Bourke B E, Moss I K, Maini R N
J Immunol Methods. 1982;48(1):97-108. doi: 10.1016/0022-1759(82)90214-9.
A method is described for quantitative measurement of C3d in plasma and synovial fluid by the use of rocket immunoelectrophoresis after fractionation of the samples with 22% polyethylene glycol. This method has the advantage over radial immunodiffusion of being more sensitive (detecting C3d down to 3 mg/l) whilst proving equally reproducible. Investigations indicate that the collection of blood samples in EDTA prevents in vitro activation of C3 even after storage for up to 6 h at room temperature and up to 12 weeks at -70 degrees C. Elevated levels of C3d were found in a proportion of SLE and RA plasma samples and in synovial fluids from patients with inflammatory synovitis. It is suggested that C3 conversion in vivo may be assessed by measurement of C3d by the technique described, and when used in conjunction with measurements of complement components and immune complexes, offers a means of investigating complement catabolism by the classical and alternative pathways.
描述了一种通过火箭免疫电泳对血浆和滑液中的C3d进行定量测量的方法，该方法是在样品用22%聚乙二醇分级分离后进行的。与放射免疫扩散相比，该方法具有更灵敏的优点（可检测低至3mg/l的C3d），同时具有同样的可重复性。研究表明，在乙二胺四乙酸（EDTA）中采集血样可防止C3的体外激活，即使在室温下储存长达6小时以及在-70℃下储存长达12周也是如此。在一部分系统性红斑狼疮（SLE）和类风湿关节炎（RA）血浆样本以及炎症性滑膜炎患者的滑液中发现C3d水平升高。有人提出，通过所述技术测量C3d可评估体内的C3转化，并且当与补体成分和免疫复合物的测量结合使用时，提供了一种通过经典途径和替代途径研究补体分解代谢的方法。
