免疫牛乳清对变形链球菌粘附的影响

Effects of Immune Bovine Whey on Sucrose-dependent Adherence of Streptococcus mutans

目的 :研究免疫乳清对变形链球菌蔗糖依赖性粘附的影响。方法 :用来源于葡糖基转移酶过表达株B 2 9 33免疫孕牛获得的免疫牛奶和从未免疫孕牛获得的对照牛奶 ,分别观察两种乳清在 5种不同剂量条件下的细菌粘附率 ,并用扫描电镜观察粘附的形态学变化。结果 :对照乳清在 5种剂量条件下 ,变形链球菌的粘附率基本无变化。免疫乳清随着剂量的增加 ,细菌的粘附率呈下降趋势 ,从 10 0 μl时的 84 37% ,下降至 90 0 μl时的 5 8 5 9%。扫描电镜下见免疫乳清组细菌的细胞清晰 ,基质少。对照乳清组细菌的细胞则被大量的胶冻状基质包裹。结论 :免疫乳清可以抑制变形链球菌的蔗糖依赖性粘附。

Objective:The aim of this experiment is to explore the possible anti carious mechanisms of immune bovine whey.Methods:The immune milk was collected from cows immunized with cell associated glucosyltransferase(GFT) over expression strain B 29 33 of Streptococcus mutans(S.mutans) MT8148. The control milk was obtained from non immunized cows. The immune and control bovine whey were prepared by removing fat and casein.The effects of two kinds of bovine whey on sucrose dependent adherence of S.mutans MT8148 were examined by using TTY media with five different volumes of the immune and the control milk, 100,300,500,700 and 900μl respectively. The adherent rates were determined by reading the optical density. The adherent morphology was observed by using a scanning electron microscope(SEM). Results: There was no significant difference in adherence of S.mutans MT8148 cells to the smooth glass surface among five doses with those of the control whey. The immune bovine whey inhibited the adherence of S.mutans. The adherent percentage was 84 37% at 100μl and decreased by 58 59% at 900μl.The inhibition was does_dependent. The difference of adherent morphology between the immune and control whey was noticeable at 900μl. The SEM revealed that cells of S.mutans MT8148 with the control whey were covered by large quantities of gelatinous material,but cells with the immune whey were clearly distinguished. Conclusion: The immune whey has inhibitory potential against the sucrose dependent adherence of S.mutans.\;