Fishman P S, Drachman D B
Neurology Service, Baltimore VAMC, MD, USA.
Neurology. 1995 Aug;45(8):1551-4. doi: 10.1212/wnl.45.8.1551.
The hypothesis that abnormal antibodies may be involved in the pathogenesis of ALS has been supported in part by IgG's being present within motoneurons of ALS patients more frequently than in motoneurons of controls. IgG, as well as other serum proteins, is also present in motoneurons of normal human and animal spinal cords. We attempted to determine whether the IgG found in motoneurons of ALS patients was localized by an immune-specific or nonspecific process. To address this question, we used immunocytochemistry to evaluate the presence and relative density of different serum proteins in spinal cords from nine patients with ALS. Both IgG and alpha 2-macroglobulin (alpha 2Mac) were present in motoneurons in all nine cases. More important, there was a close concordance between the IgG and alpha 2Mac immunolabeling of motoneurons. The presence of a nonimmune plasma protein--alpha 2Mac--in a similar distribution to IgG and with a similar intensity implies that the internalization of these proteins in motoneurons of patients with ALS is best explained by a nonselective mechanism of endocytosis of extracellular fluid.
异常抗体可能参与肌萎缩侧索硬化症（ALS）发病机制的假说，部分得到了如下证据的支持：与对照组运动神经元相比，ALS患者运动神经元中更频繁地出现免疫球蛋白G（IgG）。IgG以及其他血清蛋白，也存在于正常人类和动物脊髓的运动神经元中。我们试图确定在ALS患者运动神经元中发现的IgG是通过免疫特异性还是非特异性过程定位的。为了解决这个问题，我们使用免疫细胞化学方法评估了9例ALS患者脊髓中不同血清蛋白的存在情况和相对密度。在所有9例病例中，运动神经元中均存在IgG和α2-巨球蛋白（α2Mac）。更重要的是，运动神经元的IgG和α2Mac免疫标记之间存在密切的一致性。一种非免疫血浆蛋白——α2Mac——以与IgG相似的分布和相似的强度存在，这意味着这些蛋白在ALS患者运动神经元中的内化，最好用细胞外液的非选择性内吞机制来解释。
