用快速斑点免疫金渗滤法检测抗SSA抗体

目的建立一种简便、快速、可靠的检测抗SSA抗体的方法。方法将重组的SSA抗原包被于硝酸纤维素(NC)膜上,以胶体金标记的葡萄球菌蛋白A(StaphylococusproteinA,SPA)作为显示剂,建立一种检测抗SSA抗体的快速斑点免疫金渗滤法(dotimmunogoldfiltrationassay,DIGFA)。结果本法对系统性红斑狼疮(SLE)阳性率为100%,对皮肌炎(DM)阳性率为100%,狼疮性肾炎(LN)阳性率为75%,本法与免疫印迹法(IBT)的符合率为94.1%。IBT法阴性的50例病人中,本法检出3例阳性病例(其ANA均为阳性);健康体检50例均为阴性。结论本法简便、快速、可靠,整个检测过程只需2min,不需其他特殊设备。

Detection for anti-SSA antibodies by dot immunogold filtration assay

Objective To establish a rapid,simple and reliable method for detection of anti-SSA antibodies.Methods A new dot immunogold filtration assay (DIGFA) was developed,in which the recombinant SSA protein was bound to nitrocellulose (NC) membrane and colloidal gold-labeled staphylococus protein A (SPA) was used as an indicator.Results Sera from patients with systemic lupus erythematosus,dermatomyositis and lupus nephrosis were examined with the developed DIGFA.The positive rate in the patients with systemic lupus erythematosus,dermatomyositis and lupus nephrosis were 100%,100% and 75% respectively.The agreement between DIGFA and immunoblotting test (BT) was 94.1% as calculated by Kappa statistical method.Among 50 SSA-negative patients detected by BT,3 patients whose antinuclear antibodies (ANA) were positive were found to be SSA-positive by DIGFA detection.None of healthy controls was SSA-positive in DIGFA detection.The results showed that the sensitivity of DIGFA achieved the equivalent level of BT,and its specificity was similar to that of BT or even better than BT.The reproducibility and stability of DIGFA were also satisfied.Conclusions DIGFA is a simple,rapid and reliable assay whose performance could be completed in 2 minutes without any special equipment required.Thus DIGFA may be used as a routine assay for the detection of anti-SSA antibodies.