Kato H, Kogure K, Liu X H, Araki T, Itoyama Y
Department of Neurology, Tohoku University School of Medicine, Sendai, Japan.
Brain Res. 1996 Sep 23;734(1-2):203-12.
In order to evaluate the involvement of inflammatory reactions following focal cerebral ischemia in the rat, we immunohistochemically visualized microglial cells and blood-borne leukocytes (neutrophils and monocytes) using various antibodies directed against immunomolecules expressed on these cells. Focal cerebral ischemia was produced by intraluminal occlusion of the right middle cerebral artery for 1 h. The brains were perfusion-fixed at 4 h, 1 day, 3 days, 7 days and 14 days after ischemia. Frozen brain sections were prepared and stained with monoclonal antibodies to complement receptor type 3 (OX42), major histocompatibility complex (MHC) class I and class II antigens (OX18 and OX6, respectively), a pan-macrophage/monocyte marker (ED1), intercellular adhesion molecule-1 (ICAM-1), LFA-1 alpha chain (CD11a) and beta chain (CD18), and T cells (CD5). In ischemic areas where infarction developed later, microglial cells were destroyed (beginning at 4 h), neutrophils migrated (1-3 days), and then monocytes/macrophages infiltrated and covered the entire lesions (3-14 days). The invading leukocytes expressed CD11 and CD18 adhesion molecules on their cell surface while ICAM-1 was expressed on endothelial cells. In surrounding areas, in contrast, there was a rapid activation of microglia showing morphological changes and upregulation of OX42 immunoreactivity (4 h-7 days), especially in the transitional rim of the infarct (7 days). ED1 and MHC antigens were expressed on both activated microglia and invading leukocytes. Thus, developing infarction was accompanied by accumulation of inflammatory cells of both intrinsic (microglia) and extrinsic (leukocytes) origins. Thus, results suggest that the relative importance of each source is determined by the time after ischemia and the site within the lesion, and that the expression of immunological molecules plays an important role in eliciting such inflammatory reactions.
为了评估大鼠局灶性脑缺血后炎症反应的参与情况，我们使用针对这些细胞上表达的免疫分子的各种抗体，通过免疫组织化学方法观察小胶质细胞和血源性白细胞（中性粒细胞和单核细胞）。通过右侧大脑中动脉腔内闭塞1小时来产生局灶性脑缺血。在缺血后4小时、1天、3天、7天和14天对大脑进行灌注固定。制备冷冻脑切片，并用针对3型补体受体（OX42）、主要组织相容性复合体（MHC）I类和II类抗原（分别为OX18和OX6）、泛巨噬细胞/单核细胞标志物（ED1）、细胞间粘附分子-1（ICAM-1）、LFA-1α链（CD11a）和β链（CD18）以及T细胞（CD5）的单克隆抗体进行染色。在后来发生梗死的缺血区域，小胶质细胞被破坏（从4小时开始），中性粒细胞迁移（1 - 3天），然后单核细胞/巨噬细胞浸润并覆盖整个病变区域（3 - 14天）。侵入的白细胞在其细胞表面表达CD11和CD18粘附分子，而ICAM-1在内皮细胞上表达。相比之下，在周围区域，小胶质细胞迅速活化，表现出形态变化和OX42免疫反应性上调（4小时 - 7天），尤其是在梗死灶的过渡边缘（7天）。ED1和MHC抗原在活化的小胶质细胞和侵入的白细胞上均有表达。因此，正在发展的梗死伴随着内源性（小胶质细胞）和外源性（白细胞）来源的炎症细胞的积聚。因此，结果表明每种来源的相对重要性由缺血后的时间和病变内的部位决定，并且免疫分子的表达在引发此类炎症反应中起重要作用。
