Spss 22.0 software package

For multiple comparisons two-way analysis of variance (ANOVA) was performed, with factors being genotype (Wild Type or Transgenic) and treatment (LPS, Saline or IL-1β). Data were not always normally distributed, and, in these cases, nonparametric tests were used (Kruskal–Wallis and post hoc pair-wise comparisons with Mann–Whitney U-test). Post hoc comparisons were performed with a level of significance set at p ≤ 0.05. For data that were normally distributed and homoscedastic, we used a standard parametric post-hoc test (Bonferroni’s test) and for those that were normally distributed, but non-homoscedastic, we performed non-parametric post-hoc comparisons (Games–Howell’s test). For two-group comparisons, data were analysed using Student-t test when they were normally distributed, and the Mann-Whitney test was run if data did not pass the assumptions for parametric analyses. Data are presented as mean ± standard error of the mean (SEM). Symbols in the graphs denote post-hoc tests. For correlation analyses, data from AD patients with and without infection were plotted separately and Pearson linear regression tests were run. Statistical analyses were carried out with the SPSS 22.0 software package (SPSS, Inc., Chicago, IL, USA).