Wilkins J, Gallimore J R, Tennent G A, Hawkins P N, Limburg P C, van Rijswijk M H, Moore E G, Pepys M B
Abbott Diagnostics Division, Abbott Laboratories, North Chicago, IL 60064.
Clin Chem. 1994 Jul;40(7 Pt 1):1284-90.
Serum amyloid A (SAA), a sensitive acute-phase protein, is the precursor of AA fibrils in reactive amyloidosis. However, SAA is poorly immunogenic, and development and standardization of immunoassays of this protein have been difficult. We established an automated polyclonal/monoclonal microparticle capture enzyme immunoassay, standardized with the World Health Organization prospective reference standard for SAA. A stabilized concentrate of SAA was used for controls and calibrators. The assay range was 1-750 mg/L with CVs < 7% throughout. Plasma and serum gave identical results and no interferences were observed. Linear regression against radial immunodiffusion assay gave a slope of 1.04 (95% confidence interval 0.99-1.10), intercept of -9 mg/L (95% confidence interval -14-3), and residual SD (SEE) of 20 for samples containing < or = 200 mg/L (n = 173). In 105 apparently healthy adults the mean (SD) SAA concentration was 3.7 (3.6) mg/L, the median was 3.0 mg/L, and the range, 0.7-26.4 mg/L. In clinical acute-phase sera, values up to 2200 mg/L were seen. This method will facilitate measurement and investigation of SAA in clinical practice generally and in AA amyloidosis.
血清淀粉样蛋白A（SAA）是一种敏感的急性期蛋白，是反应性淀粉样变性中AA纤维的前体。然而，SAA的免疫原性较差，该蛋白免疫测定方法的开发和标准化一直很困难。我们建立了一种自动化的多克隆/单克隆微粒捕获酶免疫测定法，并以世界卫生组织SAA前瞻性参考标准进行标准化。使用稳定化的SAA浓缩物作为对照品和校准品。该测定范围为1 - 750 mg/L，全程变异系数（CV）< 7%。血浆和血清结果相同，未观察到干扰。与放射免疫扩散测定法的线性回归显示，对于SAA含量≤200 mg/L的样本（n = 173），斜率为1.04（95%置信区间0.99 - 1.10），截距为 - 9 mg/L（95%置信区间 - 14 - 3），剩余标准差（SEE）为20。在105名表面健康的成年人中，SAA浓度均值（标准差）为3.7（3.6）mg/L，中位数为3.0 mg/L，范围为0.7 - 26.4 mg/L。在临床急性期血清中，观察到的值高达2200 mg/L。该方法将有助于在临床实践中普遍测量和研究SAA，以及在AA淀粉样变性中进行相关研究。
