title: Human immune response to nontypeable Haemophilus influenzae in chronic bronchitis.
abstract: Nontypeable Haemophilus influenzae (NTHI) causes recurrent respiratory tract infections in patients with chronic bronchitis. To elucidate the human immune response to NTHI, sera from 2 patients with exacerbations of chronic bronchitis due to NTHI were characterized. Both patients developed new bactericidal antibodies following infection. Immunoblot assays with homologous strains revealed antibodies to many antigens, with minimal difference between pre- and postexacerbation sera. By contrast, whole cell radioimmunoprecipitation, which detects antibodies exclusively to epitopes exposed on the bacterial surface, revealed that both patients made new antibodies to a limited number of antigens following infection, including P2, the major outer membrane protein of NTHI. Adsorption experiments showed that strain-specific, surface-exposed epitopes on the P2 molecule are targets for bactericidal antibodies. These results indicate that new bactericidal antibodies following infection by NTHI recognize antigenically heterogeneous surface-exposed epitopes on P2 and other surface proteins of NTHI.
authors.affiliation: Department of Medicine, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, and Department of Veterans Affairs Western New York Healthcare System, 14215, USA.
authors.forename: K
authors.initials: K
authors.lastname: Yi
authors.forename: S
authors.initials: S
authors.lastname: Sethi
authors.forename: T F
authors.initials: TF
authors.lastname: Murphy
mesh_terms: D000907:Antibodies, Bacterial / Q000276:immunology; D001991:Bronchitis / Q000276:immunology*; D002908:Chronic Disease; D006192:Haemophilus Infections / Q000276:immunology*; D006193:Haemophilus influenzae / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting
chemical_list: D000907:Antibodies, Bacterial