Identification of Biomarkers for Multi-walled Carbon Nanotube Exposure in Mouse Macrophage Cells

Abstract

Carbon nanotubes (CNTs) have unique properties that make them ideal for applications like constructing medical devices and drug delivery. Human health consequences resulting from exposure to CNTs in a medical setting remain unclear. Thus far, studies aimed at determining the biocompatibility of CNTs have relied on traditional toxicological endpoints such as cell death. Such studies have not led to a definitive answer regarding specific biological effects or health consequences of exposure to sub-toxic doses of CNTs. One potential health consequence of exposure to CNTs is the activation of the innate immune system that could result in chronic inflammation and compromised immunity. In experiments performed to identify biomarkers for MWCNT exposure and to determine if such exposure activates an innate immune response, the levels cytokines/chemokines were determined after MWCNT treatment of mouse macrophage cells (RAW264.7). Increased extracellular levels of a subset of cytokines/chemokines were observed upon MWCNT treatment. This subset of induced cytokines/chemokines represent potential biomarkers for CNT exposure. Furthermore, MWCNT treatment did not lead to the induction of all cytokines/chemokines tested suggesting that exposure to MWCNTs results in the activation of specific pathways of the innate immune system and not general inflammation.