抄録
In the present study the effects of sonicate preparation of oral microorganisms on the humoral immune responses were investigated in mouse spleen cell culture by the direct antibody plaque technique.
Actinomyces viscosus, Veillonella alcalescens, Fusobacterium nucleatum and Bacteroides melaninogenicus were cultured anaerobically in liquid growth media. Microbial cells were collected and lyophilized. After the bacterial suspension was sonicated and centrifuged, the supernatant was filtered sterilely and then heated for 30 minutes at 56°C. The protein content of the sonicates was determined according to the method of Lowry. Unsensitized and in vivo sensitized AKR mice spleen cells by the sonicates were suspended in RPMI 1640 medium containing 10% heat-inactivated fetus calf serum. Sheep red blood cells and three concentrations (10-3, 10-2, 10-1) of the sonicates were added to the spleen cell suspensions. The resulting preparations were incubated for 4 days at 37°C in an atmosphere of 5% CO2-95% air. The results were estimated by counting the numbers of direct plaque forming cell (PFC) in the spleen cell culture.
The following findings were obtained:
1. Non-heated sonicates with 10-3 and 10-2 concentrations from four oral microorganisms did show the enhancement of antibody formation.
2. The number of PFC increased after stimulation with 10-2 and 10-1 concentrations of the heated sonicates as compared with the control. The adjuvant indices with 10-1 concentration of the sonicates were as follows; A. viscosus: 6.6, V. alcalescens: 3.8, F. nucleatum: 2.4, B. melaninogenicus: 2.8.
3. The kinetic response of PEC to 10-2 concentration of four heated sonicates was characterized by an increase in the number of PFC on 3, 4, 5th day of cultivation and the number on 5th day was more six fold than the control.
4. It was suggested that four heated sonicates with 10-1 concentration were capable of inducing the polyclonal B cell.
5. In vivo sensitized mice spleen cells by the sonicates from A. viscosus, F. nucleatum, B. melaninogenicus increased in the number of PFC, while the number decreased after stimulation with V. alcalescens, when compared to unsensitized mice spleen cells.
