A team at NTNU, Trondheim in Norway have shown that IONPs apparently inhibit LPS induced pro-inflammatory cytokine production.
In one experimental procedure they used confocal microscopy (combining fluorescence and transmission) to detect impact on the internalisation of LPS by nanoparticles, using DRAQ5 as the nuclear counterstain in monocytes.
One premise of this work is that co-stimulation of the normal human immune system is a common occurrence and therefore such observations should be of concern.
Grosse, S., Stenvik, J., & Nilsen, A. M. (2016).
Iron oxide nanoparticles modulate lipopolysaccharide-induced inflammatory responses in primary human monocytes.
International Journal of Nanomedicine, 11, 4625.