Development of high-sensitive periodontitis diagnosis method using biotinylated polysaccharide antigens

点击翻译按钮获取中文摘要

Periodontitis has been recently considered to be an infectious disease that is induced by several specific bacteria. In this study, we developed a rapid and specific method for measuring antibodies to periodontopathic bacteria. Serotype-specific polysaccharide antigens (SPAs) were extracted from whole cells of Actinobacillus actinomycetemcomitans by autoclaving and purified by chromatography. The purified SPAs were activated with cyanogen bromide and then treated with adipic acid dihydrazide. The preparations were coupled with biotin or bovine serum albumin (BSA) by the carbodiimide method. Enzyme-linked immunosorbent assay plates pretreated with avidin were allowed to react with biotinylated SPAs. Studies using rabbit anti-A.a.sera showed the assay utilizing avidin-biotin was very specific and sensitive. Antibodies to the antigens in 1 : 6,44 to 1 : 12,800 dilutions of human sera from subjects with periodontitis could be detected by using the assay. Subcutaneous immunization of rabbits with BSA-SPA induced high titers of serum anti-SPA antibodies, and these antibodies enhanced phagocytosis and killing of A.a.by human polymorphonuclear leukocytes. These findings suggest that proteinconjugated polysaccharide antigens may be useful for diagnosis of periodontal disease and elucidating an etiological role of the antigens in the induction of the infectious disease.