Figure 2.

Dose-dependent effects of RTD-1 in LPS-induced alveolar macrophage inflammation in vitro. To assess the effects of RTD-1, cell culture supernatant from 24-hour 100 ng/ml LPS-induced MH-S alveolar macrophage cells (1.25 × 10⁵) in the presence or absence of 100 μg/ml RTD-1 was analyzed for soluble cytokines, macrophage inflammatory protein (MIP)-2 (A), keratinocyte-derived chemokine (KC) (B), monocyte chemoattractant protein (MCP)-1 (C), IL-6 (D), and TNF (E); n = 3 per group; mean (±SD). Treatment compared with control by unpaired two-sample t test. **P < 0.01, ***P < 0.001, ****P < 0.0001. In a separate investigation, supernatant from 24-hour–stimulated cells in the presence of 0, 0.1, 1, 10, and 100 μg/ml RTD-1 were analyzed for TNF dose response (F); n = 5 per group; mean (±SD). CI = confidence interval; IC₅₀ = half-maximal inhibitory concentration; NC = negative control.