Expression of β-Defensin-3 in Lungs of Immunocompetent Rats with Methicillin-Resistant Staphylococcus aureus Ventilator-Associated Pneumonia

Rat model of MRSA VAP was obtained by intrabronchially inoculating rats with 2 × 109 cfu MRSA after 4 h of protective mechanical ventilation. VAP was more severe than nonventilated pneumonia in terms of histopathologic and microbiologic criteria, especially systemic spread. This may be associated with the inhibited up-regulation of BD-3 expression by mechanical ventilation.