不同龋敏感人群唾液富酪蛋白对致龋细菌粘附影响的比较

The effects of salivary statherin in different caries-risk individual on adherence of cariogenic bacteria in vitro

目的比较不同龋敏感人群唾液富酪蛋白(SalivaryStatherin)含量的差别,并观察唾液富酪蛋白对牙菌斑中两种主要细菌(变形链球菌和血链球菌)粘附能力的影响,探讨富酪蛋白与龋病的关系。方法用高效疏水色谱分离提纯唾液富酪蛋白,对比分析15名无龋者(DMFT =0 )及15名高龋者(DMFT≥6 )唾液中富酪蛋白的含量,并用全唾液及提纯的不同浓度的富酪蛋白作为实验性获得性膜成分,观察经放射性同位素3 H -胸腺嘧啶核苷酸(3 H -TDR)标记的变形链球菌和血链球菌对羟磷灰石的粘附情况。结果高龋个体唾液富酪蛋白的浓度明显较无龋者唾液富酪蛋白的浓度低(P <0 .0 5 )。富酪蛋白明显促进变形链球菌对羟磷灰石(Hydroxyapatite,HAP)的粘附且其促进作用的大小与其浓度有关(P <0 .0 5 )。而唾液富酪蛋白对血链球菌的粘附无明显影响(P >0 .0 5 )。不同龋敏感人群相同浓度的唾液富酪蛋白对S .mutans粘附的影响无明显差异(P >0 .0 5 )。结论唾液富酪蛋白的含量具有个体差异性,而且对不同细菌粘附的影响不同,从而可能导致不同个体、不同牙面对龋敏感度不同。

Objective To compare the salivary statherin concentration in different caries risk individuals; to investigate the effects of salivary statherin on adherence of two major cariogenic bacteria, Streptococcus mutans (S. mutans) and Streptococcus sanguis (S. sanguis) and the correlation between the salivary statherin and dental caries.Methods Whole salivary statherin samples of different caries risk individuals, 15 caries-free (DMFT = 0) and 15 caries active (DMFT≥6), were purified by means of high performance hydrophobic interaction chromatography (HPHIC). The purified statherin was further examined by SDS-PAGE electrophoresis and amino acid analysis. We observed the adherence of S. mutans (serotype c, 7H) and S. sanguinis, (ATCC10557) to hydroxyapatite (HAP), which was covered by purified statherin. The whole saliva (positive control) and PBS buffer (negative control) were used as experimental pellicles respectively.Results ①The concentration of salivary statherin was significant lower in high caries-risk individuals compared to caries-free individual (P<~0.05 ).②Statherin promotes the adherence of S. mutans to HAP and the adherence was positively correlated with the concentration of statherin (P<~0.05 ).③There was a lack of significant correlation between the statherin concentration and adherence of S. sanguis.Conclusion The concentration of salivary statherin varies among different individuals. The statherin has different effects on the adherence of different bacteria to HAP, resulting in the different caries risk in different individuals as well as different tooth surfaces.