A sensitive non-isotopic assay for acetylcholine receptor autoantibodies

被引：35

作者：

Hewer, R ^{[1
]}

Matthews, I ^{[1
]}

Chen, S ^{[1
]}

McGrath, V ^{[1
]}

Evans, M ^{[1
]}

Roberts, E ^{[1
]}

Nute, S ^{[1
]}

Sanders, J ^{[1
]}

Furmaniak, J ^{[1
]}

Smith, BR ^{[1
]}

机构：

[1] RSR Ltd, FIRS Labs, Cardiff CF14 5DU, S Glam, Wales

来源：

CLINICA CHIMICA ACTA | 2006年 / 364卷 / 1-2期

关键词：

myasthenia gravis (MG); acetylcholine receptor (AChR); autoantibodies (Ab); ELISA;

D O I：

10.1016/j.cccn.2005.05.035

中图分类号：

R446 [实验室诊断]; R-33 [实验医学、医学实验];

学科分类号：

1001 ;

摘要：

Background: Detection and measurement of serum acetylcholine receptor autoantibodies (AChRAb) are useful in the diagnosis and management of myasthenia gravis (MG). An immunoprecipitation assay (IPA) based on AChR labelled with 125 I-a bungarotoxin is widely used for measurement of AChRAb, but a non-isotopic assay of sensitivity and specificity comparable to IPA is not available as yet. Methods: A new AChPAb ELISA, which is based on the ability of AChRAb to compete with 3 different AChR monoclonal antibodies (MAbs 1-3) for binding sites on affinity purified fetal and adult-type AChR preparations, is described. The sensitivity and specificity of the ELISA were assessed by comparing assay results with a conventional IPA. Results: There was good agreement between the IPA and the ELISA for measurement of AChRAb (r=0.85; n =83; p <0.001). 76/83 MG sera were positive in the ELISA, whilst 72/83 were positive by IPA. Eight sera were positive in the ELISA (inhibition range 18%-46%) but negative by IPA (0.33-0.47 nmol/L toxin bound) and 4 sera were negative in the ELISA (inhibition range - 1% to \15%) whilst positive by IPA (0.56-2.9 nmol/L toxin bound). Overall 80/83 (96%) of the MG sera were AChRAb positive in one or both assays. In addition, all 191 control serum samples which were negative for AChRAb by IPA were below or equal to 16% of inhibition in our ELISA. The AChRAb ELISA also showed good inter-assay and intra-assay precision. Conclusion: The AChRAb ELISA we have described has sensitivity and specificity at least as high as our current radioactive IPA. It has good precision and good handling characteristics making it suitable for routine use. (C) 2005 Elsevier B.V. All rights reserved.

引用

页码：159 / 166

页数：8

共 26 条

[1] Stable functional expression of the adult subtype of human muscle acetylcholine receptor following transfection of the human rhabdomyosarcoma cell line TE671 with cDNA encoding the epsilon subunit [J].