Dotting the Quantum I's - Engineered nanoparticle toxicity

BrooklynDodger(s): Quantum Dots are engineered nanoparticles, which might be really commentexotic compared to the run of the mill carcinogenic nano particles like diesel particulate matter, carbon black and titanium dioxide. Too bad this investigation didn't explore relative potency between QD's - unlikely to ever undergo an inhalation bioassay, much less present a study in people - with the already known species.


Toxicology and Applied Pharmacology
Volume 238, Issue 2, 15 July 2009, Pages 160-169

Nanoparticles up-regulate tumor necrosis factor-α and CXCL8 via reactive oxygen species and mitogen-activated protein kinase activation

References and further reading may be available for this article. To view references and further reading you must purchase this article.

Hye-Mi Lee^{a, b}, Dong-Min Shin^{a, b}, Hwan-Moon Song^c, Jae-Min Yuk^{a, b}, Zee-Won Lee^d, Sang-Hee Lee^e, Song Mei Hwang^f, Jin-Man Kim^f, Chang-Soo Lee^{c, ,} and Eun-Kyeong Jo^{a, b, g, ,}

^aDepartment of Microbiology, College of Medicine, Daejeon 301-747, South Korea

^bInfection Signaling Network Research Center, College of Medicine, Daejeon 301-747, South Korea

^cDepartment of Chemical Engineering, College of Engineering, Chungnam National University, Daejeon 305-764, South Korea

^dGlycomics Team, Korea Basic Science Institute, Daejeon 305-333, South Korea

^eMolecular Genomics Laboratory, Department of Biological Science, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, South Korea

^fDepartment of Pathology, College of Medicine, Daejeon 301-747, South Korea

^gResearch Institute for Medical Sciences, College of Medicine, Daejeon 301-747, South Korea

Abstract

Evaluating the toxicity of nanoparticles is an integral aspect of basic and applied sciences, because imaging applications using traditional organic fluorophores are limited by properties such as photobleaching, spectral overlaps, and operational difficulties. This study investigated the toxicity of nanoparticles and their biological mechanisms. We found that nanoparticles, quantum dots (QDs), considerably activated the production of tumor necrosis factor (TNF)-α and CXC-chemokine ligand (CXCL) 8 through reactive oxygen species (ROS)- and mitogen-activated protein kinases (MAPKs)-dependent mechanisms in human primary monocytes. Nanoparticles elicited a robust activation of intracellular ROS, phosphorylation of p47phox, and nicotinamide adenine dinucleotide phosphate oxidase activities. Blockade of ROS generation with antioxidants significantly abrogated the QD-mediated TNF-α and CXCL8 expression in monocytes. The induced ROS generation subsequently led to the activation of MAPKs, which were crucial for mRNA and protein expression of TNF-α and CXCL8. Furthermore, confocal and electron microscopy analyses showed that internalized QDs were trapped in cytoplasmic vesicles and compartmentalized inside lysosomes. Finally, several repeated intravenous injections of QDs caused an increase in neutrophil infiltration in the lung tissues in vivo. These results provide novel insights into the QD-mediated chemokine induction and inflammatory toxic responses in vitro and in vivo.