[Biochemical analysis of lipopolysaccharides from respiratory pathogenic Branhamella catarrhalis strains and the role of anti-LPS antibodies in Branhamella respiratory infections].
We characterized lipopolysaccharides (LPSs) from respiratory pathogenic Branhamella catarrhalis (BC) strains, and evaluated the protective property of anti-BC LPS antibody in BC respiratory infections. LPSs from four strains of BC were lipooligosaccharide having no O-side chain and a M(r) of 3 KDa, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). All of them produced different patterns, showing two to four bands on SDS-PAGE. We found high level of anti-BC IgG antibody in convalescent sera from a patient with BC respiratory tract infection by ELISA. This IgG antibody recognized BC LPSs on Western blots. Two respiratory pathogens of BC (strains; 87-122, 88-23) were tested in a bactericidal assay employing a convalescent sera. 87-122 strain was susceptible to antibody-dependent, complement-mediated killing, while 88-23 strain was resistant. The killing of 87-122 strain was inhibited by addition of the homologous BC LPS to the convalescent sera in a dose-dependent manner. These data support that anti-BC LPS antibody may mediate complement-lysis of some strains of BC, and play a protective role in BC respiratory infections.
Tanaka
H
H
Department of Internal Medicine, Nagasaki University.
Oishi
K
K
Sonoda
F
F
Iwagaki
A
A
Nagatake
T
T
Matsumoto
K
K
D000907:Antibodies, Bacterial / Q000276:immunology*; D004586:Electrophoresis; D006801:Humans; D015151:Immunoblotting; D008070:Lipopolysaccharides / Q000032:analysis*; D001936:Moraxella catarrhalis / Q000737:chemistry* / Q000276:immunology; D016870:Neisseriaceae Infections / Q000276:immunology*; D012141:Respiratory Tract Infections / Q000276:immunology*
D000907:Antibodies, Bacterial; D008070:Lipopolysaccharides