Effect of anti-PcrV antibody in murine chronic airway pseudomonas aeruginosa infection model

¹ Second Dept of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan
² Dept of Anesthesia and Critical Care, University of California, San Francisco, California

^* To whom correspondence should be addressed. E-mail: kyana-ngs{at}umin.ac.jp.

	Abstract

Pseudomonas aeruginosa is one of the most important pathogens in patients with chronic airway conditions such as cystic fibrosis and diffuse panbronchiolitis. Type III secretion system-mediated virulence factors contribute to the lung damage in chronic P. aeruginosa infection. We evaluated the effects of anti-PcrV IgG, which blocks the type III secretion system, in a mouse model of chronic P. aeruginosa infection. On bacteriologic examination, anti-PcrV IgG showed no bactericidal effects. On BALF analysis, total cell number and neutrophil ratios in the anti-PcrV IgG-treated groups were lower than those in the control group. In addition, MIP-2, TNF-, and IL- concentrations in BALF were lower in the anti-PcrV IgG-treated groups when compared with controls. Plasma anti-PcrV IgG titer was elevated after administration of anti-PcrV IgG. Although plasma titer decreased gradually, sufficient concentration was maintained during the experimental period. These data suggest that anti-PcrV IgG reduces the inflammatory reaction caused by chronic P. aeruginosa respiratory infection and may be useful in treating respiratory diseases.