抗体阴性重症肌无力患者血浆及其IgG和非IgG组分对AChR功能及α-BuTx结合试验的影响

Effects of Plasma,IgG,and Non-IgG Fractions Seronegative Myasthenia Gravis Patients on the Acetylcholine Receptor Function and Alphabungarotoxin Binding Test

利用TE671细胞表达烟碱型乙酰胆碱受体（AChR）的特性，探讨乙酰胆碱受体抗体（AChRab）阴性重症肌无力（MG）患者血浆和从中提取的IgG和非-IgG组分对α-银环蛇毒素（α-BuTx）结合试验及AChR功能的影响。结果表明抗体阴性MG血浆及其IgG和非IgG组分对α－BuTx结合试验均无影响，而对AChR功能有抑制作用，抑制率分别为（50±5）％、（24±6）％和（48±7）％。提示在抗体阴性MG发病过程中非IgG组分可能起主导作用。

The aim of present study is to characterlze the action of plasma, IgG, and non-IgG fractions derived from acetylcholine receptor antibody negative myasthenia gravis (seronegative MG) on the acetylcholine receptor (AChR) function and alpha bungarotoxin (α-BuTx) binding to AChR. Results showed that α-BuTx binding to AChR was not inhibited by plasma,IgG, and non-IgG fractions purified from seronegative MG. On the contrary carbachol induced sodium influx was inhibited by these agents. The percentage of inhibitory effects of plasma, IgG, and non-IgG fractions were (50±5) %, (24± 6) % and (48± 7) %, respectively. Data suggest non-IgG fractions play important role in causing myasthenic symptoms in seronegative MG.