Multiparametric Profiling of Engineered Nanomaterials: Unmasking the Surface Coating Effect

Abstract

Despite considerable efforts, the properties that drive the cytotoxicity of engineered nanomaterials (ENMs) remain poorly understood. Here, the authors inverstigate a panel of 31 ENMs with different core chemistries and a variety of surface modifications using conventional in vitro assays coupled with omics-based approaches. Cytotoxicity screening and multiplex-based cytokine profiling reveals a good concordance between primary human monocyte-derived macrophages and the human monocyte-like cell line THP-1. Proteomics analysis following a low-dose exposure of cells suggests a nonspecific stress response to ENMs, while microarray-based profiling reveals significant changes in gene expression as a function of both surface modification and core chemistry. Pathway analysis highlights that the ENMs with cationic surfaces that are shown to elicit cytotoxicity downregulated DNA replication and cell cycle responses, while inflammatory responses are upregulated. These findings are validated using cell-based assays. Notably, certain small, PEGylated ENMs are found to be noncytotoxic yet they induce transcriptional responses reminiscent of viruses. In sum, using a multiparametric approach, it is shown that surface chemistry is a key determinant of cellular responses to ENMs. The data also reveal that cytotoxicity, determined by conventional in vitro assays, does not necessarily correlate with transcriptional effects of ENMs.

Profiling Non-Coding RNA Changes Associated with 16 Different Engineered Nanomaterials in a Mouse Airway Exposure Model

“…A lncRNA-gene co-expression network analyses based on Pearson’s correlation coefficient, R > 0.8 to at least 15 genes, identified a set of 242 lncRNAs, whose relative expression profiles separate the exposed mice into 4 categories of unexposed, low, medium, and high relative toxicities. This ranking is consistent with in vitro cytotoxicity of the same materials in human primary macrophages and a THP-1 cell line [ 15 ]. These 242 lncRNAs were upregulated relative to control exposures and were highly associated with genes involved in regulation of cell cycle, chromosomal organization, and DNA damage response ( Figure 4 , right panel), suggesting these are shared mechanisms that explain the relative cytotoxicity of these set of ENM.…”

“…All 16 engineered nanomaterials studied were provided by the FP7-NANOSOLUTIONS consortium. Their synthesis, functionalization, and characterization are extensively described elsewhere [ 6 , 14 , 15 ]. Following the NANOSOLUTIONS standard operating procedures provided for each material, endotoxin free water (HyClone, HyPure Cell Culture Grade Water, Thermo Scientific, Waltham, MA, USA) was used for all ENM dispersions in glass tubes.…”

Biomarkers of nanomaterials hazard from multi-layer data

“…Detailed information on the synthesis can be found in ref. 14 . Moreover, the Expanded Methods in the Suppl.…”

Copper oxide nanoparticles trigger macrophage cell death with misfolding of Cu/Zn superoxide dismutase 1 (SOD1)

“…Hufnagel et al [ 20 ] applied an RT-PCR based array spanning 95 genes and found that HMOX1 as well as HSPA1A (encoding heat shock 70 kDa protein 1, also known as HSP72) were both upregulated in A549 cells exposed to CuO NPs. It also deserves mentioning that we recently performed a transcriptomics study of THP-1 cells exposed to a panel of 31 nanomaterials including pristine CuO NPs at a low dose, corresponding to a maximum of 10–15% cell death (EC 10 ) for 24 h [ 83 ], and we found that the most upregulated gene in cells exposed to CuO NPs was HMOX1 encoding HO-1. Furthermore, 10 of the 20 most upregulated genes encoded different MTs.…”