Skip to main content
. 2019 Aug 30;10:2073. doi: 10.3389/fimmu.2019.02073

Figure 1.

Figure 1

Evaluation of MNP toxicity, quantification of MNP uptake, and its subcellular location in NK-92MI cells. (A) Viability of NK-92MI cells after treatment with MNPs, as measured by the AlamarBlue fluorometric test. (B) Analysis by flow cytometry of the percentage of apoptotic or necrotic human NK-92MI cells after incubation with MNPs by Annexin V/PI staining. (Alive: Annexin V−/PI−; early apoptotic: Annexin V+/PI−; late apoptotic: Annexin V+/PI+ and necrotic: Annexin V−/PI+). (C) Quantification of the iron associated with the NK-92MI cells after incubation with the different MNPs, through ICP-OES. The results shown (mean ± SD) are representative of three independent experiments, *p < 0.05, ****p < 0.0001. (D) Representative images of the NK-92MI cells after treatment with APS-MNPs acquired by confocal microscopy [cell membrane (red), NPMs (gray), and nucleus (blue)] (scale = 10 μm). The orthogonal projections were composed using ImageJ software. (E) Representative images obtained by TEM depicting NK-92MI cells after treatment with MNPs. The upper panels offer an overall view of the cell, while the lower panels show cell regions in greater detail to better illustrate the interactions between MNPs and the cell membrane.