Zilow G, Sturm J A, Rother U, Kirschfink M
Institute of Immunology, University of Heidelberg, FRG.
Clin Exp Immunol. 1990 Feb;79(2):151-7. doi: 10.1111/j.1365-2249.1990.tb05171.x.
In vivo and in vitro studies have shown that complement activation plays an important role in the pathogenesis of the adult respiratory distress syndrome (ARDS). In a prospective study of polytrauma patients at risk of ARDS (n = 38) complement parameters were determined over a period of 14 days in serial plasma samples (obtained every 6 h during the first 48 h). Polytrauma induced a rapid and remarkable complement activation. Low levels of the complement proteins C3, C4, C1 inhibitor (C1 INH) factor I and factor H during the first 48 h indicated complement consumption in all patients. Elevated C3a levels in the first few hours after injury were associated with the later development of ARDS. A more sensitive indicator than C3a alone was the calculated C3a:C3 ratio discriminating ARDS and non-ARDS patients. A second rise of C3a levels and C3a:C3 ratio from day 4 on paralleled the course of extravascular lung water. To assess the mode of complement activation, the activation-specific protein complexes C1rC1s-C1 INH and C3b(Bb)P were measured in some of the patients. We demonstrate that in the first 48 h complement activation occurred via the alternative pathway only and was later followed by an additional activation via the classical pathway. Our observations suggest that monitoring of C3a and C3 in plasma can identify polytrauma patients at high risk for ARDS at an early stage of the disease.
体内和体外研究表明，补体激活在成人呼吸窘迫综合征（ARDS）的发病机制中起重要作用。在一项对有ARDS风险的多发伤患者（n = 38）的前瞻性研究中，在连续14天内，每隔6小时（在前48小时内）采集系列血浆样本，测定补体参数。多发伤引起快速且显著的补体激活。在最初48小时内，补体蛋白C3、C4、C1抑制物（C1 INH）、因子I和因子H水平较低，表明所有患者均有补体消耗。受伤后头几个小时内C3a水平升高与ARDS的后期发展相关。比单独的C3a更敏感的指标是计算得出的C3a:C3比值，它可区分ARDS患者和非ARDS患者。从第4天开始，C3a水平和C3a:C3比值的第二次升高与血管外肺水的变化过程平行。为评估补体激活方式，在部分患者中检测了激活特异性蛋白复合物C1rC1s - C1 INH和C3b(Bb)P。我们证明，在最初48小时内补体激活仅通过替代途径发生，随后经典途径也被激活。我们的观察结果表明，监测血浆中的C3a和C3可以在疾病早期识别出有ARDS高风险的多发伤患者。
