IL-17RA exacerbates NP inflammation and tissue pathology during IAV.

WT C57BL/6 and IL17RA^-/- (KO) mice were i.n. inoculated with 10 μl PBS containing 50xTCID₅₀ of PR8. Mice were euthanized at 3, 7, and 14 dpi for histological analysis of nasopharyngeal inflammation. A-B. H&E stain of mouse nasal septa and inflammatory scores. Black arrow: leukocytic infiltration. Scale bar: 50 μm. C. Viral titer present in nasal lavage determined by TCID₅₀. Data were representative of one experiment (n = 3) and expressed as SEM. Data were analyzed by One-Way ANOVA with Tukey’s post-hoc in B and C. *p<0.05, **p<0.01, ***p<0.001.