Lagrue G, Branellec A, Intrator L, Moisy M, Sobel A
Nouv Presse Med. 1979 Mar 24;8(14):1153-6.
Measurement of serum C3 does not provide precise informations concerning an eventual consumption of this complement component during an immunological process. An increased synthetic rate may compensate an accelerated catabolism. The study of breakdown products of C3, such as C3d is a more sensitive approach of the role of complement in some immunological disorders. Therefore C3d was measured in the serum of patients with chronic non systemic glomerular diseases. High values of serum C3d were found in all cases of hypocomplementemic glomerulonephritis. Circulating C3d was also increased to a lower extent, in patients with normocomplementemic nephritis such as minimal change disease, mesangial nephritis with IgA deposits and membraneoproliferative (type I) glomerulonephritis. The data suggested the involvement of complement in a number of glomerulonephritis. Participation of complement in immunological disorders particularly in chronic non systemic glomerulonephritis could require a reevaluation when functional tests are performed in addition to static measurements.
血清C3的测量并不能提供有关免疫过程中该补体成分最终消耗情况的精确信息。合成速率增加可能会补偿加速的分解代谢。对C3裂解产物（如C3d）的研究是一种更敏感的方法，可用于了解补体在某些免疫性疾病中的作用。因此，对慢性非系统性肾小球疾病患者的血清进行了C3d检测。在所有低补体血症性肾小球肾炎病例中均发现血清C3d值较高。在补体正常的肾炎患者中，如微小病变病、IgA沉积的系膜性肾炎和膜增生性（I型）肾小球肾炎，循环C3d也有一定程度的升高。这些数据提示补体参与了多种肾小球肾炎。当除了静态测量外还进行功能测试时，补体参与免疫性疾病（尤其是慢性非系统性肾小球肾炎）的情况可能需要重新评估。
