不同方法检测NMO-IgG/抗AQP4抗体滴度的比较

【目的】旨在比较鼠脑法和细胞法检测中国人视神经脊髓炎(NMO)疾病谱(NMOSD)的滴度是否具有一致性。【方法】每个样本分别采用鼠脑法和细胞法检测,阳性血清采取倍比稀释以确定最终稀释倍数。应用盲法检测血清NMO-IgG/抗水通道蛋白4(AQP4)110例,其中视神经脊髓炎19例,复发性视神经炎(RON)17例,纵形扩展性脊髓炎(LETM)13例,多发性硬化(MS)31例,健康对照(HC)30例;对其检测的阳性率和滴度进行分析,并比较滴度与脊髓病变长度的相关性。【结果】大部分样本用两种方法检测的滴度之间都缺乏一致性。NMO组患者NMO-IgG/抗AQP4抗体鼠脑法(63.2%,12/19),细胞法(89.5%,17/19),RON组鼠脑法(47.1%,8/17),细胞法(70.6%,12/17),LETM组鼠脑法(46.2%,6/13),细胞法(69.2%,9/13),MS组鼠脑法(6.5%,2/31),细胞法(9.7%,3/31)。鼠脑法和细胞法检测所得到的NMOSD患者NMO-IgG/AQP4抗体滴度均和脊髓病变的长度无线性相关性,两种检测方法之间也缺乏滴度线性相关性。【结论】鼠脑法和细胞法检测抗体滴度的不一致性提示有必要进行多因素相关性研究以探讨影响两种检测方法抗体滴度的因素。

Comparative Analysis of Methods for Titrating Anti-aquaporin-4 Antibodies in Neuromyelitis Optica Spectrum

【Objective】 This study was aimed to investigate the titer consistency in parallel between tissue-based IIFA and cell-based IIFA in Chinese patients with neuromyelitis optica(NMO) spectrum disorders.【Methods】 Every sample was tested by the tissue-based IIFA and cell-based IIFA separately.Positive serum samples were titrated in doubling dilutions,to ascertain the maximum dilution that yielded positive results separately.We assessed the seroprevalence and the titer consistency of anti-aquaporin-4 antibodies of serum samples from patients with neuromyelitis optica(NMO,19),recurrent optic neuritis(RON,17),longitudinally extensive transverse myelitis(LETM,13),multiple sclerosis(MS,31),health control(HC,30).Moreover,we analyzed the relation of anti-aquaporin-4 antibody titers and spinal cord lesions on MRI.【Results】 We noticed lack of concordance in titer detection in most samples between the two techniques.We found 63.2%(12/19) of NMO patients were seropositive for AQP4 antibodies by tissue-based IIFA versus 89.5%(17/19) by cell-based IIFA.47.1%(8/17) of RON patients were seropositive for AQP4 antibodies by tissue-based IIFA versus 70.6%(12/17) by cell-based IIFA.46.2%(6/13)of LETM patients were seropositive for AQP4 antibodies by tissue-based IIFA versus 69.2%(9/13) by cell-based IIFA.6.5%(2/31) of MS patients were seropositive for AQP4 antibodies by tissue-based IIFA versus 9.7%(3/31) by cell-based IIFA.The lengths of spinal cord lesions on MRI were not correlated with the titers of anti-AQP4 antibody in both assays.The two assays have no linear dependence in measuring this antibody titer.【Conclusion】 The current discrepancy between the two assays implies the necessity to study the potential impact on titers in both assays.