Antibodies to Actinobacillus actinomycetemcomitans in a Korean population.

Previous studies demonstrated that serum antibodies to Actinobacillus actinomycetemcomitans strain Y4 are significantly elevated in sera from localized juvenile periodontitis (LJP) and postlocalized juvenile periodontitis (P-LJP) patients compared to normal controls in United States populations. This study examined the age of subjects in relation to the antibody levels to A. actinomycetemcomitans in a Korean population. Seven groups were investigated including sera from newborns, infants, children, periodontally normal puberty and adult groups and LJP and P-LJP groups. Antibody levels were determined by an enzyme-linked immunosorbent assay (ELISA) to A. actinomycetemcomitans strain SNUDC 10-1 (serotype C) isolated from a Korean LJP patient. In the healthy non-LJP and non-P-LJP subjects, IgG levels decreased from the newborn group to the 5-month-old group and then gradually increased through the adult group. The IgM levels in these groups continuously increased from birth until a plateau was reached in the 2- to 6-year group. Serum IgA levels to strain SNUDC 10-1 were too low to be measured by this assay.