Title: Predicting the Impact of Engineered Nanomaterials on Lung Diseases
Speaker: Dr. James C. Bonner
Department of Environmental & Molecular Toxicology,
North Carolina State University, Raleigh, NC
Date: February 27, 2014
Time: 12:30-1:30 pm
Place: 665 Huntington Ave, Building 1, Room 1302, Boston, MA 02115
Abstract: The nanotechnology revolution offers enormous societal and economic benefits for innovation in the fields of engineering, electronics, and medicine. Nevertheless, evidence from rodent inhalation studies show that biopersistent engineered nanomaterials, including carbon nanotubes and metal nanoparticles, have the potential to stimulate immune, inflammatory, or fibroproliferative responses in the lung and pleura. These data suggest possible risks for pulmonary fibrosis or the development of pleural disease as a consequence of occupational or consumer exposure. Some engineered nanomaterials also exacerbate pre-existing allergen-induced inflammation by altering the balance of distinct T-helper cell phenotypes, suggesting that they could serve as sensitizers or adjuvants to alter the innate immune response. These findings suggest that individuals with asthma or other pre-existing respiratory diseases would be particularly susceptible to the adverse health effects of nanomaterials. Due to their nanoscale dimensions and increased surface area per unit mass, engineered nanomaterials have a much greater potential to reach the distal regions of the lung, generate reactive oxygen species, and alter cell signaling pathways linked to disease pathogenesis. The goal of this presentation will be to discuss mechanisms through which engineered nanomaterials cause lung, airway, and pleural disease, especially in the context of susceptible individuals with pre-existing disease. Functionalization of nanomaterials through processes such as atomic layer deposition will also be discussed as a means of altering the pathogenicity of nanomaterials.
Protocol for the high throughput Comet Assay. (A) Assembly of macrowell comet array. Agarose gel with microwells is sandwiched between a glass substrate and a bottomless 96-well plate and sealed with mechanical force. Approximately 300 arrayed microwells comprise the bottom of each macrowell. (B) Preparation of the nanoparticle suspension according to the protocol by Cohen at al. (C) Protocol for exposing the cells to the nanoparticles. (D) Loading of the exposed cell samples in the macrowells and running the microwell assay.
Nanomaterials are part of daily life. Although there is a wide range of methods to evaluate their potential toxic effects, there is no way to evaluate gene damage.
Scientists at Harvard University in the School of Public Health in collaboration with the research Group of Bevin P. Engelward at MIT, have developed a screening assay to detect the genotoxic potential of nanomaterials. Metal oxide nanoparticles in biological systems can generate reactive oxygen species, which can overwhelm innate antioxidant defenses and cause oxidative stress. Oxidative stress, among other factors, has been associated with DNA damage and mutations, precursors to cancer. As more and more commercial products contain nanomaterials consisting of metal oxides such as titanium dioxide and zinc oxide, screening assays such as these are crucial to reducing potential health hazards. Christa Watson, postdoctoral research fellow at HSPH, suggests that accurate toxicity assessments of nanomaterials before they are incorporated into consumer products can help us prevent similar consequences that we are currently facing from asbestos exposures such as mesothelioma. Current efforts are ongoing to understand the novel toxicities nanomaterials may pose on public safety. This research was recently published in ACS Nano February 14, 2014 DOI: 10.1021/nn404871p
ZnO is a widely used material in cosmetics and food applications. The ions however, that are leaching have been linked to potential adverse effects. In our center we developed a safer formulation concept to mitigate toxicity by encapsulating the materials in a thin layer of Silica.
One of the main constituents of sunscreen is the ZnO particles. ZnO nanoparticles are sought out for UV-filter applications thanks to their inherent optoelectronic properties and are, therefore, broadly used today in cosmetics and polymers. Preliminary toxicological data, however, point out that they can induce significant DNA damage and genotoxicity due to their Zn2+ ion leaching. It has become important for the nanotechnology industry, to devise scalable, safer-by-design approaches to minimize the ZnO nanoparticle dissolution and toxicity without altering their desired optoelectronic properties.
G. Sotiriou the lead author of the paper.
In their work, the researchers demonstrated a safer-by-design approach for ZnO nanorods using a scalable flame aerosol process. This technology allows for controlled synthesis of high-purity ZnO nanorods with highly crystalline core and a nanothin amorphous silica shell that improves their biocompatibility. The as-prepared nanorods exhibit high transparency in the visible range, but strong absorption in the UV rendering them suitable for use in sunscreens and polymers. Furthermore, it is demonstrated that the hermetic silica coating does not alter the desired optoelectronic properties of the core ZnO nanorods while their DNA damage potential has been 3-fold decreased.
You can read more at the Chemistry World news article or, directly the paper.
Please join us for our next meeting of the Massachusetts chapter of the New England Nanotechnology Association (NENA) to hear about some new developments in nanotechnology and nanotoxicology.
We’ll enjoy a continental breakfast, spend a little time networking, and hear about these new developments and other topics of interest. There is no cost to attend, so please RSVP today. Thank you and we look forward to seeing you soon.
8:30 – 9:00AM: Networking and refreshments
9:00 – 9:10AM: Welcome and introductions - William S. Rogers, Jr., Esq., Partner, Prince Lobel Tye LLP, Boston, MA
9:10-9:20AM: Speaker - Eric S. Howard, Corporate and Outreach Manager, NSF Center for High-rate Nanomanufacturing, Northeastern University, Boston, MA
9:20-9:35AM: Speaker - Philip Demokritou, Ph. D., Assoc. Professor and Director, Center for Nanotechnology and Nanotoxicology, Harvard School of Public Health, Cambridge, MA
9:35-9:45AM: Speaker - Joseph Brain, Ph.D., Cecil K. and Philip Drinker Professor of Environmental Physiology, Department of Environmental Health, Harvard School of Public Health, Cambridge, MA
9:45-10:00: Networking and adjourn
Click here to RSVP – deadline is 2/21/14
Can’t make the event? Join our LinkedIn Discussion Page.
We must have a complete list of attendees two days prior to the event in order to arrange visitor passes. No one can get in without a visitor’s pass.
If you have any questions, please don’t hesitate to contact me.
William S. Rogers, Jr.
Prince Lobel Tye LLP