不同基质的间接免疫荧光法同时检测血清和脑脊液水通道蛋白4抗体在视神经脊髓炎诊断中的应用

Diagnostic value of serum and cerebral spinal fluid aquaporin 4-IgG detected by indirect immunofluorescence assays using different base in neuromyelitis optica

目的 探讨基于猴视神经和稳定转染水通道蛋白4 （AQP4）细胞的间接免疫荧光法（indirect immunofluorescence assay,ⅡFA）同时检测血清和脑脊液AQP4-IgG在视神经脊髓炎（NMO）中的应用.方法 应用猴视神经/细胞IIFA,同时检测32例NMO、41例多发性硬化（MS）和33例神经系统非炎性疾病（NIND）患者血清和脑脊液AQP4-IgG以及20名健康人血清AQP4-IgG,并进行对比分析.结果 （1）无论采用视神经IIFA还是细胞IIFA,与MS和NIND患者及健康人相比,NMO患者血清AQP4-IgG阳性率显著升高[视神经IIFA：NMO 46.9％ （15/32）,MS 7.3％ （3/41）,NIND3.0％ （1/33）,健康人0（0/20）,P＜0.01;细胞IIFA：NMO 84.4％ （27/32）,MS 2.4％ （1/41）,NIND 3.0％ （1/33）,健康人0（0/20）,P＜0.01],与MS及NIND患者相比,NMO患者脑脊液AQP4-IgG阳性率显著升高[视神经ⅡFA：NMO 21.9％ （7/32）,MS 0（0/41）,NIND 0（0/33）,P＜0.01;细胞IIFA：NMO 56.3％ （18/32）,MS 0 （0/41）,NIND 0 （0/33）,P＜0.01];血清标本（视神经IIFA46.9％,细胞IIFA 84.4％）在诊断NMO时的敏感度明显高于脑脊液标本（视神经IIFA 21.9％,P＜0.05;细胞IIFA 56.3％,P＜0.05）,两种标本特异度差异无统计学意义;同时检测血清和脑脊液,可提高血清AQP4-IgG诊断的敏感度（视神经IIFA：46.9％比50.0％;细胞IIFA：84.4％比87.5％）,而特异度无改变.（2）无论血清还是脑脊液标本,与视神经IIFA（血清标本46.9％,脑脊液标本21.9％）相比,细胞IIFA具有更好的敏感度（血清标本84.4％,P＜0.01;脑脊液标本56.3％,P＜0.01）,特异度差异无统计学意义.结论 （1）视神经IIFA检测AQP4-IgG有助于NMO诊断,但敏感度低于细胞IIFA;（2）同时检测血清和脑脊液AQP4-IgG在诊断NMO时具有更好的临床价值.

Objective To explore the diagnostic value of serum and cerebral spinal fluid （CSF） aquaporin 4（AQP4）-IgG detected by indirect immunofluorescence assay （ⅡFA） using monkey optical nerve and AQP4 transfected cell as base in neuromyelitis optica （NMO）.Methods Serum and CSF AQP4-IgG in 32 NMO patients,41 multiple sclerosis （MS） patients,33 non-inflammatory neurological disease （NIND） patients and serum AQP4-IgG in 20 healthy controls （HC） were detected by monkey optical nerve/AQP4 transfected cell-based IIFA.Results （1） In both optical nerve and AQP4 transfected cell based IIFA,compared with MS,NIND and HC,the patients with NMO had significantly higher positive rate of AQP4-IgG in both serum （optical nerve-based IIFA：NMO 46.9% （15/32）,MS 7.3% （3/41）,NIND 3.0% （1/33）,HC 0 （0/20）,P 〈 0.01 ; cell-based IIFA：NMO 84.4% （27/32）,MS 2.4% （1/41）,NIND 3.0% （1/33）,HC 0 （0/20）,P 〈0.01） and CSF （optical nerve-based ⅡFA：NMO 21.9% （7/32）,MS 0 （0/41）,NIND 0 （0/33）,P 〈 0.01 ; cell-based IIFA：NMO 56.3% （18/32）,MS 0 （0/41）,NIND 0（0/33）,P〈0.01）; sensitivity of serum AQP4-IgG （optical nerve-based IIFA 46.9%; cell-based IIFA 84.4%） was significantly higher than that of CSF AQP4-IgG （optical nerve-based IIFA 21.9%,P 〈0.01 ; cell-based IIFA 56.3 %,P 〈 0.05）,while no significant difference was found in specificity between serum and CSF AQP4-IgG in diagnosing NMO; using combination of serum and CSF AQP4-IgG applied,the sensitivity increased （optical nerve-based IlFA 46.9% vs 50.0% ; cell-based IIFA 84.4% vs 87.5%） while specificity remained no change.（2） Compared with optical nerve-based IIFA （serum 46.9%,CSF 21.9%）,cell-based IIFA had higher sensitivity in diagnosing NMO （serum 84.4% ; CSF 56.3%,P 〈 0.01）,while no significant difference of specificity between these two methods.Conclusion It has better clinical value to detect serum and CSF AQP4-IgG at the same time by AQP4 transfected cell based IIFA in diagnosing NMO.