Imaging Nanomaterials-cell Membrane Interactions
PNNL researchers have developed technologies needed to image nanoparticle trafficking in cells, including single molecule imaging described here.
Nanoscale particles are shown to exert harmful effects on human health and some adverse effects have been linked to the surface properties of nanomaterials. However, the specific chemical and physical parameters that facilitate nanoparticle-cell interaction and elicit inflammatory and toxic responses have not been fully characterized. Little is known about the mechanisms that underlie the attachment and internalization of individual or nanoscale aggregates, as they are likely to be presented to cells in vivo.
Positively charged amorphous silica nanoparticles scroll along microvilli of alveolar type II epithelial cell, unraveling surface property-dependent
Using video-rate fluorescence imaging with single-molecule sensitivity, PNNL researchers have identified processes underlying the attachment and internalization of individual nanoparticles with well-defined properties by alveolar type II epithelial cells. This approach avoids the experimentally induced agglomeration of nanoparticles and delineates the processes that are likely to occur in vivo. Researchers have also identified specific transmembrane molecules that mediate the attachment and internalization of nanoparticles that carry positive surface charge. The studies identified relationships between nanomaterial properties and cellular interactions and pathways, unraveling mechanisms of nanoparticle toxicity or biocompatibility.
Publication:
Orr, G, DJ Panther, KJ Cassens, JL Phillips, BJ Tarasevich and JG Pounds. 2009. "Syndecan-1 Mediates the Coupling of Positively Charged Submicrometer Amorphous Silica Particles with Actin Filaments Across the Alveolar Epithelial Cell Membrane." Toxicology and Applied Pharmacology 236 (2).
Orr, G, DJ Panther, JL Phillips, BJ Tarasevich, A. Dohnalkova, D Hu, JG Teeguarden, JG Pounds. 2007. "Submicrometer and Nanoscale Inorganic Particles Exploit the Actin Machinery to be Propelled Along Microvilli-like Structures into Alveolar Cells." ACS Nano 1(5), 463-475.
Contact: Gayla Orr