Keshavan, SandeepTorres Andón, FernandoGallud, AudreyChen, WeiReinert, KnutTran, LangFadeel, Bengt2021-04-052021-04-052021Nanomaterials 2021, 11(4), 883; https://doi.org/10.3390/nano11040883http://hdl.handle.net/10347/25286Engineered nanomaterials are potentially very useful for a variety of applications, but studies are needed to ascertain whether these materials pose a risk to human health. Here, we studied three benchmark nanomaterials (Ag nanoparticles, TiO2 nanoparticles, and multi-walled carbon nanotubes, MWCNTs) procured from the nanomaterial repository at the Joint Research Centre of the European Commission. Having established a sub-lethal concentration of these materials using two human cell lines representative of the immune system and the lungs, respectively, we performed RNA sequencing of the macrophage-like cell line after exposure for 6, 12, and 24 h. Downstream analysis of the transcriptomics data revealed significant effects on chemokine signaling pathways. CCR2 was identified as the most significantly upregulated gene in MWCNT-exposed cells. Using multiplex assays to evaluate cytokine and chemokine secretion, we could show significant effects of MWCNTs on several chemokines, including CCL2, a ligand of CCR2. The results demonstrate the importance of evaluating sub-lethal concentrations of nanomaterials in relevant target cellsengCopyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/)Atribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/Multi-walled carbon nanotubesNanoparticlesChemokinesMacrophagesTranscriptomicsjournal article10.3390/nano110408832079-4991open access