An ex vivo human model for safety assessment of immunotoxicity of engineered nanomaterials

The unique physicochemical properties of nanomaterials (NM) and engineered nanomaterials (ENM) have pushed their use in many applications ranging from medicine to the food industry, textiles, and many more fields. Thus, human exposure to NM and ENM is growing by the day. However, the current toxicity tests do not reflect the special characteristics of ENM and are not developed for ENM risk assessment. Here we propose a high-throughput cell-based assay using human peripheral blood mononuclear cells (PBMCs) that can monitor the effects of NM and ENM on cytotoxicity and innate immunity. The proposed assay is fully automated and miniaturized, with excellent assay performance parameters (Z-score >0.5), amenable for large screening campaigns in industrial setting. Immunotoxicity data for ENM safety assessment are collected in dose-response format. At different states, multiparametric readouts for cytotoxicity, and innate immunity are conducted in a combinatorial method, avoiding ENM-induced bias by endotoxin contamination. Integrating this high-dimensional data, allows (i) holistic safety assessment of immunotoxicity effects caused by ENM, classifying safe and toxic ENM phenotypes, and (ii) to deconvolve mode of action of the ENM effect on the PBMCs. As added value the data obtained can be used to troubleshoot ENM or for a safe-by-design approach in product development.