Department of Human Pathology, Gunma University Graduate School of Medicine, Showa, Maebashi, Gunma, Japan.
Neuropathology. 2012 Dec;32(6):587-94. doi: 10.1111/j.1440-1789.2012.01299.x. Epub 2012 Feb 28.
Neuromyelitis optica (NMO) is an inflammatory demyelinating and necrotizing disorder of the CNS that mainly affects the optic nerve and spinal cord. The etiology is still uncertain; however, the discovery of serum anti-aquaporin-4 (AQP4) autoantibody is becoming the center of attention, and a new hypothesis is emerging that NMO is essentially astrocytopathy provoked by this autoantibody. In this study, we focused on corpora amylacea (CA), glycoproteinaceous inclusions in astrocytic processes. We examined 57 lesions in nine cases of NMO spectrum disorder, and demonstrated that CA were phagocytized by macrophages in 42 lesions (74%) of eight cases, while phagocytized figures were not seen in unaffected areas. Phagocytized CA were frequently encountered in early-phase lesions still retaining myelin structures, while fewer or none were found in chronic destructive lesions. Moreover, phagocytized CA were significantly smaller in diameter than intact ones, and CA were decreased or absent in most lesions assessed. These findings suggest the following pathophysiological process: the astrocytes are affected at an early phase in NMO, CA are expelled from the astrocytes and phagocytized by macrophages finally leading to clearance. A phagocytized figure and subsequent loss of CA can be a histological hallmark of astrocytic injury of NMO.
视神经脊髓炎（NMO）是一种主要影响视神经和脊髓的中枢神经系统炎症性脱髓鞘和坏死性疾病。病因仍不确定；然而，血清抗水通道蛋白-4（AQP4）自身抗体的发现正成为关注的焦点，一种新的假说正在出现，即 NMO 本质上是由这种自身抗体引起的星形胶质细胞病。在本研究中，我们专注于脑实质淀粉样体（CA），即星形胶质细胞突起中的糖蛋白包涵体。我们检查了 9 例 NMO 谱障碍中的 57 个病变，并证明在 8 例中的 42 个病变（74%）中，CA 被巨噬细胞吞噬，而在未受影响的区域则未观察到吞噬现象。吞噬的 CA 在仍保留髓鞘结构的早期病变中经常遇到，而在慢性破坏性病变中则较少或没有。此外，吞噬的 CA 的直径明显小于完整的 CA，在大多数评估的病变中，CA 减少或消失。这些发现表明了以下病理生理过程：在 NMO 的早期阶段，星形胶质细胞受到影响，CA 从星形胶质细胞中排出，最终被巨噬细胞吞噬清除。吞噬现象和随后的 CA 缺失可能是 NMO 星形胶质细胞损伤的组织学标志。
