Functional rewiring across spinal injuries via biomimetic nanofiber scaffolds

The regrowth of severed axons is fundamental to reestablish motor control after spinal-cord injury (SCI). Ongoing efforts to promote axonal regeneration after SCI have involved multiple strategies that have been only partially successful. Our study introduces an artificial carbon-nanotube based scaffold that, once implanted in SCI rats, improves motor function recovery. Confocal microscopy analysis plus fiber tracking by magnetic resonance imaging and neurotracer labeling of long-distance corticospinal axons suggest that recovery might be partly attributable to successful crossing of the lesion site by regenerating fibers. Since manipulating SCI microenvironment properties, such as mechanical and electrical ones, may promote biological responses, we propose this artificial scaffold as a prototype to exploit the physics governing spinal regenerative plasticity

Guiding Ethical Principles in Engineering Biology Research

Engineering biology is being applied toward solving or mitigating some of the greatest challenges facing society. As with many other rapidly advancing technologies, the development of these powerful tools must be considered in the context of ethical uses for personal, societal, and/or environmental advancement. Researchers have a responsibility to consider the diverse outcomes that may result from the knowledge and innovation they contribute to the field. Together, we developed a Statement of Ethics in Engineering Biology Research to guide researchers as they incorporate the consideration of long-term ethical implications of their work into every phase of the research lifecycle. Herein, we present and contextualize this Statement of Ethics and its six guiding principles. Our goal is to facilitate ongoing reflection and collaboration among technical researchers, social scientists, policy makers, and other stakeholders to support best outcomes in engineering biology innovation and development

Building Biocompatible Hydrogels for Tissue Engineering of the Brain and Spinal Cord

Tissue engineering strategies employing biomaterials have made great progress in the last few decades. However, the tissues of the brain and spinal cord pose unique challenges due to a separate immune system and their nature as soft tissue. Because of this, neural tissue engineering for the brain and spinal cord may require re-establishing biocompatibility and functionality of biomaterials that have previously been successful for tissue engineering in the body. The goal of this review is to briefly describe the distinctive properties of the central nervous system, specifically the neuroimmune response, and to describe the factors which contribute to building polymer hydrogels compatible with this tissue. These factors include polymer chemistry, polymerization and degradation, and the physical and mechanical properties of the hydrogel. By understanding the necessities in making hydrogels biocompatible with tissue of the brain and spinal cord, tissue engineers can then functionalize these materials for repairing and replacing tissue in the central nervous system

Hydrogel formulation determines cell fate of fetal and adult neural progenitor cells

Hydrogels provide a unique tool for neural tissue engineering. These materials can be customized for certain functions, i.e. to provide cell/drug delivery or act as a physical scaffold. Unfortunately, hydrogel complexities can negatively impact their biocompatibility, resulting in unintended consequences. These adverse effects may be combated with a better understanding of hydrogel chemical, physical, and mechanical properties, and how these properties affect encapsulated neural cells. We defined the polymerization and degradation rates and compressive moduli of 25 hydrogels formulated from different concentrations of hyaluronic acid (HA) and poly(ethylene glycol) (PEG). Changes in compressive modulus were driven primarily by the HA concentration. The in vitro biocompatibility of fetal-derived (fNPC) and adult-derived (aNPC) neural progenitor cells was dependent on hydrogel formulation. Acute survival of fNPC benefited from hydrogel encapsulation. NPC differentiation was divergent: fNPC differentiated into mostly glial cells, compared with neuronal differentiation of aNPC. Differentiation was influenced in part by the hydrogel mechanical properties. This study indicates that there can be a wide range of HA and PEG hydrogels compatible with NPC. Additionally, this is the first study comparing hydrogel encapsulation of NPC derived from different aged sources, with data suggesting that fNPC and aNPC respond dissimilarly within the same hydrogel formulation

Addressing the climate crisis through engineering biology

As the climate crisis deepens and the impacts are felt more often and more acutely worldwide, scientific, engineering, and policy communities need more tools and opportunities to make a difference in tackling climate challenges. The Engineering Biology Research Consortium (EBRC) has recently published a technical research roadmap, Engineering Biology for Climate & Sustainability, that describes and details short-, medium-, and long-term milestones for engineering biology tool and technology advancements that can be applied to mitigate, prevent, and adapt to climate change. These ambitious technical achievements can only be realized in the context of complementary research, policy, and investment and in combination with efforts from many other disciplines and approaches. Herein we illustrate the opportunities, as described by the roadmap, in engineering biology research and development to impact climate change and long-term environmental sustainability, and why and how engineering biology and subsequent biotechnologies should be among the most prominent of approaches to overcoming the climate crisis

Nanostructures to Engineer 3D Neural-Interfaces: Directing Axonal Navigation toward Successful Bridging of Spinal Segments

Neural interfaces are the core of prosthetic devices, such as implantable stimulating electrodes or brain–machine interfaces, and are increasingly designed for assisting rehabilitation and for promoting neural plasticity. Thus, beyond the classical neuroprosthetic concept of stimulating and/or recording devices, modern technology is pursuing toward ideal bio/electrode interfaces with improved adaptability to the brain tissue. Advances in material research are crucial in these efforts and new developments are drawing from engineering and neural interface technologies. Here, a microporous, self‐standing, 3D interface made of polydimethylsiloxane (PDMS) implemented at the interfacing surfaces with novel conductive nanotopographies (carbon nanotubes) is exploited. The scaffold porosity is characterized by 3D X‐ray microtomography. These structures are used to interface axons regenerated from cultured spinal explants and it is shown that engineering PDMS 3D interfaces with carbon nanotubes effectively changes the efficacy of regenerating fibers to target and reconnect segregated explant pairs. An improved electrophysiological performance is shown when the spinal tissue is interfaced to PDMS enriched by carbon nanotubes that may favor the use of our substrates as regenerative interfaces. The materials are implanted in the rat brain and a limited tissue reaction surrounding the implants at 2, 4, and 8 weeks from surgery is reported

Making Security Viral: Shifting Engineering Biology Culture and Publishing.

The ability to construct, synthesize, and edit genes and genomes at scale and with speed enables, in synergy with other tools of engineering biology, breakthrough applications with far-reaching implications for society. As SARS-CoV-2 spread around the world in early spring of 2020, researchers rapidly mobilized, using these tools in the development of diagnostics, therapeutics, and vaccines for COVID-19. The sharing of knowledge was crucial to making rapid progress. Several publications described the use of reverse genetics for the de novo construction of SARS-CoV-2 in the laboratory, one in the form of a protocol. Given the demonstrable harm caused by the virus, the unequal distribution of mitigating vaccines and therapeutics, their unknown efficacy against variants, and the interest in this research by laboratories unaccustomed to working with highly transmissible pandemic pathogens, there are risks associated with such publications, particularly as protocols. We describe considerations and offer suggestions for enhancing security in the publication of synthetic biology research and techniques. We recommend: (1) that protocol manuscripts for the de novo synthesis of certain pathogenic viruses undergo a mandatory safety and security review; (2) that if published, such papers include descriptions of the discussions or review processes that occurred regarding security considerations in the main text; and (3) the development of a governance framework for the inclusion of basic security screening during the publication process of engineering biology/synthetic biology manuscripts to build and support a safe and secure research enterprise that is able to maximize its positive impacts and minimize any negative outcomes