Novel murine respiratory inhalation model for long term persistence, adaptation and migration of Pseudomonas aeruginosa.

Chronic bacterial infections are a key feature of a variety of lung conditions. The opportunistic bacterium, Pseudomonas aeruginosa, is extremely skilled at both colonising and persisting in the airways of patients with lung damage. It has been suggested that the upper airways (including the paranasal sinuses and nasopharynx) play an important role as a silent reservoir of bacteria. Over time, P. aeruginosa can adapt to its niche, leading to increased resistance in the face of the immune system and intense therapy regimes. Here we describe a unique murine respiratory inhalation model of P. aeruginosa infection that establishes for at least 28 days. We present evidence for adaptation in vivo, in terms of phenotype and genotype, suggesting that there is persistence in the airways and that the upper respiratory tract is a key niche in establishment of infection. This novel model provides a unique platform for studying evolutionary dynamics and therapeutics.