4.6. Data Analysis

For the screening assay, the concentration of cytokines in the supernatants of cells treated with abietane derivatives was reported, as well as the percentage of inhibition (based on the concentration of the vehicle-treated and LPS-stimulated control). Those compounds that inhibited cytokine production below the cut-off level (mean-2SD of the LPS-stimulated control, based on more than 20 replicate wells collected from more than 7 experiments) were considered significant inhibitors. For the dose–response experiments, results (cytokine concentration, percentage of CD40+ and CD86+ cells and MFI) were reported as the mean ± SEM. Data collection and analysis, as well as ANOVA tests performed using the GraphPad PRISM 7.0 software (GraphPad Software Inc., San Diego, CA, USA).