Monefeldt K, Helgeland K, Tollefsen T
Department of Periodontology, Dental Faculty University of Oslo, Norway.
J Clin Periodontol. 1995 Jan;22(1):45-51. doi: 10.1111/j.1600-051x.1995.tb01769.x.
This study tested the hypothesis that in vitro cleavage of C3 could be triggered with similar case in serum samples from patients with adult periodontitis (n = 26) as in samples from periodontally healthy subjects (n = 13). A lipoteichoic acid, a lipopolysaccharide and an aggregated IgG served as activators of complement. On the average, the periodontitis group generated significantly (p < 0.01) more C3d activation fragments than did the healthy group, as judged from rocket immunoelectrophoresis measurements. Cleavage of C4 and factor B were then assayed through immunoblotting, without prior purification of the sera. C4c fragments were seen in all activated samples, the healthy group causing significantly (p < 0.05) more C4 conversion than did the periodontitis group. Cleavage of factor B, taken as a measure of soluble amplification convertase formation, was about equal between the groups. We inferred therefore that the 2 groups produced comparable amounts of C3b. The results suggested, however, that periodontitis sera favour breakdown of the opsonin C3b, most likely by activating the regulatory proteins factor H and I. Lipoteichoic acid, causing moderate depletion of C4 and factor B, produced significantly (p < 0.01) more C3d fragments than the other two activators examined. It may be that complement activation is down-regulated in periodontitis sera, perhaps at the expense of adequate local opsonic function.
与牙周健康受试者（n = 13）的血清样本相比，成人牙周炎患者（n = 26）的血清样本在体外能以类似情况触发C3裂解。脂磷壁酸、脂多糖和聚集的IgG作为补体激活剂。根据火箭免疫电泳测量结果判断，平均而言，牙周炎组产生的C3d激活片段明显（p < 0.01）多于健康组。然后通过免疫印迹法检测C4和B因子的裂解情况，无需事先纯化血清。在所有激活的样本中均可见C4c片段，健康组导致的C4转化明显（p < 0.05）多于牙周炎组。作为可溶性扩增转化酶形成指标的B因子裂解在两组之间大致相等。因此我们推断两组产生的C3b量相当。然而，结果表明，牙周炎血清有利于调理素C3b的分解，很可能是通过激活调节蛋白H因子和I因子。导致C4和B因子适度消耗的脂磷壁酸产生的C3d片段明显（p < 0.01）多于其他两种检测的激活剂。可能在牙周炎血清中补体激活受到下调，或许是以牺牲足够的局部调理功能为代价。
