Carbon nanoparticles can pass through immune cell membranes, say researchers
Researchers at the university’s School of Public Health and College of Engineering experimented with C60, a carbon fullerenes nanomaterial, and published their findings in Nanoscale (a journal of The Royal Society of Chemistry).
The research
Angela Violi lead her research team through an exploration of various ways the particles could enter living immune cells of mice. They worked with “a combination of classical biological, biophysical and newer computational techniques, using models [they] developed,” according to the University.
Prior published studies used scenarios where cells were blasted with particle clusters, which is apparently not typically how animals and people are exposed to carbon nanoparticles.
The team observed that the C60 particles got through the cell membranes without setting the usual response—engulf and discharge—in motion.
“Computational modeling of C60 interacting with lipid bilayers, representative of the cellular membrane, show that particles readily diffuse into biological membranes and find a thermodynamically stable equilibrium in an eccentric position within the bilayer," saysVioli, a U-M professor of mechanical engineering, chemical engineering, biomedical engineering, and macromolecular science and engineering.
She explains that "the surprising contribution of passive modes of cellular entry provides new avenues for toxicological research, as we still don't know exactly what are the mechanisms that cause this crossing."
Health risks
Just how nanoparticles disrupt immune function is coming further into focus with each study.
Cosmetics Design recently reported that “Researchers at Pacific Northwest National Laboratory observed that some nanoparticles diminish the function of macrophage immune cells while others cause cell death.”
And The University of Michigan study adds to concern that nanoparticles can infiltrate the body and disrupt normal function, whether through contact or inhalation.
"It's entirely possible that even tiny amounts of some nanomaterials could cause altered cellular signaling," affrims Martin Philbert, dean and professor of toxicology at the U-M School of Public Health, in a U-M item about the work.
Exposure to airborne ingredients is a growing area of research. An international team of scientists published findings last October about the dermal uptake of airborne phthalates. That study was fairly small, though the researchers from the US, Denmark, and Germany maintain that “dermal absorption directly from indoor air should be included as a contributory exposure pathway in risk assessments of low-molecular-weight phthalates.”
