Establishment and evaluation of a mouse model of pulmonary Pseudomonas aeruginosa infection by intratracheal instillation

Abstract

Objective To establish and validate a mouse model of pulmonary infection of Pseudomonas aeruginosa. Methods The models of pulmonary Pseudomonas aeruginosa infection was established in mice by intratracheal instillation of 50 μL (1×108 CFU/mL) Pseudomonas aeruginosa suspension delivered through orotracheal intubation under a transillumination lamp. At 7 d after the infection, the mice were sacrificed for counting the bacterial colonies in the lungs and for pathological evaluation. Results After intratracheal instillation of Pseudomonas aeruginosa, the mice showed a poor general condition and had positive findings of Pseudomonas aeruginosa in the lung tissues with significantly increased blood white blood cell and neutrophil counts compared with the control mice (P < 0.05); pathological examination revealed obvious pathological changes and inflammations in the lungs of the mice after the infection. In the control mice, no bacteria or pathological changes were detected in the lung tissue, and the white blood cell and neutrophil counts were normal without evidence of inflammatory responses. Conclusion We successfully established a mouse model of pulmonary Pseudomonas aeruginosa infection by delivering the pathogens through tracheal intubation. This model shows a good stability and allows convenient quantitative analysis.

Keywords

• pseudomonas aeruginosa
• pulmonary infections
• intratracheal intubation
• infection model