Figure 5.

Cytokines secretion levels following exposure to NM-100 by suspension inoculation or aerosol: TNF-α (A), IL-6 (B), IL-8 (C) and IL-1β (D). LPS (100 ng/mL, 24 h of treatment) was used as positive control, while untreated cultures were included as negative control (CTRL). Data are means of three independent determinations (n_tests = 3) ± standard deviation. The symbols (*) (**) and (***) indicate p values < 0.05, < 0.01 and < 0.001 vs. the untreated (negative) control (CTRL), respectively. Abbreviations: ALI, air–liquid interface; IL-1β, interleukin-1beta; IL-6, interleukin-6; LPS, lipopolysaccharide; NM, nanomaterials; TNF-α, tumor necrosis factor alpha.