Pseudomonas aeruginosa infection and bactericidal permeability increasing protein (BPI) autoimmunity in cystic fibrosis patients

Bactericidal permeability increasing protein (BPI) is an important antimicrobial protein used in the human immune response against gram-negative bacteria. An autoimmune response against BPI in cystic fibrosis (CF) patients is associated with worsening disease progression. This study investigates the relationship between presence of anti-BPI autoantibodies and infection by the gram-negative bacterium Pseudomonas aeruginosa in CF patients. P. aeruginosa and BPI reactivity of sera samples were measured by ELISA and Western blot. The results of the current study support an association between expression of antibodies to BPI and expression of antibodies to P. aeruginosa. Autoreactivity to BPI can serve as a possible marker of disease progression and a potential therapeutic target in cystic fibrosis patients.