Themed collection on immunological biomaterials: where materials meet the immune system in health and diseases

Krishnendu Roy

Dr Krishnendu Roy is the Robert A. Milton Chair Professor at The Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, where he also serves as Executive Director of the Marcus Center for Therapeutic Cell Characterization and Manufacturing and the Center for ImmunoEngineering. Dr Roy's research interests are in the areas of controlled drug and vaccine delivery, Immunoengineering and stem cell engineering. He is a Fellow of the American Institute for Medical and Biological Engineering (AIMBE) and Fellow of the Biomedical Engineering Society (BMES) and Young Investigator Awardee from both the Controlled Release Society and The Society for Biomaterials. Dr Roy serves as a member of the Editorial Boards of the Journal of Controlled Release and the European Journal of Pharmaceutics and Biopharmaceutics.

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Modern medicine is in the midst of a revolution. Our thinking about the underlying pathophysiology of human diseases and how we approach to solve them have changed tremendously in the past decade. We are beginning to discover and appreciate that the immune system is critically involved in keeping us healthy and manifesting almost all known human diseases. Whether it is a simple fever, a cough, a vaccination, or whether it is cancer, diabetes, fibrosis, autoimmune or cardiovascular diseases; our immune system and immune-homeostasis plays a fundamental role. Our knowledge of immunology and how cells, organs and systems physiology work together with the immune system have increased exponentially over the past decade. This has also brought much appreciation of immunological balance (i.e. immune-homeostasis) and potentially new ways of treating diseases by precisely modulating one’s immune system to restore this balance. We are now on the verge of transformative changes in curing and managing diseases like cancer, arthritis, trauma, multiple sclerosis, diabetes, lupus, HIV and others; by harnessing the power of immunology.

The involvement of materials sciences and engineering is not new to immunology. Materials scientists, chemical and biomedical engineers, chemists, and pharmaceutical scientists have worked on implant pathology and vaccine delivery for decades, trying to design better materials that either avoid or trigger the immune system and to better understand host–materials interactions. But, what is different now is the acceptance that materials science, materials chemistry and engineering are critical for understanding fundamental immunological processes including immunological signaling and homeostasis, modeling of complex diseases and their outcomes as well as for developing new tools for high throughput analysis and imaging, providing new strategies for precise and targeted immune-modulation, and improving our understanding of the immune system through systems immunology and synthetic biology. What has also changed is the deeper appreciation and increased understanding among biomaterials scientists that without precise control of the immune system, materials based interventions for human health are unlikely to succeed. Whether it is drug and vaccine delivery, imaging, or regenerative medicine and tissue engineering; the role of immune-homeostasis and immune modulation is absolutely fundamental to the success of materials in medicine.

It is in this backdrop that this collection of articles is being published as a themed collection. The hope is to reach a broad audience whose expertise lies beyond the realm of materials science and engineering; an audience that ideally also include clinicians, immunologists, computational scientists, modeling experts, bioengineers and others. It is this convergence of multiple experts that would allow us to advance this field and benefit human health. The collection is primarily focused to showcase the work of young and mid-career investigators; the tremendous opportunities in immunoengineering and immune-materials have garnered the imagination of the next generation of materials scientists and engineers. Together, we envision a day in the future when physicians can routinely and rapidly assess the immune-status of a patient, use it to predict immune function and disease state and use materials-driven tools and engineering approaches, such as those discussed here, to enhance and modulate the immune system to prevent and cure diseases.

This themed collection focuses on a wide range of topics, including design or modification of biomaterials to control inflammation, modulate innate and adaptive immune responses, deliver vaccines and immunotherapeutics, enhance or augment regeneration and healing, high-throughput analysis of materials–immune interactions, etc. A variety of material-types are discussed, e.g. glycomaterials, synthetic polymers, inorganic materials, biological molecules, composites, etc.

A series of reviews in this collection provides a broad understanding of how various types of materials interact with the immune system and how new materials design strategies can be employed to control and modulate that response. Restuccia et al. (DOI: 10.1039/c5tb01780g) provide a detailed review on the emerging field of carbohydrate materials for immunomodulation and immunotherapies. Recent advances in multivalent carbohydrate synthesis have enabled widespread use of these materials in a variety of immunological applications; both for controlling and manipulating innate and adaptive immunity. The review also underscores the importance of carbohydrate antigens for vaccine development, a less explored area in cancer and infectious disease treatment. Review articles by Pacelli et al. (DOI: 10.1039/c5tb01686j) and Kim et al. (DOI: 10.1039/c5tb01605c) provide a thorough understanding of how materials surface properties affect immune response and the state-of-the-art of various strategies to control that response. They discuss both synthetic and natural biomolecule modification of surfaces as well as the role of topographical features to control immune cell responses. Lavik and Szeto, in their article (DOI: 10.1039/c5tb01825k), focus on nanoparticle design to control their interaction with the innate immune system. Given that most nanoparticles are preferably administered intravenously and that most synthetic particles elicit acute, systemic immune activation, this review provides critical understanding on the design of particulate materials to control and reduce those adverse reactions. It will be interesting to study, as more knowledge is gained in these areas, how materials shapes (e.g. nano or microparticle versus macroscale surfaces of the same material) differentially interact with the immune system.

A series of excellent articles in this collection has focused on emerging areas of materials design to address challenging medical problems. Park et al. (DOI: 10.1039/c5tb01647a) report development of a self-assembled composite particle, designed based on the virulence factor of Porphyromonas gingivalis, to cleave and inactivate tumor necrosis factor alpha, a major pro-inflammatory molecule implicated in the pathogenesis of many inflammatory diseases. This unique strategy of understanding the fundamentals of immunological design from successfully evolved pathogens and then applying that knowledge to materials design is the essence of the revolution in immunological materials discussed earlier. Snook and colleagues (DOI: 10.1039/c5tb01623a) report the design of a unique peptide–inorganic composite particle for oral delivery of vaccines. Effective oral vaccines remain the holy grail of vaccine development and design of new materials to enable safe and efficient mucosal immune response through the oral route could have tremendous impact in modern medicine. Both Nguyen et al. (DOI: 10.1039/c5tb01553g) and Lee et al. (DOI: 10.1039/c5tb01693b) report unique strategies to control activation of innate immune cells, either to mitigate material-induced inflammation or to treat inflammatory diseases like arthritis. Both these strategies exemplify the emerging field of material-directed immune modulation to control and restore immune-homeostasis. Finally, Acharya et al. (DOI: 10.1039/c5tb01754h) report a high throughput system to rapidly assess material-driven innate immune reactions, specifically in the context of vaccine development. Given the myriads of possible material designs, such high throughput assays are critical for rapidly screening effective formulations before large scale in vivo studies.

We hope that this themed collection provides much intellectual stimulation not only to materials scientists and engineers but also to a broader group of researchers and clinicians; exciting them about the potential of immunological biomaterials in treating human disorders and also enabling them to contribute new ideas and innovations in this area.

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