Figure 4.

Inflammatory mediator release in lung homogenates and BALF supernatants following single high dose exposure to TiO₂ NPs. Changes in MCP-1 (A, homogenates;E, BALF supernatants), MIP-2 (B, homogenates;F, BALF supernatants), TNF-α (C, homogenates) and IL-10, (D, homogenates) following inhalation (blue squares) or instillation (green circles) are graphed as percentage of controls. Values are group means ± SE (n = 5). ND, levels were below the limit of detection by ELISA (TNF-α and IL-10 ~15 pg/mL). *, significantly different from corresponding controls; Φ, significantly different between exposure methods (p < 0.05).