Nakakuma H, Nagakura S, Kawaguchi T, Horikawa K, Kagimoto T, Kawakita M, Tomita M, Takatsuki K
Second Department of Internal Medicine, Kumamoto University Medical School, Japan.
Int J Hematol. 1992 Apr;55(2):121-5.
Decay-accelerating factor (DAF) is a complement regulatory membrane protein that is often absent from the cell surface of blood cells in paroxysmal nocturnal hemoglobinuria (PNH). DAF has also recently been found in the body fluids of healthy individuals. However, its precise structure and biological significance are not yet clear. To clarify the clinical and pathological implications of free DAF, we measured plasma DAF levels in PNH patients, using a newly developed quantitative enzyme-linked immunosorbent assay (ELISA), with a measurable range between 0.2-12 ng, for soluble DAF. ELISA assays revealed significantly increased plasma DAF levels in PNH patients (258 +/- 150 ng/ml, mean +/- S.D., n = 9) as compared with healthy controls (80 +/- 41 ng/ml, n = 17) (p less than 0.01). Taken together with the finding that DAF is synthesized in and released extracellularly from affected PNH cells, plasma DAF levels would be useful for clinical diagnosis and for the quantitative evaluation of the clonal expansion of affected cells in PNH.
衰变加速因子（DAF）是一种补体调节膜蛋白，在阵发性夜间血红蛋白尿（PNH）患者的血细胞表面通常不存在。最近在健康个体的体液中也发现了DAF。然而，其精确结构和生物学意义尚不清楚。为了阐明游离DAF的临床和病理意义，我们使用新开发的定量酶联免疫吸附测定（ELISA）测量了PNH患者的血浆DAF水平，该方法可测量的可溶性DAF范围为0.2 - 12 ng。ELISA分析显示，与健康对照（80 +/- 41 ng/ml，n = 17）相比，PNH患者的血浆DAF水平显著升高（258 +/- 150 ng/ml，平均值 +/- 标准差，n = 9）（p < 0.01）。结合DAF在受影响的PNH细胞中合成并释放到细胞外的发现，血浆DAF水平将有助于临床诊断和对PNH中受影响细胞克隆扩增的定量评估。
