Cytokine expression of epithelial cells after infection with
C. burnetii. Amounts of mRNA specific for IL-1β, IL-6 and TNF-α 24 h after infection with NMI and NMII were measured by qPCR. The data were normalized based on the housekeeping gene GAPDH and the uninfected cell control. A randomisation test with a pair-wise reallocation was used to compare ΔCT (cycle threshold)-values from four independent experiments (*p ≤ 0.05; **p ≤ 0.01).