RESPONSE OF GUINEA-PIGS TO A VACCINE CONTAINING A NEW ADJUVANT (SAF) AND GRAM-NEGATIVE BACTERIA

Porphyromonas gingivalis is a gram-negative pathogen associated with s evere periodontitis in man and other animals, A vaccine against P. gin givalis infection may improve resistance to such infection and disease progression in susceptible individuals, A vaccine composed of formali n-killed P. gingivalis and Syntex adjuvant formulation or saline was t ested in guinea pigs. Blood was drawn before and at 2, 4, 6, 8, 24, an d 27 weeks after immunization, There was no morbidity or mortality as a result of vaccination, and necropsy revealed no organ abnormalities or residual injection site granulomas, Serum immunoglobulin G (IgG) an tibody titer and avidity were measured by enzyme-linked immunosorbent assay, and Western blots were done to determine the immunodominant ant igens. The IgG titer increased more rapidly and reached higher values in the ani mals receiving SAF plus P. gingivalis vaccine than in those receiving saline plus P. gingivalis. Antibody titer decreased by 27 w eeks, but avidity was twofold greater at 27 than at 8 weeks. Western b lots indicated that protein and carbohydrate antigens are recognized.