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Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
Published on: January 17, 2014
Initial Host Response to Bacteria in the Murine Lung Differs Between Pseudomonas aeruginosa, Staphylococcus aureus
Liselotte Preu1, Markus Bischoff2, Nils T Veith3
1Institute for Anatomy and Cell Biology, Saarland University, Kirrberger Strasse, 66421, Homburg, Saar, Germany.
Abstract:
Phagocytosis of bacteria is an important process during early host defence. It has been directly observed only ex vivo or in vitro. Here, we report on the observation of phagocytosis under in vivo conditions by using intravital microscopy in the murine lung. Suspensions of fluorescently labelled Streptococcus pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa cells were each instilled intratracheally to anaesthetized mice. After thoracotomy, the alveolar surface was observed for 30 min. Alveolar phagocytes exhibiting ingested bacteria could be detected and counted. The highest numbers were found after the infection with P. aeruginosa. By using intravital microscopy, cellular host defence could be observed in living mice lungs. The initial phagocytic reaction crucially depends on the species of applied bacteria invading the lung.
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