Figure 6

Aggravated disease outcome in CHIKV-infected IFNαR+/− mice. Three-weeks old IFNαR+/− female mice (n = 7 to 11 animals per group) were infected via footpad inoculation with 10⁶ PFU of CHIKV. Immediately, these mice were administered intraperitoneally with ~2 µg/ml (total IgG concentration) mice sera from CHIKV-infected mice (enhanced) or PBS (non-enhanced). Daily assessment of (a) viremia and (b) disease score were performed. Data are presented as mean ± SD by Mann-Whitney U test (**P = 0.0027, **P = 0.0011, ***P = 0.0009, ***P = 0.0005, **P = 0.0017 and *P = 0.0159 for 2, 3, 4, 5, 6 and 7 dpi viremia respectively; ⁺P = 0.0125, ⁺⁺⁺P < 0.0001, ⁺⁺P = 0.0015 and ⁺P = 0.0277 for 4, 5, 6 and 7 dpi viremia respectively; *P = 0.0109 and *P = 0.0306 for 10 and 11 dpi disease score respectively; ⁺⁺⁺P < 0.0001, ⁺⁺⁺P = 0.0006, ⁺P = 0.0109, ⁺P = 0.0277, ⁺P = 0.0031, ⁺P = 0.0095 and ⁺P = 0.0031 for 1, 6, 7, 8, 9, 10 and 11 dpi disease score respectively. (*) indicates significance comparing between CHIKV-infected IFNαR+/− (blue) and WT animals (black); (+) indicates significance comparing between IFNαR+/− mice infected under enhanced (red) and non-enhanced (blue) conditions.