Figure 1.

Assessment of BMDC viability using flow cytometry.

Notes: Frequencies of BMDCs in early apoptosis phase (left) or dead (right) following 16-hour incubation with 20 nm (gray) or 1,000 nm (black) PS particles compared with non-treated cells (white), stained for Annexin V and PI, and measured by flow cytometry. Concentrations of PS particles ranged from 5 to 100 μg/mL. Ann+ (positive control for apoptosis) was obtained by fixation of BMDCs with 1% formalin for 40 minutes. PI+ (positive control for cell death) was obtained by placing BMDCs for 30 minutes at −80°C. Bar graphs show mean ± SEM; ***P<0.001 (positive control versus no NP); n=4.

Abbreviations: Ann, annexin; BMDC, bone marrow–derived dendritic cell; LPS, lipopolysaccharide; NP, nanoparticle; PI, propidium iodide; PS, polystyrene; SEM, standard error of the mean.