IgG antibody subclass response to Porphyromonas gingivalis outer membrane antigens in gingivitis and adult periodontitis
This study examined the reactivity of the IgG subclass response to the outer membrane antigens of P. gingivalis in adult periodontitis patients and gingivitis patients. Investigators took serum samples from 20 adult periodontitis patients who had > 6 mm loss of attachment from the CEJ in eight or more sites with radiographic evidence of bone loss. They also took sera from age-and sex-matched patients. P gingivalis was cultured and the outer membrane was then isolated. The results of the immunoblots showed that the adult periodontitis group recognized significantly more antigens than the gingivitis group in all but the IgG4 subclass. The predominant antibody was IgG2, followed by IgG3, IgG1, and then IgG4. Both the gingivitis and the periodontitis groups showed the highest response in IgG2 antibody. Nine bands of molecular mass 104.5, 99.9, 90.7, 84.6,65.4, 61.2, 54.6, 46.8 and 25.8 kDa were recognized by the periodontitis group, whereas the gingivitis group recognized three antigens (27.2, 24.2, 11.1 kDa).The IgG3 response identified 14 antigens. All the antigens were recognized by the adult periodontitis group and none by the gingivitis group. The results of the present study demonstrated that the adult periodontitis group recognized significantly more antigens than the gingivitis group. [M.C.R.]
Plak, B., J.Vance, J. Dryer, P. Bird, E. Gemmell, R. Reinhardt, and G. Seymour, J Periodont, 66:363, 1995