SARS患者尸检肺组织的免疫组织化学观察

目的 通过对严重急性呼吸综合征(severe acute respiratory syndrome,SARS)肺组织病变的免疫组织化学研究,结合组织学观察,探讨SARS肺部病变的特点及发病机制。方法 以常规HE染色组织学观察结合CD8、CD20、CD34、LCA、CD56、CD68及AEl／AE3等单克隆抗体免疫组织化学染色,分别观察淋巴细胞、巨噬细胞、肺泡上皮细胞及肺毛细血管等在肺病变中的数目及分布特点,观察肺组织内血管变化、肺泡上皮增生以及机化和纤维化改变,从而分析SARS肺病变的特点。结果 从病变早期至早期纤维化,SARS肺组织中毛细血管数目增多,血管分布符合肺泡壁结构轮廓;炎细胞反应表现为淋巴细胞数目下降而巨噬细胞数目显著增多;Ⅱ型肺泡上皮显著增生;在晚期纤维化及实变的肺组织中,血管数目减少,管腔增大,分布分散,失去肺泡壁的结构轮廓。结论 SARS肺部病变具有血管反应、渗出、增生及纤维化等特点,其中巨噬细胞渗出可能在发病过程中起关键作用。

Immunohistochemical investigation of lungs with severe acute respiratory syndrome

OBJECTIVE: To investigate the roles of different cells in the pulmonary lesions in the severe acute respiratory syndrome (SARS) patients. METHODS: The monoclonal antibodies of CD8, CD20, CD34, LCA, CD56, CD68, and AE1/AE3 are used to demonstrate the different cells in the lung specimens of SARS patients in order to study the patterns of cell responses in this new disease. Meanwhile the HE stained slides were also carefully studied to compare with the results of immunohistochemical staining. RESULTS: The number of capillaries increased and the capillaries clearly outlined the contour of alveolar wall from beginning to early stage of organization, the number of lymphocytes decreased sharply while the number of macrophage remarkably increased, together with proliferation of type II pneumocytes. The numbers of blood vessels decreased in the fibrotic and consolidated lung tissue, and the vessel cavities enlarged, losing the normal contour of alveolar septa. CONCLUSIONS: The lesions in the lung from SARS patients are consisted of the tissue reaction to the inflammatory injury, including extensive exudation, capillary proliferation, fibrosis, and obvious infiltration of macrophages which may play a key role in the pathogenesis of pulmonary lesions of SARS.