Figure 9. Lung inflammation in OVA-treated RV1B-infected MDA5−/− mice: histology and airways responsiveness.

MDA5−/− mice and their control mice were sensitized and challenged with OVA and then infected with RV1B. A. Twenty-four h after infection, lungs were fixed and stained with hematoxylin and eosin (original magnification, 100×). B. Twenty-four h after infection, lungs were digested by collagenase. The number of infiltrated neutrophils were counted. C. Total respiratory system resistance one day after infection was determined by plethysmography. D. Four days after infection, MDA5 null mice showed significantly reduced lung eosinophils. E. Total respiratory system resistance four days after infection. Data represent mean±SEM for 6 mice (*p<0.05, two-way ANOVA).