|Budget Amount *help
¥6,700,000 (Direct Cost: ¥6,700,000)
Fiscal Year 1986: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1985: ¥5,800,000 (Direct Cost: ¥5,800,000)
The purpose of this study was to investigate the susceptibility of Actinobacillus actinomycetemcomitans ( Aa ) <Y_4> to anti Aa antibody.
First, in vivo assay was carried. Experimental periodontitis in dog was established by removal of the alveolar bone and wire ligature around teeth. Each 0.3 ml of antibody, sham antibody or PBS was injected on buccal attached gingiva, or 5 <micro> l of each was dropped in periodontal pocket 4 times. Nothing was carried out in control sites, and 2 <micro> l Aa suspension, adjusted to the concentration of 1 x <10^(11)> Aa/ml, was dropped on all sites. After 4 hours, contents of each pocket was collected by crevicular washing and cultured anaerobically. Total colony forming unit ( CFU ) of Aa was calculated and PMN leukocytes was counted.
Next, we have examined how the antibody influenced on complement mediated bactericidal activity and phagocytic activity of dog PMN leukocyte in vitro.
The results were as follows;
The bactericidal activity and the activity of accelerating PMN leukocyte migration of the antibody was not recognized. But the significant reduction of Aa CFU was recognized when that was incubated with antibody, complement and PMN leukocytes, and not stirred up. When antibody was included in the incubation, PMN leukocytes tended to phagocytize Aa cells compared to antibody free culture. This suggests that the antibody, comlement and PMN leukocyte system was capable of aggregating or phagocytizing Aa, but not killing.