relevant papers related to the subject of decellularization, with a specific emphasis on plant-based research. The obtained results indicate that, owing to the cellulosic structure and vascular nature of the decellularized plants and their favorable hydrophilic and biological properties, they have the potential to serve as biological materials and natural scaffolds for the development of 3D-printing inks and scaffolds for tissue engineering.

Application of pulsed electric field technology to skin engineering

Tissue engineering encompasses a range of techniques that direct the growth of cells into a living tissue construct for regenerative medicine applications, disease models, drug discovery, and safety testing. These techniques have been implemented to alleviate the clinical burdens of impaired healing of skin, bone, and other tissues. Construct development requires the integration of tissue-specific cells and/or an extracellular matrix-mimicking biomaterial for structural support. Production of such constructs is generally expensive and environmentally costly, thus eco-sustainable approaches should be explored. Pulsed electric field (PEF) technology is a nonthermal physical processing method commonly used in food production and biomedical applications. In this review, the key principles of PEF and the application of PEF technology for skin engineering will be discussed, with an emphasis on how PEF can be applied to skin cells to modify their behaviour, and to biomaterials to assist in their isolation or sterilisation, or to modify their physical properties. The findings indicate that the success of PEF in tissue engineering will be reliant on systematic evaluation of key parameters, such as electric field strength, and their impact on different skin cell and biomaterial types. Linking tangible input parameters to biological responses critical to healing will assist with the development of PEF as a sustainable tool for skin repair and other tissue engineering applications.

Development of tissue-engineered vascular grafts from decellularized parsley stems

Cardiovascular diseases are mostly associated with narrowing or blockage of blood vessels, and it is the most common cause of death worldwide. The use of vascular grafts is a promising approach to bypass or replace the blocked vessels for long-term treatment. Although autologous arteries or veins are the most preferred tissue sources for vascular bypass, the limited presence and poor quality of autologous vessels necessitate seeking alternative biomaterials. Recently, synthetic grafts have gained attention as an alternative to autologous grafts. However, the high failure rate of synthetic grafts has been reported primarily due to thrombosis, atherosclerosis, intimal hyperplasia, or infection. Thrombosis, the main reason for failure upon implantation, is associated with damage or absence of endothelial cell lining in the vascular graft's luminal surface. To overcome this, tissue-engineered vascular grafts (TEVGs) have come into prominence. Alongside the well-established scaffold manufacturing techniques, decellularized plant-based constructs have recently gained significant importance and are an emerging field in tissue engineering and regenerative medicine. Accordingly, in this study, we demonstrated the fabrication of tubular scaffolds from decellularized parsley stems and recellularized them with human endothelial cells to be used as a potential TEVG. Our results suggested that the native plant DNA was successfully removed, and soft tubular biomaterials were successfully manufactured via the chemical decellularization of the parsley stems. The decellularized parsley stems showed suitable mechanical and biological properties to be used as a TEVG material, and they provided a suitable environment for the culture of human endothelial cells to attach and create a pseudo endothelium prior to implantation. This study is the first one to demonstrate the potential of the parsley stems to be used as a potential TEVG biomaterial.

Derivation and Characterization of Novel Cytocompatible Decellularized Tissue Scaffold for Myoblast Growth and Differentiation

The selection of an appropriate scaffold is imperative for the successful development of alternative animal protein in the form of cultured meat or lab-grown meat. Decellularized tissues have been suggested as a potential scaffold for cultured meat production owing to their capacity to support an optimal environment and niche conducive to cell proliferation and growth. This approach facilitates the systematic development of 3D tissues in the laboratory. Decellularized scaffold biomaterials have characteristics of high biocompatibility, biodegradation, and various bioactivities, which could potentially address the limitations associated with synthetic bio-scaffold materials. The present study involved the derivation and characterization of a decellularized scaffold from mushroom tissue following subsequent assessment of the scaffold's capacity to support myogenic differentiation. Mushroom sections were soaked in nuclease and detergent solution for 4 days. Furthermore, decellularization was confirmed by histology and DAPI staining, which showed the removal of cellular components and nuclei. Myoblast cells were seeded onto decellularized tissue, which exhibited excellent cytocompatibility and promoted myogenic growth and differentiation. The study's findings can serve as a foreground for the generation of an edible and natural scaffold for producing a safe and disease-free source of alternative animal protein, potentially reducing the burden on the health sector caused by conventional animal protein production and consumption.

3D printed drug loaded nanomaterials for wound healing applications

Wounds are a stern healthcare concern in the growth of chronic disease conditions as they can increase healthcare costs and complicate internal and external health. Advancements in the current and newer management systems for wound healing should be in place to counter the health burden of wounds. Researchers discovered that two-dimensional (2D) media lacks appropriate real-life detection of cellular matter as these have highly complicated and diverse structures, compositions, and interactions. Hence, innovation towards three-dimensional (3D) media is called to conquer the high-level assessment and characterization in vivo using new technologies. The application of modern wound dressings prepared from a degenerated natural tissue, biodegradable biopolymer, synthetic polymer, or a composite of these materials in wound healing is currently an area of innovation in tissue regeneration medicine. Moreover, the integration of 3D printing and nanomaterial science is a promising approach with the potential for individualized, flexible, and precise technology for wound care approaches. This review encompasses the outcomes of various investigations on recent advances in 3D-printed drug-loaded natural, synthetic, and composite nanomaterials for wound healing. The challenges associated with their fabrication, clinical application progress, and future perspectives are also addressed.

A typical method for decellularization of plants as biomaterials

Decellularization is a process by which cells are removed from tissues or organs, leaving behind the extracellular matrix (ECM) structure. This process has gained interest in the fields of tissue engineering and regenerative medicine as a way to prepare suitable scaffolds for tissue reconstruction. Although the initial efforts come with the animal tissues, this technique can also be applied to various plant tissues with simple modifications, as plant-derived biomaterials have the benefit of being biocompatible and serving as a safe, all-natural substitute for synthetic or animal originated materials. Additionally, plant-derived biomaterials may help cells grow and differentiate, creating a three-dimensional environment for tissue regeneration and repair. Here we demonstrate a general method for plant tissue decellularization, including already experienced approaches and techniques.•Exhibit the basic steps for plant decellularization, which may be applied to several other plant tissues.•The proposed approach may be optimized considering various intended uses.•Gives basic information for the determination of decellularization efficiency.

Plant Cellulose as a Substrate for 3D Neural Stem Cell Culture

Neural stem cell (NSC)-based therapies are at the forefront of regenerative medicine strategies for various neural defects and injuries such as stroke, traumatic brain injury, and spinal cord injury. For several clinical applications, NSC therapies require biocompatible scaffolds to support cell survival and to direct differentiation. Here, we investigate decellularized plant tissue as a novel scaffold for three-dimensional (3D), in vitro culture of NSCs. Plant cellulose scaffolds were shown to support the attachment and proliferation of adult rat hippocampal neural stem cells (NSCs). Further, NSCs differentiated on the cellulose scaffold had significant increases in their expression of neuron-specific beta-III tubulin and glial fibrillary acidic protein compared to 2D culture on a polystyrene plate, indicating that the scaffold may enhance the differentiation of NSCs towards astrocytic and neuronal lineages. Our findings suggest that plant-derived cellulose scaffolds have the potential to be used in neural tissue engineering and can be harnessed to direct the differentiation of NSCs.

Aligned skeletal muscle assembly on a biofunctionalized plant leaf scaffold

Decellularized plant scaffolds have drawn attention as alternative tissue culture platforms due to their wide accessibility, biocompatibility, and diversity of innate microstructures. Particularly, in this work, monocot leaves with innate uniaxial micropatterned topography were utilized to promote cell alignment and elongation. The leaf scaffold was biofunctionalized with poly(PEGMEMA-r-VDM-r-GMA) copolymer that prevented non-specific protein adsorption and was modified with cell adhesive RGD peptide to enable cell adhesion and growth in serum-free media. The biofunctionalized leaf supported the adhesion, growth, and alignment of various human cells including embryonic stem cells (hESC) derived muscle cells. The hESC-derived myogenic progenitor cells cultured on the biofunctionalized leaf scaffold adopted a parallel orientation and were elongated along the leaf topography. These cells showed significant early myogenic differentiation and muscle-like bundled myotube formation. The aligned cells formed compact myotube assemblies and showed uniaxial muscle contraction under chemical stimulation, a critical requirement for developing functional skeletal muscle tissue. Polymer-functionalized plant leaf scaffolds offer a novel human cell culture platform and have potential in human tissue engineering applications that require parallel alignment of cells. STATEMENT OF SIGNIFICANCE: Plant scaffolds are plentiful sources in nature and present a prefabricated construct to present topographical cues to cells. Their feature width is ideal for human cell alignment and elongation, especially for muscle cells. However, plant scaffolds lack proteins that support mammalian cell culture. We have developed a polymer coated leaf scaffold that enables cell adhesion and growth in serum-free media. Human muscle cells cultured on the biofunctionalized leaf, aligned along the natural parallel micro-patterned leaf topography, and formed muscle-like bundled myotube assemblies. These assemblies showed uniaxial muscular contraction, a critical requirement for developing functional skeletal muscle tissue. The biodiversity of the plant materials offers a novel human cell culture platform with potential in human tissue engineering.

Biocompatible coatings based on photo-crosslinkable cellulose derivatives

Materials derived from renewable resources have great potential to replace fossil-based plastics in biomedical applications. In this study, the synthesis of cellulose-based photoresists by esterification with methacrylic acid anhydride and sorbic acid was investigated. These resists polymerize under UV irradiation in the range of λ = 254 nm to 365 nm, with or, in the case of the sorbic acid derivative, without using an additional photoinitiator. Usability for biomedical applications was demonstrated by investigating the adhesion and viability of a fibrosarcoma cell line (HT-1080). Compared to polystyrene, the material widely used for cell culture dishes, cell adhesion to the biomaterials tested was even stronger, as assessed by a centrifugation assay. Remarkably, chemical surface modifications of cellulose acetate with methacrylate and sorbic acid allow direct attachment of HT-1080 cells without adding protein modifiers or ligands. Furthermore, cells on both biomaterials show similar cell viability, not significantly different from polystyrene, indicating no significant impairment or enhancement, allowing the use of these cellulose derivatives as support structures for scaffolds or as a self-supporting coating for cell culture solely based on renewable resources.

Balance between the cell viability and death in 3D

Cell death is a phenomenon, frequently perceived as an absolute event for cell, tissue and the organ. However, the rising popularity and complexity of such 3D multicellular 'tissue building blocks' as heterocellular spheroids, organoids, and 'assembloids' prompts to revise the definition and quantification of cell viability and death. It raises several questions on the overall viability of all the cells within 3D volume and on choosing the appropriate, continuous, and non-destructive viability assay enabling for a single-cell analysis. In this review, we look at cell viability and cell death modalities with attention to the intrinsic features of such 3D models as spheroids, organoids, and bioprints. Furthermore, we look at emerging and promising methodologies, which can help define and understand the balance between cell viability and death in dynamic and complex 3D environments. We conclude that the recent innovations in biofabrication, biosensor probe development, and fluorescence microscopy can help answer these questions.

Fungus-derived protein particles as cell-adhesive matrices for cell-cultivated food

Cell-adhesive factors mediate adhesion of cells to substrates via peptide motifs such as the Arg-Gly-Asp (RGD) sequence. With the onset of sustainability issues, there is a pressing need to find alternatives to animal-derived cell-adhesive factors, especially for cell-cultivated food applications. In this paper, we show how data mining can be a powerful approach toward identifying fungal-derived cell-adhesive proteins and present a method to isolate and utilize these proteins as extracellular matrices (ECM) to support cell adhesion and culture in 3D. Screening of a protein database for fungal and plant proteins uncovered that ~5.5% of the unique reported proteins contain RGD sequences. A plot of fungi species vs RGD percentage revealed that 98% of the species exhibited an RGD percentage > = 1%. We observed the formation of protein particles in crude extracts isolated from basidiomycete fungi, which could be correlated to their stability towards particle aggregation at different temperatures. These protein particles were incorporated in 3D fiber matrices encapsulating mouse myoblast cells, showing a positive effect on cell alignment. We demonstrated a cell traction stress on the protein particles (from Flammulina velutipes) that was comparable to cells on fibronectin. A snapshot of the RGD-containing proteins in the fungal extracts was obtained by combining SDS-PAGE and mass spectrometry of the peptide fragments obtained by enzymatic cleavage. Therefore, a sustainable source of cell-adhesive proteins is widely available in the fungi kingdom. A method has been developed to identify candidate species and produce cell-adhesive matrices, applicable to the cell-cultivated food and healthcare industries.

Cassava microfiber-reinforced gelatin scaffold holds promise for tissue engineering by exhibiting cytocompatibility with HEK 293 cells

Cellulose fiber-reinforced composite scaffolds have recently become an interesting target for biomedical and tissue engineering (TE) applications. Cassava bagasse, a fibrous solid residue obtained after the extraction of cassava starch and soluble sugars, has been explored as a potential source of cellulose and has been successfully used to enhance the mechanical properties of gelatin scaffolds for TE purposes. This study assessed the cytocompatibility of the cassava microfiber-gelatin composite scaffold using human embryonic kidney cells (HEK 293) and a breast cancer cell line (MDA MB 231) under ISO 10993-5 standards. The viability of cells within the composite scaffold was analyzed through MTT assay. The growth of HEK 293, as well as the cell morphology, was not affected by the presence of cellulose within the composite, whereas the growth of breast cancer cells appeared to be inhibited with noticeable changes in cell morphology. These findings suggest that the presence of the cassava fiber in gelatin is not cytotoxic to HEK 293 cells. Thus, the composite is suitable for TE purposes when using normal cells. On the contrary, the presence of the fiber in gelatin elicited a cytotoxic effect in MDA MB 231 cells. Thus, the composite may not be considered for three-dimensional (3D) tumor cell studies requiring cancer cell growth. However, further studies are required to explore the use of the fiber from cassava bagasse for its anticancer cell properties, as observed in this study.

Decellularized Scaffolds of Nopal (Opuntia Ficus-indica) for Bioengineering in Regenerative Dentistry

Opuntia Ficus-indica, or nopal, is traditionally used for its medicinal properties in Mexico. This study aims to decellularize and characterize nopal (Opuntia Ficus-indica) scaffolds, assess their degradation and the proliferation of hDPSC, and determine potential pro-inflammatory effects by assessing the expression of cyclooxygenase 1 and 2 (COX-1 and 2). The scaffolds were decellularized using a 0.5% sodium dodecyl sulfate (SDS) solution and confirmed by color, optical microscopy, and SEM. The degradation rates and mechanical properties of the scaffolds were determined by weight and solution absorbances using trypsin and PBS and tensile strength testing. Human dental pulp stem cells (hDPSCs) primary cells were used for scaffold-cell interaction and proliferation assays, as well as an MTT assay to determine proliferation. Proinflammatory protein expression of COX-I and -II was discovered by Western blot assay, and the cultures were induced into a pro-inflammatory state with interleukin 1-β. The nopal scaffolds exhibited a porous structure with an average pore size of 252 ± 77 μm. The decellularized scaffolds showed a 57% reduction in weight loss during hydrolytic degradation and a 70% reduction during enzymatic degradation. There was no difference in tensile strengths between native and decellularized scaffolds (12.5 ± 1 and 11.8 ± 0.5 MPa). Furthermore, hDPSCs showed a significant increase in cell viability of 95% and 106% at 168 h for native and decellularized scaffolds, respectively. The combination of the scaffold and hDPSCs did not cause an increase in the expression of COX-1 and COX-2 proteins. However, when the combination was exposed to IL-1β, there was an increase in the expression of COX-2. This study demonstrates the potential application of nopal scaffolds in tissue engineering and regenerative medicine or dentistry, owing to their structural characteristics, degradation properties, mechanical properties, ability to induce cell proliferation, and lack of enhancement of pro-inflammatory cytokines.

Apple-derived 3D scaffold for improving gastrointestinal viability and in-situ growth of probiotics

This study develops a novel low-cost microbial delivery system by transforming common food materials such as apple tissue into a 3D scaffold. Apple tissue scaffold was constructed by decellularization of intact tissue using a minimal amount of sodium dodecyl sulfate (0.5 % w/v). Vacuum-assisted infusion of model probiotic Lactobacillus cells led to a high encapsulation yield of probiotic cells (10¹⁰ CFU/g of scaffold) in 3D scaffolds on a wet basis. The bio-polymer coated 3D scaffolds with infused cells significantly enhanced the survivability of infused probiotic cells during simulated gastric and intestinal digestions. In addition, imaging and plate counting results validate the growth of the infused cells in the 3D scaffold after 1-2 days of fermentation in MRS media, while cells without infusion in the scaffold had limited attachment with the intact apple tissue. Overall, these results highlight the potential of the apple tissue-derived 3D scaffold to deliver probiotic cells and include the biochemical compositions to support the growth of delivered microbial cells in the colon.

New vegetable-waste biomaterials by Lupin albus L. as cellular scaffolds for applications in biomedicine and food

The reprocessing of vegetal-waste represents a new research field in order to design novel biomaterials for potential biomedical applications and in food industry. Here we obtained a biomaterial from Lupinus albus L. hull (LH) that was characterized micro-structurally by scanning electron microscopy and for its antimicrobial and scaffolding properties. A good adhesion and proliferation of human mesenchymal stem cells (hMSCs) seeded on LH scaffold were observed. Thanks to its high content of cellulose and beneficial phytochemical substances, LH and its derivatives can represent an available source for fabrication of biocompatible and bioactive scaffolds. Therefore, a reprocessing protocol of LH was optimized for producing a new LH bioplastic named BPLH. This new biomaterial was characterized by chemico-physical analyses. The water uptake, degradability and antimicrobial properties of BPLH were evaluated, as well as the mechanical properties. A good adhesion and proliferation of both fibroblasts and hMSCs on BPLH were observed over 2 weeks, and immunofluorescence analysis of hMSCs after 3 weeks indicates an initial commitment toward muscle differentiation. Our work represents a new approach toward the recovery and valorization of the vegetal waste showing the remarkable properties of LH and BPLH as cellular waste-based scaffold with potential applications in cell-based food field as well as in medicine for topical patches in wound healing and bedsores treatment.

Key aspects for conception and construction of co-culture models of tumor-stroma interactions

The tumor microenvironment is crucial in the initiation and progression of cancers. The interplay between cancer cells and the surrounding stroma shapes the tumor biology and dictates the response to cancer therapies. Consequently, a better understanding of the interactions between cancer cells and different components of the tumor microenvironment will drive progress in developing novel, effective, treatment strategies. Co-cultures can be used to study various aspects of these interactions in detail. This includes studies of paracrine relationships between cancer cells and stromal cells such as fibroblasts, endothelial cells, and immune cells, as well as the influence of physical and mechanical interactions with the extracellular matrix of the tumor microenvironment. The development of novel co-culture models to study the tumor microenvironment has progressed rapidly over recent years. Many of these models have already been shown to be powerful tools for further understanding of the pathophysiological role of the stroma and provide mechanistic insights into tumor-stromal interactions. Here we give a structured overview of different co-culture models that have been established to study tumor-stromal interactions and what we have learnt from these models. We also introduce a set of guidelines for generating and reporting co-culture experiments to facilitate experimental robustness and reproducibility.

Decellularized Spinach Biomaterials Support Physiologically Relevant Mechanical Cyclic Strain and Prompt a Stretch-Induced Cellular Response

Recently, decellularized plant biomaterials have been explored for their use as tissue engineered substitutes. Herein, we expanded upon the investigation of the mechanical properties of these materials to explore their elasticity as many anatomical areas of the body require biomechanical dynamism. We first constructed a device to secure the scaffold and induce a strain within the physiological range of the normal human adult lung during breathing (12-20 movements/min; 10-20% elongation). Results showed that decellularized spinach leaves can support cyclic strain for 24 h and displayed heterogeneous local strain values (7.76-15.88%) as well as a Poisson's ratio (0.12) similar to that of mammalian lungs (10.67-19.67%; 0.01), as opposed to an incompressible homogeneous standard polymer (such as PDMS (10.85-12.71%; 0.4)). Imaging and mechanical testing showed that the vegetal scaffold exhibited strain hardening but maintained its structural architecture and water retention capacity, suggesting an unaltered porosity. Interestingly, we also showed that cells seeded on the scaffold can also sense the mechanical strain as demonstrated by a nuclear reorientation perpendicular to strain direction (63.3° compared to 41.2° for nonstretched cells), a nuclear location of YAP and increased expression of YAP target genes, a high cytoplasmic calcium level, and an elevated expression level of collagen genes (COL1A1, COL3A1, COL4A1, and COL6A) with an increased collagen secretion at the protein level. Taken together, these data demonstrated that decellularized plant leaf tissues have an inherent elastic property similar to that found in the mammalian system to which cells can sense and respond.

Cellulose-Based Composites as Scaffolds for Tissue Engineering: Recent Advances

Today, numerous studies have focused on the design of novel scaffolds for tissue engineering and regenerative medicine applications; however, several challenges still exist in terms of biocompatibility/cytocompatibility, degradability, cell attachment/proliferation, nutrient diffusion, large-scale production, and clinical translation studies. Greener and safer technologies can help to produce scaffolds with the benefits of cost-effectiveness, high biocompatibility, and biorenewability/sustainability, reducing their toxicity and possible side effects. However, some challenges persist regarding their degradability, purity, having enough porosity, and possible immunogenicity. In this context, naturally derived cellulose-based scaffolds with high biocompatibility, ease of production, availability, sustainability/renewability, and environmentally benign attributes can be applied for designing scaffolds. These cellulose-based scaffolds have shown unique mechanical properties, improved cell attachment/proliferation, multifunctionality, and enhanced biocompatibility/cytocompatibility, which make them promising candidates for tissue engineering applications. Herein, the salient developments pertaining to cellulose-based scaffolds for neural, bone, cardiovascular, and skin tissue engineering are deliberated, focusing on the challenges and opportunities.

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.

Graded-Three-Dimensional Cell-Encapsulating Hydrogel as a Potential Biologic Scaffold for Disc Tissue Engineering

BACKGROUND

Intervertebral disk (IVD) degeneration, which can cause lower back pain, is a major predisposing factor for disability and can be managed through multiple approaches. However, there is no satisfactory strategy currently available to reconstruct and recover the natural properties of IVDs after degeneration. As tissue engineering develops, scaffolds with embedded cell cultures have proved critical for the successful regeneration of IVDs.

METHODS

In this study, an integrated scaffold for IVD replacement was developed. Through scanning electron microscopy and other mechanical measurements, we characterized the physical properties of different hydrogels. In addition, we simulated the physiological structure of natural IVDs. Nucleus pulposus (NP) cells and annulus fibrosus-derived stem cells (AFSCs) were seeded in gelatin methacrylate (GelMA) hydrogel at different concentrations to evaluate cell viability and matrix expression.

RESULTS

It was found that different concentrations of GelMA hydrogel can provide a suitable environment for cell survival. However, hydrogels with different mechanical properties influence cell adhesion and extracellular matrix component type I collagen, type II collagen, and aggrecan expression.

CONCLUSION

This tissue-engineered IVD implant had a similar structure and function as the native IVD, with the inner area mimicking the NP tissue and the outer area mimicking the stratified annulus fibrosus tissue. The new integrated scaffold demonstrated a good simulation of disc structure. The preparation of efficient and regeneration-promoting tissue-engineered scaffolds is an important issue that needs to be explored in the future. It is hoped that this work will provide new ideas and methods for the further construction of functional tissue replacement discs.

Plant Tissue Parenchyma and Vascular Bundles Selectively Regulate Stem Cell Mechanosensing and Differentiation

Introduction

Plant tissues are plentiful, diverse, and due to convergent evolution are structurally similar to many animal tissues. Decellularized plant tissues feature microtopographies that resemble cancellous bone (porous parenchyma) and skeletal muscle (fibrous vascular bundles). However, the use of plant tissues as an inexpensive and abundant biomaterial for controlling stem cell behavior has not been widely explored.

Methods

Celery plant tissues were cut cross-sectionally (porous parenchyma) or longitudinally (fibrous vascular bundles) and decellularized. Human mesenchymal stem cells (MSCs) were then cultured atop plant tissues and confocal imaging of single cells was used to evaluate the early effects of microtopography on MSC adhesion, morphology, cytoskeletal alignment, Yes-associated protein (YAP) signaling, and downstream lineage commitment to osteogenic or myogenic phenotypes.

Results

Microtopography was conserved post plant tissue decellularization and MSCs attached and proliferated on plant tissues. MSCs cultured on porous parenchyma spread isotropically along the periphery of plant tissue pores. In contrast, MSCs cultured on vascular bundles spread anisotropically and aligned in the direction of fibrous vascular bundles. Differences in microtopography also influenced MSC nuclear YAP localization and actin anisotropy, with higher values observed on fibrous tissues. When exposed to osteogenic or myogenic culture medium, MSCs on porous parenchyma had a higher percentage of cells stain positive for bone biomarker alkaline phosphatase, whereas myoblast determination protein 1 (MyoD) was significantly upregulated for MSCs on fibrous vascular bundles.

Conclusions

Together, these results show that plant tissues are an abundant biomaterial with defined microarchitecture that can reproducibly regulate MSC morphology, mechanosensing, and differentiation.

Supplementary Information

The online version of this article contains supplementary material available 10.1007/s12195-022-00737-9.

Emulsion-templated microparticles with tunable stiffness and topology: Applications as edible microcarriers for cultured meat

Cultured meat has potential to diversify methods for protein production, but innovations in production efficiency will be required to make cultured meat a feasible protein alternative. Microcarriers provide a strategy to culture sufficient volumes of adherent cells in a bioreactor that are required for meat products. However, cell culture on inedible microcarriers involves extra downstream processing to dissociate cells prior to consumption. Here, we present edible microcarriers that can support the expansion and differentiation of myogenic cells in a single bioreactor system. To fabricate edible microcarriers with a scalable process, we used water-in-oil emulsions as templates for gelatin microparticles. We also developed a novel embossing technique to imprint edible microcarriers with grooved topology in order to test if microcarriers with striated surface texture can promote myoblast proliferation and differentiation in suspension culture. In this proof-of-concept demonstration, we showed that edible microcarriers with both smooth and grooved surface topologies supported the proliferation and differentiation of mouse myogenic C2C12 cells in a suspension culture. The grooved edible microcarriers showed a modest increase in the proliferation and alignment of myogenic cells compared to cells cultured on smooth, spherical microcarriers. During the expansion phase, we also observed the formation of cell-microcarrier aggregates or 'microtissues' for cells cultured on both smooth and grooved microcarriers. Myogenic microtissues cultured with smooth and grooved microcarriers showed similar characteristics in terms of myotube length, myotube volume fraction, and expression of myogenic markers. To establish feasibility of edible microcarriers for cultured meat, we showed that edible microcarriers supported the production of myogenic microtissue from C2C12 or bovine satellite muscle cells, which we harvested by centrifugation into a cookable meat patty that maintained its shape and exhibited browning during cooking. These findings demonstrate the potential of edible microcarriers for the scalable production of cultured meat in a single bioreactor.

In vitro and in vivo biocompatibility of decellularized cellulose scaffolds functionalized with chitosan and platelet rich plasma for tissue engineering applications

This study describes the fabrication of cellulose scaffold (CS) and cellulose-chitosan (CS/CHI) scaffolds from the immature endosperm of Borassus flabellifer (Linn.) (BF) loaded with platelet rich plasma (PRP). Thus, developed scaffolds were evaluated for their physicochemical and mechanical behavior, growth factor release and biological performance. Additionally, in vivo response was assessed in a sub cutaneous rat model to study vascularization, host inflammatory response and macrophage polarization. The results of this study demonstrated that CS and CS/CHI scaffolds with PRP demonstrated favorable physiochemical and morphogical properties. The scaffold groups CS-PRP and CS/CHI-PRP were able to release growth factors in a well sustained manner under physiological conditions. The presence of PRP in cellulosic scaffolds did show significant differences in their behavior when investigated under in vitro studies, where the release of diverse cytokines improved the cellular proliferation and differentiation of osteoblasts. Finally, the PRP enriched scaffolds when studied under in vivo conditions showed increased angiogenesis and re-epithelialization with adequate collagen deposition and tissue remodeling. Our results suggest that besides the conventional carrier systems, this new-generation of plant-based cellulosic scaffolds with/without any modification can serve as a suitable carrier for PRP encapsulation and release, which can be used in numerous tissue regenerative therapies.

Toward Plant Cyborgs: Hydrogels Incorporated onto Plant Tissues Enable Programmable Shape Control

Engineered living materials (ELMs) that incorporate living organisms and synthetic materials enable advanced functional properties. Here, we seek to create plant cyborgs by combining plants or plant tissues with stimuli-responsive polymeric materials. Plant tissues with integrated shape control may find applications in regenerative medicine, and the shape control of living plants enables another dimension of adaptability and response to environmental threats, which can be applied to next-generation precision farming. In this work, we develop chemistry to integrate stimuli-responsive poly(N-isopropylacrylamide) (PNIPAM) hydrogels with decellularized plant tissues assisted by 3D printing. We demonstrate programmable shape morphing in response to thermal cues and ultraviolet (UV) light. Specifically, by taking advantage of the extrusion-based 3D printing method, we deposit nanocomposite PNIPAM precursors onto silane-treated decellularized leaf surface with prescribed shapes and spatial control. When subjected to external stimuli, the strain mismatch generated between the swellable nanocomposite PNIPAM and nonswellable decellularized leaf enables folding and bending to occur. This strategy to integrate the plant tissues with stimuli-responsive hydrogels allows the control of leaf morphology, opening avenues for plant-based biosensors and soft actuators to enhance food security; such materials also may find applications in biomedicine as tissue-engineering scaffolds.

Biomaterial and biocompatibility evaluation of tunicate nanocellulose for tissue engineering

Extracellular matrix fibril components, such as collagen, are crucial for the structural properties of several tissues and organs. Tunicate-derived cellulose nanofibrils (TNC) combined with living cells could become the next gold standard for cartilage and soft-tissue repair, as TNC fibrils present similar dimensions to collagen, feasible industrial production, and chemically straightforward and cost-efficient extraction procedures. In this study, we characterized the physical properties of TNC derived from aquaculture production in Norwegian fjords and evaluated its biocompatibility regarding induction of an inflammatory response and foreign-body reactions in a Wistar rat model. Additionally, histologic and immunohistochemical analyses were performed for comparison with expanded polytetrafluoroethylene (ePTFE) as a control. The average length of the TNC as determined by atomic force microscopy was tunable from 3 μm to 2.4 μm via selection of a various number of passages through a microfluidizer, and rheologic analysis showed that the TNC hydrogels were highly shear-thinning and with a viscosity dependent on fibril length and concentration. As a bioink, TNC exhibited excellent rheological and printability properties, with constructs capable of being printed with high resolution and fidelity. We found that post-print cross-linking with alginate stabilized the construct shape and texture, which increased its ease of handling during surgery. Moreover, after 30 days in vivo, the constructs showed a highly-preserved shape and fidelity of the grid holes, with these characteristics preserved after 90 days and with no signs of necrosis, infection, acute inflammation, invasion of neutrophil granulocytes, or extensive fibrosis. Furthermore, we observed a moderate foreign-body reaction involving macrophages, lymphocytes, and giant cells in both the TNC constructs and PTFE controls, although TNC was considered a non-irritant biomaterial according to ISO 10993-6 as compared with ePTFE. These findings represent a milestone for future clinical application of TNC scaffolds for tissue repair. One sentence summary: In this study, the mechanical properties of tunicate nanocellulose are superior to nanocellulose extracted from other sources, and the biocompatibility is comparable to that of ePTFE.

Surface Modification of Decellularized Natural Cellulose Scaffolds with Organosilanes for Bone Tissue Regeneration

The utility of plant tissues as scaffolding materials has been gaining significant interest in recent years owing to their unique material characteristics that are ideal for tissue regeneration. In this study, the degradation and biocompatibility of natural cellulosic scaffolds derived from Borassus flabellifer (Linn.) (BF) immature endosperm was improved by chemical oxidation and surface functionalization processes. Briefly, thus obtained cellulosic scaffolds were sequentially processed via a detergent exchange decellularization process followed by sodium periodate mediated oxidation and organosilane-based surface modification using amino (NH₂)-terminated 3-aminopropyltriethoxysilane (APTES) and methyl (CH₃)-terminated octadecyltrichlorosilane (OTS). Post oxidation and surface functionalization, the scaffolds showed improved physiochemical, morphological, and mechanical properties. Especially, the swelling capacity, total porosity, surface area, degradation kinetics, and mechanical behavior of scaffold were significantly higher in modified scaffold groups. The biocompatibility analysis demonstrated excellent cellular adhesion, proliferation and differentiation of osteoblasts with an evident upregulation of mineralization. Subcutaneous implantation of these scaffolds in a rat model demonstrated active angiogenesis, enhanced degradation, and excellent biocompatibility with concomitant deposition of a collagen matrix. Taken together, the native cellulosic scaffolds post chemical oxidation and surface functionalization can exclusively integrate the potential properties of native soft tissue with ameliorated in vitro and in vivo support in bone tissue engineering for nonloading bearing applications.

Natural Plant Tissue with Bioinspired Nano Amyloid and Hydroxyapatite as Green Scaffolds for Bone Regeneration

Bone defects have been increasingly prevalent around the globe and traditional bone substitutes are constantly limited by low abundance and biosafety due to their animal-based resources. Plant-based scaffolds are currently studied as a green candidate but the bioinertia of cellulose to mammalian cells leads to uncertain bone regeneration. Inspired by the cross-kingdom adhesion of plants and bacteria, this work proposes a concept of a novel plant bone substitute, involving coating decellularized plant with nano amyloids and nano hydroxyapatites, to bridge the plant scaffold and animal tissue regeneration. Natural microporosity of plants can guide alignment of mammalian cells into various organ-like structures. Taking advantage of the bioactive nano amyloids, the scaffolds drastically promote cell adhesion, viability, and proliferation. The enhanced bio-affinity is elucidated as positively charged nano amyloids and serum deposition on the nanostructure. Nano-hydroxyapatite crystals deposited on amyloid further prompt osteogenic differentiation of pre-osteoblasts. In vivo experiments prove successful trabeculae regeneration in the scaffold. Such a hierarchical design leverages the dedicated microstructure of natural plants and high bioactivity of nano amyloid/hydroxyapatite coatings, and addresses the abundant resource of bone substitutes. Not limited to their current application, plant materials functionalized with nano amyloid/hydroxyapatite coatings allow many cross-kingdom tissue engineering and biomedical applications.

Decellularized Alstroemeria flower stem modified with chitosan for tissue engineering purposes: A cellulose/chitosan scaffold

Utilizing plant-based scaffolds has pulled in the consideration of tissue engineers. Plant tissues own different structures with particular porosity and structure. In this study, the stem of the Alstroemeria flower was designated for decellularization to fabricate a new scaffold. The stems were decellularized and called AFSP and then modified by chitosan and named AFSPC. Osteoblast precursor cell line was employed to assess the biological potential of the final scaffolds. The results uncovered that AFSP owns linear microchannels with a smooth surface. AFSPC delineated uniform chitosan coating on the walls with appropriate roughness. AFSPC showed higher potential in swelling, degradation, diffusion, and having a porous structure than AFSP. Modification with chitosan improved mechanical behavior. Biological assays depicted no cytotoxicity for AFSP and AFSPC. AFSPC showed good cell attachment, proliferation, and migration. In conclusion, modified tissue plants can be a good candidate for tissue engineering of both soft and hard tissues.

Extracellular Matrix and the Production of Cultured Meat

Cultured meat production is an evolving method of producing animal meat using tissue engineering techniques. Cells, chemical factors, and suitable biomaterials that serve as scaffolds are all essential for the cultivation of muscle tissue. Scaffolding is essential for the development of organized meat products resembling steaks because it provides the mechanical stability needed by cells to attach, differentiate, and mature. In in vivo settings, extracellular matrix (ECM) ensures substrates and scaffolds are provided for cells. The ECM of skeletal muscle (SM) maintains tissue elasticity, creates adhesion points for cells, provides a three-dimensional (3D) environment, and regulates biological processes. Consequently, creating mimics of native ECM is a difficult task. Animal-derived polymers like collagen are often regarded as the gold standard for producing scaffolds with ECM-like properties. Animal-free scaffolds are being investigated as a potential source of stable, chemically defined, low-cost materials for cultured meat production. In this review, we explore the influence of ECM on myogenesis and its role as a scaffold and vital component to improve the efficacy of the culture media used to produce cultured meat.

Homemade bread: Repurposing an ancient technology for in vitro tissue engineering

Numerous biomaterial scaffolds have been developed which provide architectures to support the proliferation of mammalian cells. Scaffolds derived from plant components have been utilized in several tissue engineering applications, including the production of cultured meats. Bread crumb is a common ingredient employed as a texturizer and filler in existing manufacturing processes for the production of animal meat products. Though an unconventional choice as a scaffolding material, we developed a yeast-free "soda bread" with controllable porosity and mechanical properties which is stable over several weeks in culture with fibroblasts, myoblasts and pre-osteoblasts. All cells were able to proliferate throughout the three-dimensional scaffolds, depositing extra-cellular matrix while exhibiting low stress and high viability. Importantly, myoblasts were also able to differentiate into myotubes, a key step required for the culture of skeletal muscle tissue. The results suggest opportunities for the dual-use possibility of utilizing existing texturizer and filler components in future lab grown meat products, however this will of course require further validation. Regardless, the bread-derived scaffolds presented here are simply produced, inherently edible and support muscle tissue engineering, qualities which highlight their utility in the production of future meat products.

A Novel Plant Leaf Patch Absorbed With IL-33 Antibody Decreases Venous Neointimal hyperplasia

Introduction: We recently showed that a decellularized leaf scaffold can be loaded with polylactic-co-glycolic acid (PLGA)-based rapamycin nanoparticles, this leaf patch can then inhibit venous neointimal hyperplasia in a rat inferior vena cava (IVC) venoplasty model. IL-33 plays a role in the neointimal formation after vascular injury. We hypothesized that plant leaves can absorb therapeutic drug solution and can be used as a patch with drug delivery capability, and plant leaves absorbed with IL-33 antibody can decrease venous neointimal hyperplasia in the rat IVC venoplasty model. Method: A human spiral saphenous vein (SVG) graft implanted in the popliteal vein was harvested from a patient with trauma and analyzed by immunofluorescence. Male Sprague-Dawley rats (aged 6-8 weeks) were used to create the IVC patch venoplasty model. Plant leaves absorbed with rhodamine, distilled water (control), rapamycin, IL-33, and IL-33 antibody were cut into patches (3 × 1.5 mm²) and implanted into the rat IVC. Patches were explanted at day 14 for analysis. Result: At day 14, in the patch absorbed with rhodamine group, immunofluorescence showed rhodamine fluorescence in the neointima, inside the patch, and in the adventitia. There was a significantly thinner neointima in the plant patch absorbed with rapamycin (p = 0.0231) compared to the patch absorbed with distilled water. There was a significantly large number of IL-33 (p = 0.006) and IL-1β (p = 0.012) positive cells in the human SVG neointima compared to the human great saphenous vein. In rats, there was a significantly thinner neointima, a smaller number of IL-33 (p = 0.0006) and IL-1β (p = 0.0008) positive cells in the IL-33 antibody-absorbed patch group compared to the IL-33-absorbed patch group. Conclusion: We found that the natural absorption capability of plant leaves means they can absorb drug solution efficiently and can also be used as a novel drug delivery system and venous patch. IL-33 plays a role in venous neointimal hyperplasia both in humans and rats; neutralization of IL-33 by IL-33 antibody can be a therapeutic method to decrease venous neointimal hyperplasia.

The Emerging Role of Decellularized Plant-Based Scaffolds as a New Biomaterial

The decellularization of plant-based biomaterials to generate tissue-engineered substitutes or in vitro cellular models has significantly increased in recent years. These vegetal tissues can be sourced from plant leaves and stems or fruits and vegetables, making them a low-cost, accessible, and sustainable resource from which to generate three-dimensional scaffolds. Each construct is distinct, representing a wide range of architectural and mechanical properties as well as innate vasculature networks. Based on the rapid rise in interest, this review aims to detail the current state of the art and presents the future challenges and perspectives of these unique biomaterials. First, we consider the different existing decellularization techniques, including chemical, detergent-free, enzymatic, and supercritical fluid approaches that are used to generate such scaffolds and examine how these protocols can be selected based on plant cellularity. We next examine strategies for cell seeding onto the plant-derived constructs and the importance of the different functionalization methods used to assist in cell adhesion and promote cell viability. Finally, we discuss how their structural features, such as inherent vasculature, porosity, morphology, and mechanical properties (i.e., stiffness, elasticity, etc.) position plant-based scaffolds as a unique biomaterial and drive their use for specific downstream applications. The main challenges in the field are presented throughout the discussion, and future directions are proposed to help improve the development and use of vegetal constructs in biomedical research.