Fig. 7

Systemic blockade of interleukin-4 receptor alpha (IL-4Rα) reduces house dust mite (HDM)-mediated excessive viral load and a systemic cytokine storm following pandemic H1N1 (pH1N1) infection. Lung tissue and plasma were obtained on day 8 post-infection from pH1N1-infected mice a–c qPCR was performed on RNA from homogenized lung tissue to measure the number of viral copies (pooled from two independent experiments), and results were compared using two-tailed Student’s t-test. Plasma was used to measure protein levels of d–f IL-6 and g–i IP-10. Data were compared using the Mann–Whitney U test, and are expressed as mean ± SEM. Blue/pink: intranasal phosphate-buffered saline (PBS) (n = 10) / intranasal HDM (n = 9); green/orange: intranasal HDM followed by prophylactic strategy of IL-4Rα blockade (n = 13) / IgG (n = 12); black/red: intranasal HDM followed by therapeutic strategy of IL-4Rα blockade (n = 12) / IgG (n = 12). *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001; ns: not significant