Humoral immune responses to S-layer-like proteins of Bacteroides forsythus.
Bacteroides forsythus is one of the important periodontopathic bacteria, and this microorganism is known to have an S-layer outside the outer membrane. The S-layer-like antigens were recently isolated from B. forsythus, and they were found to be 270- and 230-kDa proteins in the envelope fraction. In this study, these proteins were confirmed to be specific to B. forsythus by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and they were clearly recognized by sera from patients with adult and early-onset periodontitis in Western immmunoblot analysis. We compared the immunoglobulin G (IgG) responses against the purified S-layer-like antigen by enzyme-linked immunosorbent assay. IgG responses against this antigen were low in healthy control subjects, but they were significantly higher in subjects with adult and early-onset periodontitis. Together with the fact that the IgG responses against the crude extract of B. forsythus did not rise significantly in patients with periodontitis, S-layer-like proteins are considered to be specific antigens of B. forsythus and may play an important role in the progression of periodontitis.
Section of Periodontology, Department of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Japan. yoneda@dent.kyushu-u.ac.jp
Masahiro
M
Yoneda
Takao
T
Hirofuji
Noriko
N
Motooka
Koji
K
Nozoe
Kayoko
K
Shigenaga
Hisashi
H
Anan
Mayumi
M
Miura
Hiroaki
H
Kabashima
Akiko
A
Matsumoto
Katsumasa
K
Maeda
D000328:Adult; D017668:Age of Onset; D000917:Antibody Formation; D000942:Antigens, Bacterial / Q000302:isolation & purification; D001426:Bacterial Proteins / Q000276:immunology* / Q000302:isolation & purification; D001439:Bacteroides / Q000737:chemistry / Q000276:immunology*; D015153:Blotting, Western; D016022:Case-Control Studies; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis; D008297:Male; D008565:Membrane Proteins / Q000276:immunology*; D008875:Middle Aged; D010518:Periodontitis / Q000276:immunology*
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D007106:Immune Sera; D007074:Immunoglobulin G; D008565:Membrane Proteins