Nobile-Orazio E, Hays A P, Latov N, Perman G, Golier J, Shy M E, Freddo L
Neurology. 1984 Oct;34(10):1336-42. doi: 10.1212/wnl.34.10.1336.
Some patients with neuropathy have IgM M-proteins that bind to myelin and to myelin-associated glycoprotein (MAG). We compared the binding properties of a human anti-MAG M-protein with three mouse monoclonal anti-MAG antibodies (GEN-S1, GEN-S3, GEN-S8) and with a mouse monoclonal antibody (HNK-1) that binds to both MAG and to human natural killer cells. The antibodies GEN-S1, GEN-S3, and GEN-S8 bound to different epitopes in the polypeptide portion of MAG as shown by peptide mapping, deglycosylation and competitive binding studies. The M-protein and HNK-1 bound to both CNS and PNS MAG and to several additional protein bands of 70K, 30K, 26K, and 23K daltons in peripheral, but not in central myelin; they did not bind to deglycosylated MAG. The M-protein and HNK-1 immunostained myelin diffusely, whereas GEN-S8 immunostained only the periaxonal and outer regions of myelin sheath, and there was no staining with GEN-S1 or GEN-S3. The human M-proteins probably bind to a carbohydrate moiety in MAG that is also present in other PNS myelin proteins. This may explain the observed differences in immunostaining and the sparing of the CNS in patients with anti-MAG M-proteins.
一些患有神经病变的患者体内存在能与髓磷脂及髓磷脂相关糖蛋白（MAG）结合的IgM M蛋白。我们比较了一种人抗MAG M蛋白与三种小鼠单克隆抗MAG抗体（GEN-S1、GEN-S3、GEN-S8）以及一种能同时与MAG和人自然杀伤细胞结合的小鼠单克隆抗体（HNK-1）的结合特性。肽图谱分析、去糖基化及竞争性结合研究表明，抗体GEN-S1、GEN-S3和GEN-S8与MAG多肽部分的不同表位结合。M蛋白和HNK-1能与中枢神经系统（CNS）和外周神经系统（PNS）的MAG以及外周髓磷脂中70K、30K、26K和23K道尔顿的几种额外蛋白条带结合，但不与中枢髓磷脂中的这些蛋白结合；它们不与去糖基化的MAG结合。M蛋白和HNK-1对髓磷脂进行弥漫性免疫染色，而GEN-S8仅对髓鞘的轴突周围和外部区域进行免疫染色，GEN-S1或GEN-S3则无染色。人M蛋白可能与MAG中的一个碳水化合物部分结合，该部分也存在于其他PNS髓磷脂蛋白中。这可能解释了抗MAG M蛋白患者中观察到的免疫染色差异及中枢神经系统未受影响的现象。
