Abstract
Aim: We investigated monocyte and macrophage death and cytokine production induced by amorphous silica nanoparticles (SiO2-NPs) to clarify the role of defined serum corona proteins. Materials & methods: The cytotoxic proinflammatory effects of SiO2-NPs on human monocytes and macrophages were characterized in no serum, in fetal calf serum and in the presence of purified corona proteins. Results: In no serum and in fetal calf serum above approximately 75 µg/ml, SiO2-NPs lysed monocytes and macrophages by plasma membrane damage (necrosis). In fetal calf serum below approximately 75 µg/ml, SiO2-NPs triggered an endolysosomal acidification and caspase-1-dependent monocyte death (pyroptosis). The corona high-density lipoproteins:albumin ratio accounted for the features of the SiO2-NPs in serum. Discussion: Corona high-density lipoproteins are a major determinant of the differential cytotoxic action of SiO2-NPs on monocytes and macrophages.
Supplementary Material
Financial & competing interests disclosure
This work was supported by the European Community‘s Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 201031 NANOPHOTO, the University of Padova, Italy (Ex 60%, 2009–2013 and PRAT 2011) and the Italian Ministry of Research (FIRB 2011, RBAP114AMK RINAME). The Varian 400 SS-NMR spectrometer used was acquired by the University of Padova thanks to funding from the Fondazione CARIPARO (Progetti di Eccellenza ‘Nano-Mode’ 2010). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.
Acknowledgements
The authors thank the Centro Trasfusionale of the Hospital of Padua (ULSS 16) for providing buffy coats. The authors also thank F Rastrelli for assistance with the nuclear magnetic resonance spectra and K Leone for ATP assays.