EN
The objective of this study was to determine the effect of a nonionic silver nanocolloid administered orally for 7 or 14 d at three concentration levels (25 ppm, 2.5 ppm, and 0.25 ppm) on the phagocytic activity and mitogenic response of splenocytes, and levels of selected cytokines in the serum of NMRI mice. The phagocytic activity of splenocytes was determined by respiratory burst activity and potential killing activity tests, mitogenic response was measured using the MTT assay, and serum levels of IL-lß, IL-6, IL-10, IL-12 p70, and TNF-α were determined by ELISA using commercially available reagents. Silver nanoparticles (Ag-NPs) administered at the lowest dose (0.25 ppm) for 7 d enhanced the respiratory burst activity and proliferative response of ConA- stimulated splenocytes. However, when administered for 14 d, low doses of Ag-NPs lowered both: the respiratory burst activity and the potential killing activity of splenocytes (0.25 ppm), elevated the levels of proinflammatory IL-6 and IL-12 (2.5 ppm and 0.25 ppm), and had a beneficial effect only on the proliferation of LPS-stimulated cells (2.5 ppm). Prolonged administration of Ag-NPs was found to have a detrimental effect on healthy organisms, thus necessitating caution in the use of dietary supplements containing silver nanoparticles.