Monefeldt K, Tollefsen T
Department of Microbiology, Dental Faculty, University of Oslo, Norway.
J Clin Periodontol. 1993 Mar;20(3):186-92. doi: 10.1111/j.1600-051x.1993.tb00342.x.
This study describes activation of serum complement by lipoteichoic acid (LTA) from Streptococcus mutans OMZ 176, while in solution. Serum from 16 healthy students was taken. Test samples were incubated with increasing doses (1-5,000 micrograms/ml) of LTA or lipopolysaccharide (LPS) from Escherichia coli 0111:B4 for 1 h at 37 degrees C; then assayed for degradation of C3, C4 or factor B by crossed immunoelectrophoresis. Each preparation caused a significant (p < 0.05) dose-dependent conversion of C3. The response curves obtained were not statistically different. LPS was a stronger activator of the alternative pathway than LTA, as judged from analysis of C3 degradation in the presence of Mg2+/EGTA, and from their effects on factor B cleavage. LTA caused, however, pronounced alterations in the shape of C4 precipitation in the gels. Functional (hemolytic) assays showed that, when tested at 200 micrograms/ml, LTA and LPS triggered significant (p < 0.05) consumptions of both classical and alternative pathway proteins. LPS was a significantly (p < 0.05) stronger activator than LTA. Apparently, the C3 degradation found for this LTA involved the alternative pathway to a small extent; thus some other mechanism of fluid-phase C3 cleavage seemed also to be operative.
本研究描述了变形链球菌OMZ 176的脂磷壁酸（LTA）在溶液中激活血清补体的情况。采集了16名健康学生的血清。将测试样品与递增剂量（1 - 5000微克/毫升）的LTA或大肠杆菌0111:B4的脂多糖（LPS）在37℃下孵育1小时；然后通过交叉免疫电泳分析C3、C4或B因子的降解情况。每种制剂都引起了C3的显著（p < 0.05）剂量依赖性转化。获得的反应曲线无统计学差异。从Mg2+/EGTA存在下C3降解的分析以及它们对B因子裂解的影响判断，LPS是比LTA更强的替代途径激活剂。然而，LTA导致凝胶中C4沉淀的形状发生明显改变。功能（溶血）试验表明，当以200微克/毫升进行测试时，LTA和LPS引发了经典途径和替代途径蛋白的显著（p < 0.05）消耗。LPS是比LTA显著更强（p < 0.05）的激活剂。显然，这种LTA导致的C3降解在一定程度上涉及替代途径；因此，液相C3裂解的一些其他机制似乎也在起作用。
