Fig. 7
Caspase-1 and NLRP3 dependent cytokine gene expression and release in response to Saharan dust. Air-liquid interface co-cultures with either wild type, caspase (CASP)1−/−, or NLRP3−/− THP-1 cells were exposed to 31 µg/cm² SD for 24 h or to 260 ± 30 ng/cm² LPS for 21 h. The relative gene expressions of IL1B (A), IL6 (B), IL8 (C), and TNFA (D) as well as basolateral cytokine releases of IL-1β (E), IL-6 (F), IL-8 (G), and TNFα (H) were assessed by qRT-PCR and ELISA, respectively. The gene expression results were normalized to wild type control ALI cultures as well as to the reference genes ACTB and GAPDH. Fold changes were derived from the means of ΔΔCT values and standard deviations of ΔCT values. Depicted are mean values with standard deviations. Mixed-effects models with Šidák’s post hoc test were calculated based on the ΔCT values and absolute cytokine concentrations for qRT-PCR and ELISA data, respectively. N = 4 independent experiments were performed (Control and LPS: one biological replicate per genotype; SD: duplicates; Comparisons to the non-exposed controls of the respective genotype: *p ≤ 0.05; **p ≤ 0.01; Comparisons to equally exposed wild type co-cultures: #p ≤ 0.05; ##p ≤ 0.01) n.d.: not detected