Hylkema M N, Huygen H, Kramers C, vd Wal T J, de Jong J, van Bruggen M C, Swaak A J, Berden J H, Smeenk R J
Department of Autoimmune Diseases, The Netherlands Red Cross Blood Transfusion Service (C.L.B.), Amsterdam.
J Immunol Methods. 1994 Mar 29;170(1):93-102. doi: 10.1016/0022-1759(94)90249-6.
The measurement of anti-dsDNA antibodies is important for the diagnosis and the follow-up of patients with systemic lupus erythematosus (SLE). For routine detection of anti-dsDNA, the Farr assay and the immunofluorescence technique (IFT) on Crithidia luciliae proved to be very useful. The anti-dsDNA ELISA is not used for routine purposes in our institute since it is flawed by false-positive results due to binding of negatively charged (immune) complexes to the employed precoat (protamine sulphate). Recently, a new anti-dsDNA ELISA has been described in which photobiotinylated dsDNA is coated to streptavidin coated plates. To investigate whether this modified ELISA is more specific than the classical anti-dsDNA ELISA, we tested sera of patients with SLE (n = 51), myasthenia gravis (MG, n = 25), rheumatoid arthritis (RA, n = 25) and Sjögren's syndrome (SS, n = 23) and sera of healthy blood bank donors (BBD, n = 25). In both assays the sera of the SLE patients gave significantly higher values than the sera of healthy blood bank donors. In the classical ELISA, 84% of the sera from patients with RA and 28% of sera of patients with MG were found positive. For the modified assay the figures were 8% and 24%, respectively. This modified ELISA was further studied and clinically evaluated by comparing it with the classical anti-DNA ELISA and two other anti-DNA assays (Farr assay and IFT), using 500 sera sent to our institute for routine anti-DNA determination and sera of an additional 75 healthy blood bank donors. Quantitatively, both ELISAs showed the same high degree of correlation with the IFT. The modified ELISA gave a better correlation with the Farr assay than the classical anti-DNA ELISA. From our data we conclude that the ELISA using photobiotinylated DNA is a more reliable assay than the classical anti-DNA ELISA.
抗双链DNA抗体的检测对于系统性红斑狼疮（SLE）患者的诊断和随访至关重要。对于抗双链DNA的常规检测，Farr试验和针对利什曼原虫的免疫荧光技术（IFT）已被证明非常有用。抗双链DNA酶联免疫吸附测定（ELISA）在我们研究所不用于常规检测，因为由于带负电荷的（免疫）复合物与所用预包被物（硫酸鱼精蛋白）结合，该方法存在假阳性结果的缺陷。最近，一种新的抗双链DNA ELISA已被报道，其中光生物素化的双链DNA被包被在链霉亲和素包被的板上。为了研究这种改良的ELISA是否比经典的抗双链DNA ELISA更具特异性，我们检测了SLE患者（n = 51）、重症肌无力（MG，n = 25）、类风湿性关节炎（RA，n = 25）和干燥综合征（SS，n = 23）患者的血清以及健康血库供者（BBD，n = 25）的血清。在两种检测中，SLE患者的血清值均显著高于健康血库供者的血清值。在经典ELISA中，发现84%的RA患者血清和28%的MG患者血清呈阳性。对于改良检测，相应数字分别为8%和24%。通过将这种改良的ELISA与经典抗DNA ELISA和另外两种抗DNA检测方法（Farr试验和IFT）进行比较，使用500份送至我们研究所进行常规抗DNA测定的血清以及另外75名健康血库供者的血清，对这种改良的ELISA进行了进一步研究和临床评估。在定量方面，两种ELISA与IFT均显示出相同高度的相关性。改良后的ELISA与Farr试验的相关性优于经典抗DNA ELISA。根据我们的数据，我们得出结论，使用光生物素化DNA的ELISA比经典抗DNA ELISA是一种更可靠的检测方法。
