Exposure to bacterial PAMPs before RSV infection exacerbates innate inflammation and disease via IL-1α and TNF-α

(1) Intranasal exposure to bacterial PAMPs increases the expression of cytokine and chemokines, in particular (2) IL-1α and TNF-α. (3) The expression of cytokines and chemokines drives the recruitment of innate immune cells including neutrophils and inflammatory monocytes into the lung. (4) When mice are infected 12h later with RSV this further (5) promotes the expression of IL-1α and TNF-α in the lung. (6) resulting in exacerbated disease. Illustration made in Biorender.