Ternary Aligned Nanofibers of RGD Peptide-Displaying M13 Bacteriophage/PLGA/Graphene Oxide for Facilitated Myogenesis

Intra-abdominal transplantation of PLGA/PCL/M13 phage electrospun scaffold induces self-assembly of lymphoid tissue-like structure

Lymphoid organs are the main structural components of the immune system. In the current research, the mixture of poly lactic-co-glycolic acid (PLGA), polycaprolactone (PCL), and M13 phage or its RGD-modified form was used in the construction of a fibrillar scaffold using the electrospinning method. The constructs were transplanted intra-abdominally and examined for the formation of lymphoid-like tissues at different time intervals. The confocal and scanning electron microscopy demonstrate that M13 phage-containing scaffolds provide a suitable environment for lymph node-isolated fibroblasts. Morphological analysis demonstrate the formation of lymph node-like tissues in the M13 phage-containing scaffolds after transplantation. Histological analysis confirm both blood and lymph angiogenesis in the implanted construct and migration of inflammatory cells to the M13 phage-containing scaffolds. In addition, flow cytometry and immunohistochemistry analysis showed the homing and compartmentalization of dendritic cells (DCs), B and T lymphocytes within the PLGA/PCL/M13 phage-RGD based scaffolds and similar to what is seen in the mouse lymphoid tissues. It seems that the application of M13 phage could improve the generation of functional lymphoid tissues in the electrospun scaffolds and could be used for lymphoid tissue regeneration.

Living virus-based nanohybrids for biomedical applications

Living viruses characterized by distinctive biological functions including specific targeting, gene invasion, immune modulation, and so forth have been receiving intensive attention from researchers worldwide owing to their promising potential for producing numerous theranostic modalities against diverse pathological conditions. Nevertheless, concerns during applications, such as rapid immune clearance, altering immune activation modes, insufficient gene transduction efficiency, and so forth, highlight the crucial issues of excessive therapeutic doses and the associated biosafety risks. To address these concerns, synthetic nanomaterials featuring unique physical/chemical properties are frequently exploited as efficient drug delivery vehicles or treatments in biomedical domains. By constant endeavor, researchers nowadays can create adaptable living virus-based nanohybrids (LVN) that not only overcome the limitations of virotherapy, but also combine the benefits of natural substances and nanotechnology to produce novel and promising therapeutic and diagnostic agents. In this review, we discuss the fundamental physiochemical properties of the viruses, and briefly outline the basic construction methodologies of LVN. We then emphasize their distinct diagnostic and therapeutic performances for various diseases. Furthermore, we survey the foreseeable challenges and future perspectives in this interdisciplinary area to offer insights. This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.

MXene and Xene: promising frontier beyond graphene in tissue engineering and regenerative medicine

The emergence of 2D nanomaterials (2D NMs), which was initiated by the isolation of graphene (G) in 2004, revolutionized various biomedical applications, including bioimaging and -sensing, drug delivery, and tissue engineering, owing to their unique physicochemical and biological properties. Building on the success of G, a novel class of monoelemental 2D NMs, known as Xenes, has recently emerged, offering distinct advantages in the fields of tissue engineering and regenerative medicine. In this review, we focus on the comparison of G and Xene materials for use in fabricating tissue engineering scaffolds. After a brief introduction to the basic physicochemical properties of these materials, recent representative studies are classified in terms of the engineered tissue, i.e., bone, cartilage, neural, muscle, and skin tissues. We analyze several methods of improving the clinical potential of Xene-laden scaffolds using state-of-the-art fabrication technologies and innovative biomaterials. Despite the considerable advantages of Xene materials, critical concerns, such as biocompatibility, biodistribution and regulatory challenges, should be considered. This review and collaborative efforts should advance the field of Xene-based tissue engineering and enable innovative, effective solutions for use in future tissue regeneration.

Rhabdomyosarcoma: Current Therapy, Challenges, and Future Approaches to Treatment Strategies

Rhabdomyosarcoma is a rare cancer arising in skeletal muscle that typically impacts children and young adults. It is a worldwide challenge in child health as treatment outcomes for metastatic and recurrent disease still pose a major concern for both basic and clinical scientists. The treatment strategies for rhabdomyosarcoma include multi-agent chemotherapies after surgical resection with or without ionization radiotherapy. In this comprehensive review, we first provide a detailed clinical understanding of rhabdomyosarcoma including its classification and subtypes, diagnosis, and treatment strategies. Later, we focus on chemotherapy strategies for this childhood sarcoma and discuss the impact of three mechanisms that are involved in the chemotherapy response including apoptosis, macro-autophagy, and the unfolded protein response. Finally, we discuss in vivo mouse and zebrafish models and in vitro three-dimensional bioengineering models of rhabdomyosarcoma to screen future therapeutic approaches and promote muscle regeneration.

Cytocompatible and biodegradable poly(d,l-lactide-coglycolide)/reduced graphene oxide scaffolds

Applications of graphene in regenerative medicine have attracted the increasing attention of numerous research groups due to the specific properties that confers on biomaterials. In this paper, the degradation behavior of poly(d,l-lactide-co-glycolide (PLGA)/reduced graphene oxide (rGO) scaffolds obtained by thermally induced phase separation (TIPS) and lyophilization was studied in phosphate buffered saline (PBS) solution, at 37 °C during eight weeks. Additionally, the cytotoxicity of the different samples through the metabolic activity of L929 fibroblast cells was also addressed. Scanning electron microscopy tests show that the addition of rGO particles increases the pore size from 60 to 100 µm as well as their morphological definition. Scaffolds with 0.6 and 1% rGO concentrations lost more mass than those with lower filler content, that is, they degraded more quickly. The results obtained by differential scanning calorimetry indicate that the rGO particles restrict the movement of the macromolecular chain segments due to the formation of hydrogen bonds and electrostatic attraction. The electrical conductivity tests show that the addition of rGO leads to a rapid transition from insulating to conductive scaffolds with a percolation value of ≈ 0.5 w/w. All the different PLGA samples with different rGO content up to 1% present no cytotoxic behaviour for L929 fibroblast cells, being therefor suitable for biomedical applications.

Engineered M13 phage as a novel therapeutic bionanomaterial for clinical applications: From tissue regeneration to cancer therapy

Bacteriophages (phages) are nanostructured viruses with highly selective antibacterial properties that have gained attention beyond eliminating bacteria. Specifically, M13 phages are filamentous phages that have recently been studied in various aspects of nanomedicine due to their biological advantages and more compliant engineering capabilities over other phages. Having nanofiber-like morphology, M13 phages can reach varied target sites and self-assemble into multidimensional scaffolds in a relatively safe and stable way. In addition, genetic modification of the coat proteins enables specific display of peptides and antibodies on the phages, allowing for precise and individualized medicine. M13 phages have also been subjected to novel engineering approaches, including phage-based bionanomaterial engineering and phage-directed nanomaterial combinations that enhance the bionanomaterial properties of M13 phages. In view of these features, researchers have been able to utilize M13 phages for therapeutic applications such as drug delivery, biodetection, tissue regeneration, and targeted cancer therapy. In particular, M13 phages have been utilized as a novel bionanomaterial for precisely mimicking natural tissue environment in order to overcome the shortage in tissue and organ donors. Hence, in this review, we address the recent studies and advances of using M13 phages in the field of nanomedicine as therapeutic agents based upon their characteristics as novel bionanomaterial with biomolecules displayed. This paper also emphasizes the novel engineering approach that enhances M13 phage's bionanomaterial capabilities. Current limitations and future approaches are also discussed to provide insight in further progress for M13 phage-based clinical applications.

Recent advances of graphene-biomacromolecule nanocomposites in medical applications

In recent years, graphene-based composites have received increasing attention due to their high biocompatibility, large specific surface area, high electrical conductivity and unique mechanical properties. The combination of biomacromolecules and graphene provides a promising route for the preparation of novel graphene-based nanocomposites. Novel graphene-based nanocomposites with unique functions could be applied to medicine, biology, biosensors, environmental science, energy storage and other fields. Graphene-biomacromolecule nanocomposites have excellent biocompatibility, outstanding biofunctionality and low cytotoxicity, and have more advantages and development prospects than other traditional graphene-based materials in biological and biomedical fields. In this work, we summarize the research on the covalent and non-covalent interactions between different biomacromolecules (peptides, DNA/RNA, proteins and enzymes) and graphene, as well as the synthesis methods of novel functionalized graphene-biomacromolecule composites in recent years. We mainly introduce the recent advances (last 5 years) of graphene-biomacromolecule nanocomposites in medical applications, such as medical detection and disease treatment. We hope that this review will help readers to understand the methods and mechanisms of biomolecules modifying the surface of graphene, as well as the synthesis and application of graphene-based nanocomposites, which will promote the future developments of graphene-biomolecule composites in biomedicine, tissue engineering, materials engineering, and so on.

Effect of Boron-Doped Mesoporous Bioactive Glass Nanoparticles on C2C12 Cell Viability and Differentiation: Potential for Muscle Tissue Application

Mesoporous bioactive glasses (MBGs) exhibit a high surface area and a highly ordered mesoporous structure. MBGs have potential for both hard and soft tissue engineering applications. MBGs may be doped with biologically active ions to tailor their biological activity. Boron is being widely studied as a dopant of bioactive glasses. Recently, research has demonstrated the potential of boron-containing bioactive glasses for muscle regeneration. In this study, boron-containing MBGs, 10B-MBG and 18B-MBG nanoparticles, were produced by a microemulsion-assisted sol-gel approach for potential muscle regeneration applications. First, X-ray diffraction (XRD), Fourier transform infrared (FTIR), and energy-dispersive X-ray spectroscopy (EDX) analyses were conducted to study the chemical structure and composition of the nanoparticles. To examine the nanoparticle morphology, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images were analyzed. Both SEM images and particle size distribution determined by dynamic light scattering (DLS) indicated a decrease of the average particle size after boron doping. TEM images indicated a slit-shaped mesoporous structure of nanoparticles for all compositions. The ζ potential was measured, and a negative surface charge was found for all study groups due to the presence of silanol groups. Cytocompatibility and fluorescence microscopy studies were also carried out. The results indicated that low concentrations (0.1 and 1 mg mL^-1) of all MBG nanoparticles led to high viability of C2C12 cells. Fluorescence microscopy images indicated that at lower nanoparticle concentrations (0.1 and 1 mg mL^-1), C2C12 cells appeared to differentiate into myotubes, which was indicated by a spindle-shaped morphology. For 10 mg mL^-1 concentration of nanoparticles, C2C12 cells had a lower aspect ratio (estimated qualitatively by inspection of the images), which implied a lower degree of differentiation. Boron-doped MBG nanoparticles in reduced concentrations are suitable to induce differentiation of C2C12 cells into myotubes, indicating their potential for applications in muscle tissue repair.

Ternary MXene-loaded PLCL/collagen nanofibrous scaffolds that promote spontaneous osteogenic differentiation

Conventional bioinert bone grafts often have led to failure in osseointegration due to low bioactivity, thus much effort has been made up to date to find alternatives. Recently, MXene nanoparticles (NPs) have shown prominent results as a rising material by possessing an osteogenic potential to facilitate the bioactivity of bone grafts or scaffolds, which can be attributed to the unique repeating atomic structure of two carbon layers existing between three titanium layers. In this study, we produced MXene NPs-integrated the ternary nanofibrous matrices of poly(L-lactide-co-ε-caprolactone, PLCL) and collagen (Col) decorated with MXene NPs (i.e., PLCL/Col/MXene), as novel scaffolds for bone tissue engineering, via electrospinning to explore the potential benefits for the spontaneous osteogenic differentiation of MC3T3-E1 preosteoblasts. The cultured cells on the physicochemical properties of the nanofibrous PLCL/Col/MXene-based materials revealed favorable interactions with the supportive matrices, highly suitable for the growth and survival of preosteoblasts. Furthermore, the combinatorial ternary material system of the PLCL/Col/MXene nanofibers obviously promoted spontaneous osteodifferentiation with positive cellular responses by providing effective microenvironments for osteogenesis. Therefore, our results suggest that the unprecedented biofunctional advantages of the MXene-integrated PLCL/Col nanofibrous matrices can be expanded to a wide range of strategies for the development of effective scaffolds in bone tissue regeneration.

Transformation of nanoparticles into compacts: A study on PLGA and celecoxib nanoparticles

Oral delivery of nanoparticles possesses many advantages for delivery of active pharmaceutical ingredients (APIs) to the gastrointestinal tract. However, the poor physical stability of nanoparticles in liquid state is often a challenge. Removing water from the nanosuspensions and transforming the nanoparticles into solid particulate matter in the form of, e.g., tablets could be a potential approach to increase the stability of nanoparticles. The aim of this study was to transform nanoparticles into compacts and to investigate the redispersion of nanoparticles from compacts as well as the dissolution behavior of these compacts. DL-lactide-co-glycolide copolymer (PLGA) nanoparticles and celecoxib (CLX) nanoparticles were used as two model nanoparticle systems and fabricated into nano-embedded microparticles (NEMs) and subsequently compressed into compacts. The compacts were evaluated with respect to the redispersibility of the nanoparticles, as well as the dissolution characteristics of CLX. The results showed that the NEMs could be readily compressed into compacts with sufficient mechanical strength. The size of the redispersed PLGA nanoparticles from the compacts using 2-hydroxypropyl-β-cyclodextrin (HPβCD) as stabilizer was comparable to the original nanoparticles. In contrast, the redispersibility of CLX nanoparticles from the compacts was not as effective as for the PLGA nanoparticles evidenced by a significant increase in the size and polydispersity index (PDI) of the redispersed nanoparticles. Nonetheless, an obvious enhancement in dissolution rate of CLX was observed from the compacts with CLX nanoparticles. It is concluded that transforming polymeric nanoparticles into compacts via NEMs provides stabilization and allows redispersion into original nanoparticles. Despite the reduced redispersibility, compacts loaded with nanoparticles exhibited improved dissolution rate compared with the crystalline drug. Loading of nanoparticles into compacts is a promising approach to overcome the poor stability of nanoparticle within oral drug delivery of nanoparticles.

The intrinsic piezoelectric properties of materials - a review with a focus on biological materials

Piezoelectricity, a linear electromechanical coupling, is of great interest due to its extensive applications including energy harvesters, biomedical, sensors, and automobiles. A growing amount of research has been done to investigate the energy harvesting potential of this phenomenon. Traditional piezoelectric inorganics show high piezoelectric outputs but are often brittle, inflexible and may contain toxic compounds such as lead. On the other hand, biological piezoelectric materials are biodegradable, biocompatible, abundant, low in toxicity and are easy to fabricate. Thus, they are useful for many applications such as tissue engineering, biomedical and energy harvesting. This paper attempts to explain the basis of piezoelectricity in biological and non-biological materials and research involved in those materials as well as applications and limitations of each type of piezoelectric material.

Piezoelectricity, a linear electromechanical coupling, is of great interest due to its extensive applications including energy harvesters, biomedical, sensors, and automobiles.

Recent advances in the synthesis and applications of graphene-polypeptide nanocomposites

The combination of peptides and graphene-derived materials provides a new way to prepare graphene-based nanocomposites with unique structures, properties, and functions. The modification of graphene with different polypeptides not only improves the biocompatibility and biological recognition ability of graphene-based materials, but also greatly expands their application fields. In this work, we summarize different interactions between graphene and polypeptides, and the synthesis methods of novel functional graphene-polypeptide nanocomposites based on the interactions in recent years (from 2016 to present). In addition, the potential applications of graphene-peptide hybrid nanocomposites in biomedicine, tissue engineering, biosensors, environmental science engineering, optoelectronic materials, and energy storage are introduced. We hope that this review will help readers to understand the methods and mechanisms of the modification of graphene surfaces with biomolecules, and promote readers to understand the synthesis and applications of graphene-based nanocomposites. This work may provide hints and references for the development of peptide sequence design, and biomedical and functional materials, and will help in designing and synthesizing novel graphene-based nanomaterials with unique properties and suitable for various applications in the future.

Reduced graphene oxide coating enhances osteogenic differentiation of human mesenchymal stem cells on Ti surfaces

BACKGROUND

Titanium (Ti) has been utilized as hard tissue replacement owing to its superior mechanical and bioinert property, however, lack in tissue compatibility and biofunctionality has limited its clinical use. Reduced graphene oxide (rGO) is one of the graphene derivatives that possess extraordinary biofunctionality and are known to induce osseointegration in vitro and in vivo. In this study, rGO was uniformly coated by meniscus-dragging deposition (MDD) technique to fabricate rGO-Ti substrate for orthopedic and dental implant application.

METHODS

The physicochemical characteristics of rGO-coated Ti (rGO-Ti) substrates were evaluated by atomic force microscopy, water contact angle, and Raman spectroscopy. Furthermore, human mesenchymal stem cells (hMSCs) were cultured on the rGO-Ti substrate, and then their cellular behaviors such as growth and osteogenic differentiation were determined by a cell counting kit-8 assay, alkaline phosphatase (ALP) activity assay, and alizarin red S staining.

RESULTS

rGO was coated uniformly on Ti substrates by MDD process, which allowed a decrease in the surface roughness and contact angle of Ti substrates. While rGO-Ti substrates significantly increased cell proliferation after 7 days of incubation, they significantly promoted ALP activity and matrix mineralization, which are early and late differentiation markers, respectively.

CONCLUSION

It is suggested that rGO-Ti substrates can be effectively utilized as dental and orthopedic bone substitutes since these graphene derivatives have potent effects on stimulating the osteogenic differentiation of hMSCs and showed superior bioactivity and osteogenic potential.

DNA Nanostructures and DNA-Functionalized Nanoparticles for Cancer Theranostics

In the last two decades, DNA has attracted significant attention toward the development of materials at the nanoscale for emerging applications due to the unparalleled versatility and programmability of DNA building blocks. DNA-based artificial nanomaterials can be broadly classified into two categories: DNA nanostructures (DNA-NSs) and DNA-functionalized nanoparticles (DNA-NPs). More importantly, their use in nanotheranostics, a field that combines diagnostics with therapy via drug or gene delivery in an all-in-one platform, has been applied extensively in recent years to provide personalized cancer treatments. Conveniently, the ease of attachment of both imaging and therapeutic moieties to DNA-NSs or DNA-NPs enables high biostability, biocompatibility, and drug loading capabilities, and as a consequence, has markedly catalyzed the rapid growth of this field. This review aims to provide an overview of the recent progress of DNA-NSs and DNA-NPs as theranostic agents, the use of DNA-NSs and DNA-NPs as gene and drug delivery platforms, and a perspective on their clinical translation in the realm of oncology.

Engineered Bacteriophages for Practical Applications

The diversity of advanced genetic engineering techniques that have become available in recent years has enabled a more precise manipulation of genes and genomes. Among these, bacteriophage genomes stand out as an interesting target due to their dependence on a host for replication, which previously complicated their manipulation, and due as well to the many possible fields in which they can be used. In this review, we highlight recent applications for which genetically modified bacteriophages are being employed: as phage therapy in medicine, animal industries and agricultural settings; as a source of new antimicrobials; as biosensors for research, health and environmental purposes; and as genetic engineering tools themselves.

Advanced Techniques for Skeletal Muscle Tissue Engineering and Regeneration

Tissue engineering has recently emerged as a novel strategy for the regeneration of damaged skeletal muscle tissues due to its ability to regenerate tissue. However, tissue engineering is challenging due to the need for state-of-the-art interdisciplinary studies involving material science, biochemistry, and mechanical engineering. For this reason, electrospinning and three-dimensional (3D) printing methods have been widely studied because they can insert embedded muscle cells into an extracellular-matrix-mimicking microenvironment, which helps the growth of seeded or laden cells and cell signals by modulating cell–cell interaction and cell–matrix interaction. In this mini review, the recent research trends in scaffold fabrication for skeletal muscle tissue regeneration using advanced techniques, such as electrospinning and 3D bioprinting, are summarized. In conclusion, the further development of skeletal muscle tissue engineering techniques may provide innovative results with clinical potential for skeletal muscle regeneration.

Nanomaterial Additives for Fabrication of Stimuli-Responsive Skeletal Muscle Tissue Engineering Constructs

Volumetric muscle loss necessitates novel tissue engineering strategies for skeletal muscle repair, which have traditionally involved cells and extracellular matrix-mimicking scaffolds and have thus far been unable to successfully restore physiologically relevant function. However, the incorporation of various nanomaterial additives with unique physicochemical properties into scaffolds has recently been explored as a means of fabricating constructs that are responsive to electrical, magnetic, and photothermal stimulation. Herein, several classes of nanomaterials that are used to mediate external stimulation to tissue engineered skeletal muscle are reviewed and the impact of these stimuli-responsive biomaterials on cell growth and differentiation and in vivo muscle repair is discussed. The degradation kinetics and biocompatibilities of these nanomaterial additives are also briefly examined and their potential for incorporation into clinically translatable skeletal muscle tissue engineering strategies is considered. Overall, these nanomaterial additives have proven efficacious and incorporation in tissue engineering scaffolds has resulted in enhanced functional skeletal muscle regeneration.

3D Graphene Scaffolds for Skeletal Muscle Regeneration: Future Perspectives

Although skeletal muscle can regenerate after injury, in chronic damages or in traumatic injuries its endogenous self-regeneration is impaired. Consequently, tissue engineering approaches are promising tools for improving skeletal muscle cells proliferation and engraftment. In the last decade, graphene and its derivates are being explored as novel biomaterials for scaffolds production for skeletal muscle repair. This review describes 3D graphene-based materials that are currently used to generate complex structures able not only to guide cell alignment and fusion but also to stimulate muscle contraction thanks to their electrical conductivity. Graphene is an allotrope of carbon that has indeed unique mechanical, electrical and surface properties and has been functionalized to interact with a wide range of synthetic and natural polymers resembling native musculoskeletal tissue. More importantly, graphene can stimulate stem cell differentiation and has been studied for cardiac, neuronal, bone, skin, adipose, and cartilage tissue regeneration. Here we recapitulate recent findings on 3D scaffolds for skeletal muscle repairing and give some hints for future research in multifunctional graphene implants.

Recent Advances in Organic Piezoelectric Biomaterials for Energy and Biomedical Applications

The past decade has witnessed significant advances in medically implantable and wearable devices technologies as a promising personal healthcare platform. Organic piezoelectric biomaterials have attracted widespread attention as the functional materials in the biomedical devices due to their advantages of excellent biocompatibility and environmental friendliness. Biomedical devices featuring the biocompatible piezoelectric materials involve energy harvesting devices, sensors, and scaffolds for cell and tissue engineering. This paper offers a comprehensive review of the principles, properties, and applications of organic piezoelectric biomaterials. How to tackle issues relating to the better integration of the organic piezoelectric biomaterials into the biomedical devices is discussed. Further developments in biocompatible piezoelectric materials can spark a new age in the field of biomedical technologies.

Virus-Incorporated Biomimetic Nanocomposites for Tissue Regeneration

Owing to the astonishing properties of non-harmful viruses, tissue regeneration using virus-based biomimetic materials has been an emerging trend recently. The selective peptide expression and enrichment of the desired peptide on the surface, monodispersion, self-assembly, and ease of genetic and chemical modification properties have allowed viruses to take a long stride in biomedical applications. Researchers have published many reviews so far describing unusual properties of virus-based nanoparticles, phage display, modification, and possible biomedical applications, including biosensors, bioimaging, tissue regeneration, and drug delivery, however the integration of the virus into different biomaterials for the application of tissue regeneration is not yet discussed in detail. This review will focus on various morphologies of virus-incorporated biomimetic nanocomposites in tissue regeneration and highlight the progress, challenges, and future directions in this area.