Host Responses to Biomaterials

Porous-based biomaterials for tissue engineering and drug delivery applications

Surface modification of polymers by plasma treatments for the enhancement of biocompatibility and controlled drug release

Surfaces play an important role in a biological system for most biological reactions occurring at surfaces and interfaces. The development of biomaterials for tissue engineering is to create perfect surfaces which can provoke specific cellular responses and direct new tissue regeneration. The improvement in biocompatibility of biomaterials for tissue engineering by directed surface modification is an important contribution to biomaterials development. Among many biomaterials used for tissue engineering, polyesters have been well documented for their excellent biodegradability, biocompatibility and nontoxicity. However, poor hydrophilicity and the lack of natural recognition sites on the surface of polyesters have greatly limited their further application in the tissue engineering field. Therefore, how to introduce functional groups or molecules to polyester surfaces, which ideally adjust cell/tissue biological functions, becomes more and more important. In this review, recent advances in polyester surface modification and their applications are reviewed. The development of new technologies or methods used to modify polyester surfaces for developing their biocompatibility is introduced. The results of polyester surface modifications by surface morphological modification, surface chemical group/charge modification, surface biomacromolecule modification and so on are reported in detail. Modified surface properties of polyesters directly related to in vitro/vivo biological performances are presented as well, such as protein adsorption, cell attachment and growth and tissue response. Lastly, the prospect of polyester surface modification is discussed, especially the current conception of biomimetic and molecular recognition.

All biomaterials, when implanted in vivo, elicit cellular and tissue responses. These responses include the inflammatory and wound healing responses, foreign body reactions, and fibrous encapsulation of the implanted materials. Macrophages are myeloid immune cells that are tactically situated throughout the tissues, where they ingest and degrade dead cells and foreign materials in addition to orchestrating inflammatory processes. Macrophages and their fused morphologic variants, the multinucleated giant cells, which include the foreign body giant cells (FBGCs) are the dominant early responders to biomaterial implantation and remain at biomaterial-tissue interfaces for the lifetime of the device. An essential aspect of macrophage function in the body is to mediate degradation of bio-resorbable materials including bone through extracellular degradation and phagocytosis. Biomaterial surface properties play a crucial role in modulating the foreign body reaction in the first couple of weeks following implantation. The foreign body reaction may impact biocompatibility of implantation devices and may considerably impact short- and long-term success in tissue engineering and regenerative medicine, necessitating a clear understanding of the foreign body reaction to different implantation materials. The focus of this review article is on the interactions of macrophages and foreign body giant cells with biomaterial surfaces, and the physical, chemical and morphological characteristics of biomaterial surfaces that play a role in regulating the foreign body response. Events in the foreign body response include protein adsorption, adhesion of monocytes/macrophages, fusion to form FBGCs, and the consequent modification of the biomaterial surface. The effect of physico-chemical cues on macrophages is not well known and there is a complex interplay between biomaterial properties and those that result from interactions with the local environment. By having a better understanding of the role of macrophages in the tissue healing processes, especially in events that follow biomaterial implantation, we can design novel biomaterials-based tissue-engineered constructs that elicit a favorable immune response upon implantation and perform for their intended applications.

Tissue engineering is an emerging field of research which combines the use of cell-seeded biomaterials both in vitro and/or in vivo with the aim of promoting new tissue formation or regeneration. In this context, how cells colonize and interact with the biomaterial is critical in order to get a functional tissue engineering product. Cell-biomaterial interaction is referred to here as the phenomenon involved in adherent cells attachment to the biomaterial surface, and their related cell functions such as growth, differentiation, migration or apoptosis. This process is inherently complex in nature involving many physico-chemical events which take place at different scales ranging from molecular to cell body (organelle) levels. Moreover, it has been demonstrated that the mechanical environment at the cell-biomaterial location may play an important role in the subsequent cell function, which remains to be elucidated. In this paper, the state-of-the-art research in the physics and mechanics of cell-biomaterial interaction is reviewed with an emphasis on focal adhesions. The paper is focused on the different models developed at different scales available to simulate certain features of cell-biomaterial interaction. A proper understanding of cell-biomaterial interaction, as well as the development of predictive models in this sense, may add some light in tissue engineering and regenerative medicine fields.

Collagen, the primary structural protein in the extracellular matrix, has gained significant attention as a surface modification agent for biomaterials due to its exceptional biocompatibility, bioactivity, and ability to promote cellular adhesion and proliferation. Collagen coatings enhance the integration of synthetic and natural biomaterials with biological tissues, making them highly relevant in biomedical engineering, regenerative medicine, and implantable medical devices. This review explores the mechanisms by which collagen coatings improve biomaterial properties, including their role in modulating surface chemistry, hydrophilicity, and cellular interactions. Furthermore, we discuss various coating techniques, such as adsorption, covalent binding, and electrospinning, and their implications for optimizing material performance in biomedical applications. The advantages of collagen coatings in orthopedic, dental, and cardiovascular implants, as well as wound healing and drug delivery systems, are also examined. By highlighting the potential of collagen-functionalized surfaces, this article provides insight into the future directions of biomaterial innovation aimed at improving patient outcomes and medical device efficacy.

This review will present the latest research related to the production and application of spider silk and silk-based materials in reconstructive and regenerative medicine and tissue engineering, with a focus on musculoskeletal tissues, and including skin regeneration and tissue repair of bone and cartilage, ligaments, muscle tissue, peripheral nerves, and artificial blood vessels. Natural spider silk synthesis is reviewed, and the further recombinant production of spider silk proteins. Research insights into possible spider silk structures, like fibers (1D), coatings (2D), and 3D constructs, including porous structures, hydrogels, and organ-on-chip designs, have been reviewed considering a design of bioactive materials for smart medical implants and drug delivery systems. Silk is one of the toughest natural materials, with high strain at failure and mechanical strength. Novel biomaterials with silk fibroin can mimic the tissue structure and promote regeneration and new tissue growth. Silk proteins are important in designing tissue-on-chip or organ-on-chip technologies and micro devices for the precise engineering of artificial tissues and organs, disease modeling, and the further selection of adequate medical treatments. Recent research indicates that silk (films, hydrogels, capsules, or liposomes coated with silk proteins) has the potential to provide controlled drug release at the target destination. However, even with clear advantages, there are still challenges that need further research, including clinical trials.

This paper summarized the application of main artificial biomaterials and tissue engineering on repair of exercise-induced wrist ligament injury, on the basis of analysis about artificial biomaterial intervention of wrist ligament injury. At present, the anatomical, histological and biomechanical properties of wrist ligament has been studied in the domestic and foreign research; however, the studies about the application of artificial biomaterials and tissue engineering technology in the repair or reconstruction of exercise-induced Wrist ligament injury were very rare. With the development and progress of cell biology and molecular biology methods and technology, the research of ligament injury repair has entered a new stage, the new development of artificial biomaterials and tissue engineering provide a new direction for the Treatment and rehabilitation of exercise-induced wrist ligament injury.

Biomimetic is the study of various principles of working mechanisms of naturally occurring phenomena and their further respective integrations in to such a modified advanced mechanized instruments/models of digital or artificial intelligence protocols. Hence, biomimetic has been proposed in last decades for betterment of human mankind for improving security systems by developing various convenient robotic vehicles and devices inspired by natural working phenomenon of plants, animals, birds and insects based on biochemical engineering and nanotechnology. Hence, biomimetic will be considered next generation technology to develop various robotic products in the fields of chemistry, medicine, material sciences, regenerative medicine and tissue engineering medicine, biomedical engineering to treat various diseases and congenital disorders. The characteristics of tissue engineered scaffolds are found to possess multifunctional cellular properties like biocompatibility, biodegradability and favorable mechanized properties when comes in close contact with the body fluids in vivo. This chapter will provide overall overview to the readers for the study based on reported data of developed biomimetic materials and tools exploited for various biomedical applications and tissue engineering applications which further helpful to meet the needs of the medicine and health care industries.

Chapter 2 - Synthetic polymeric biomaterials for tissue engineering

Cell-instructive biomaterials are an essential component in tissue engineering and regenerative medicine. In the past three decades since the term “Tissue Engineering” was coined, researchers have made significant progress towards regenerating disease or damage tissues and organs by combining innovations in biomaterials, signaling molecules and cell therapies. However, challenges persist including limitations in properties of cell-instructive biomaterials, lack of advanced manufacturing technologies for precise spatiotemporal control of key players in tissue engineering, and hurdles in clinical translation and regulatory process. In this perspective article, we briefly review the current state of the field including the evolution in our understanding of the role biomaterial mechanics and scaffolding architecture, development of self-healing and modular biomaterials, and progress in advanced manufacturing technologies such as 3D bioprinting. In addition, we discuss about how innovation in research technologies including multi-omics and spatial biology, and advanced imaging modalities may pave the way for enhancing our understanding about cell-biomaterial interactions. Finally, we present our perspective as early career clinicians and researchers on the key role and potential impact that clinician-scientists can generate in the development, validation, clinical translation and adoption of the next-generation of cell-instructive biomaterials for application in engineering tissues and organs to impact human health.

A review of bio-based dialdehyde polysaccharides as multifunctional building blocks for biomedical and food science applications.

The rising costs and aging of the population due to a low birth rate negatively affect the healthcare system in Japan. In 2011, the Council for Science and Technology Policy released the 4th Japan’s Science and Technology Basic Policy Report from 2011 to 2015. This report includes two major innovations, ‘Life Innovation’ and ‘Green Innovation’, to promote economic growth. Biomedical engineering research is part of ‘Life Innovation’ and its outcomes are required to maintain people’s mental and physical health. It has already resulted in numerous biomedical products, and new ones should be developed using nanotechnology-based concepts. The combination of accumulated knowledge and experience, and ‘nanoarchitechtonics’ will result in novel, well-designed functional biomaterials.This focus issue contains three reviews and 19 original papers on various biomedical opics, including biomaterials, drug-delivery systems, tissue engineering and diagnostics. We hope that it demonstrates the importance of collaboration among scientists, engineers and clinicians, and will contribute to the further development of biomedical engineering.

Background: Nanotechnology has revolutionized fields like medicine and biotechnology by enabling the manipulation of materials at the atomic level. Gold nanoparticles (AuNPs) are particularly valued for their unique optical and chemical properties, making them ideal for biomedical applications. Hydrogels, known for their biocompatibility and water retention capabilities, are key materials in biomedical engineering. This study explores the synthesis and characterization of peptide-gold nanoparticle hybrid hydrogels, combining the benefits of AuNPs and peptide-based hydrogels for potential biomedical applications. Methods: Peptides were synthesized using solid-phase peptide synthesis (SPPS) and characterized through high-performance liquid chromatography (HPLC) and mass spectrometry. Gold nanoparticles were produced via the citrate reduction method and functionalized with peptides through Au–S bonds. These functionalized peptides self-assembled into hydrogels, which were then analyzed using transmission electron microscopy (TEM), UV-Vis spectroscopy, and dynamic mechanical analysis (DMA) to evaluate their structural, optical, and mechanical properties. Results: The peptides showed high purity and accurate molecular weights. AuNPs were successfully synthesized and uniformly dispersed within the hydrogel matrix. TEM and cryo-TEM imaging confirmed nanoparticle incorporation, and rheological analysis demonstrated enhanced mechanical strength and shear-thinning behavior in the hybrid hydrogels. Conclusion: The developed peptide-gold nanoparticle hybrid hydrogels show great potential as multifunctional biomaterials, suitable for various biomedical applications such as drug delivery and tissue engineering.

The second edition of this popular introductory undergraduate textbook uses examples, applications, and profiles of biomedical engineers to show students the relevance of the theory and how it can be used to solve real problems in human medicine. The essential molecular biology, cellular biology, and human physiology background is included for students to understand the context in which biomedical engineers work. Updates throughout highlight important advances made over recent years, including iPS cells, microRNA, nanomedicine, imaging technology, biosensors, and drug delivery systems, giving students a modern description of the various subfields of biomedical engineering. Over two hundred quantitative and qualitative exercises, many new to this edition, help consolidate learning, whilst a solutions manual, password-protected for instructors, is available online. Finally, students can enjoy an expanded set of leader profiles in biomedical engineering within the book, showcasing the broad range of career paths open to students who make biomedical engineering their calling.