Influenza infection results in neutrophil influx to the nasopharynx.

<p>Wildtype mice were infected as index mice with the listed agents. On day 14, mice were euthanized, and nasal lavage was performed with PBS. <b>A.</b> A 100 µl sample of each lavage was analyzed by flow cytometry to detect total numbers of neutrophils (Ly6G⁺, CD11b⁺). Each dot represents the percentage of total events that were neutrophils per mouse. Statistical significance was assessed using the Kruskal-Wallis test followed by Dunn's post-test, and * indicates <i>p</i><0.05, while ** denotes <i>p</i><0.01. <b>B.</b> Immunofluorescence image (representative). Ten microliter samples of nasal lavage fluid were spotted onto a glass slide, fixed, and stained with DAPI (blue) and antibodies against Ly6B (green) and type 23F pneumococcal capsule polysaccharide (red).