Figure 3

Differential cytotoxic effects of ZnO NPs on human immune cell subsets.a PBMC were treated with varying concentrations (0, 0.5, 1, 2.5, 5, and 10 mM) of 8-nm ZnO NPs for 24 h and viability of CD3⁺T cells, CD4⁺T cells, B cells, NK cells, and monocytes present in same PBMC cultures determined by monitoring PI uptake using flow cytometry. Data from three independent experiments are presented with error bars depicting standard error (SE).Asterisks denote statistically significant (p < 0.05) differences between CD3⁺T cells, B cells, NK cells, and monocytes at indicated NP concentrations as determined using a repeated measures ANOVA.b ZnO NP toxicity on purified human primary monocytes. Purified human peripheral blood CD14⁺monocytes were treated with varying concentrations of ZnO NPs (0.0625–1 mM), and viability assessed using the Alamar Blue cytotoxicity assay witherror bars representing SE, (n = 4). The IC₅₀was determined using nonlinear regression analysis