a, Experimental scheme for (b): “ABX” = MNVA in drinking water; “MT” = microbiota transfer; “Kp” = K. pneumoniae intranasal inoculation; and “Sample” = upper airway lavage sampling; “Dexa” = dexamethasone treatment. Days relative to K. pneumoniae inoculation. Upper airway cytokine levels in adult mice inoculated with K. pneumoniae (WT B5055), unencapsulated K. pneumoniae (∆CPS B5055), and complemented K. pneumoniae (∆CPS::CPS B5055) (n=5,7 animals). Horizontal lines indicate median values, error bars are standard deviation. (c) Upper airway commensal levels in adult mice on the final day of dexamethasone administration (n=5 animals). Statistical comparisons were made Kruskal–Wallis test with Dunn’s correction for multiple comparisons. Horizontal lines indicate median values.