Figure 6.

MERS-CoV cytokine responses in Calu-3 cells

Calu-3 cells were infected with MERS-CoV strains and H5N1 at multiplicity of infection of 2 for 1 h at 37°C. Figure shows gene expression of TNFα (A), CXCL10 (B), interferon β (C), and interleukin 6 (D) at 6, 24, and 30 h post infection. Means and SEMs of the mRNA copies expressed per 10⁵ β-actin are shown. The concentration of the cytokine and chemokine in the culture supernatant collected at 30 h post infection were further examined using (E) ELISA and (F) cytometric bead array. The bar chart represents the means and SEMs of the detected protein concentrations. UD represents samples with undetectable concentration, or concentration of the target protein below the detection limit of the ELISA or cytometric bead array kit. p values for significant differences between human and dromedary MERS-CoV are shown. MERS-CoV=Middle East respiratory syndrome coronavirus. EMC=human MERS-CoV EMC. AH13=MERS-CoV Dromedary/Al-Hasa-KFU-HKU13/2013. NRCE-HKU270=MERS-CoV Dromedary/Egypt-NRCE-HKU270/2013. TNFα=tumour necrosis factor α. IL-6=interleukin 6. IFNβ=interferon β. SEM=standard error of the mean.