Fig. 1

Methamphetamine inhibited immune cell viability and promoted apoptosis. a CCK-8 assay was used to assess Jurkat cell, NK-92 cell and THP-1 cell viability after treatment with different METH concentrations at 24 h. Data represent mean ± SEM from three to seven independent experiments. b–d Quantitative results of the apoptosis cell percentages. Annexin V-FITC/PI analysis was used to assess Jurkat cell (b), NK-92 cell (c) and THP-1 cell (d) apoptosis after treatment with different METH concentrations and different treatment times by flow cytometry. e Flow cytometry analysis unveiled the apoptosis rates of the NK-92 cells treated with 250 μM METH at 24 h. Cell apoptosis includes early (Q3) and late (Q2) apoptosis. Percentage of cell apoptosis = Q2 + Q3. Apoptosis rates are displayed as histograms. Each bar represents the mean ± SEM (*p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001, compared with 0 μM)