YONEDA Masahiro KYUSHU UNIVERSITY DEPT.OF DENTISTRY,RESEARCH INSTRUCTOR, 歯学部, 助手 (10253460)
KABASHIMA Hiroaki KYUSHU UNIVERSITY DEPT.OF DENTISTRY,RESEARCH INSTRUCTOR, 歯学部, 助手 (20214504)
HAMACHI Takafumi KYUSHU UNIVERSITY DEPT.OF DENTISTRY,RESEARCH INSTRUCTOR, 歯学部, 助手 (80198811)
MAEDA Katsumasa KYUSHU UNIVERSITY DEPT.OF DENTISTRY,PROFESSOR, 歯学部, 教授 (00117243)
|Budget Amount *help
¥2,300,000 (Direct Cost : ¥2,300,000)
Fiscal Year 1998 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1997 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1996 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Porphyromonas gingivalis (P.gingivalis) has been implicated in the initiation and progression of periodontal disease. In this study, we examined the ability of P.gingivalis culture supernatant to alter the expression of human T cell surface proteins. As judged by flow cytometric analysis, the expression of CD4 was almost lost after the pretreatment with the culture supematant. The expression of CD8 and CD2 was also significantly reduced. Other surface proteins such as CD11a, CD18, CD3, TCR- alphabeta and TCR- gammadelta did not show significant decrease.
Interestingly, when the culture supernatant was activated by reducing agents, it remarkably cleaved not only CD4, CD8, CD2, but also CD11a, CD18, TCR-gammadelta However, CD3 and TCR- alphabeta were not cleaved by this treatment. On the other hand, the activity of the culture supernatant was abolished by the preincuvation with cysteine proteinase inhivitors. These results suggest that P.gingivalis releases some proteinase inhibitors. The
se results suggest that P.gingivalis releases some cysteine proteinases which cleave T cell surface proteins, and these cysteine proteinases may contribute to the pathogenesis of periodontal disease by impeding T cell activation and immunefunction.
We also examined the ability of Bacteroides forsythus (B.forsythus), which had similar proteinase to P.gingivalis, to alter the expression of human polymorphonuclear neutrophil (PMNs) surface antigen and function. The expression of LEA-i molecule, CR3 and bacteriocid alactivity of PMNs were significantly increased after the pretreatment with the B.forsythus sonicated extract (B.forsythus S.E.) compared with the pretreatment with PBS.The expressionof FcR and H2O2 production were significantly reduced We also used P.gingivalis S.E.to compare with the effect of B.forsythus S.E.. After the pretreatment with P.gingivalis S.E., the expression of FcR, LEA-1 molecule, CR1, H2O2 production and bacteriocidal activity of PMNs were significantly reduced, except for CR3 which was significantly increased, compared with the pretreatment with PBS.These results suggest that B.forsythus has similar protease to P.gingivalis , but also has several differential factors or mechanisms to PMNs function. Less