体液免疫在SARS发病机制中的作用

目的探讨体液免疫在严重急性呼吸综合征(severe acute respiratory syndrome,SARS)发病机制中作用.方法应用光镜、电镜观察SARS尸检和1例肺穿刺活检组织的病理形态变化;用免疫组化及组织化学方法检测组织自身抗体及免疫复合物.结果SARS患者肺组织呈弥漫性重度损伤,肺气-血屏障结构严重破坏,血管内皮细胞损伤;多脏器血管纤维素样坏死,广泛免疫器官损伤及多个器官病变组织存在大量的自身抗体和免疫复合物.电镜下见血管基膜、肾小球系膜区电子致密物沉积.结论SARS的组织损伤不仅是病毒直接损伤组织,而且伴有机体过度免疫反应,形成免疫复合物型变态反应,提示体液免疫在组织损伤中起重要作用.

Study on mechanisms of humoral immunity in SARS

Objective To explore the roles of humoral immunity in severe acute respiratory syndrome (SARS). Methods The pathological changes in the SARS autopsy case and a case of lung puncture were observed by light microscopy and electron microscopy. The autoantibody and immune complexes in the sample tissues were detected by immunohistochemical staining and histochemical staining. Results There were severely diffusive damages in the lungs. The endothelial cells in blood were injured. Fibrinoid necroses of blood vessels were observed in several organs and injury of immune organs and massive autoantibody and immune complexes were found in pathologically changed tissues. Electron dense deposits were observed in the basement membrane of blood vessels and mesangial matrix of glomerulus by electron microscopy. Conclusion The SARS viruses not only cause direct damages to the tissues but also lead to immune complex mediated hypersensitivity which in turn gives rise to a large number of tissue lesions. This indicates that the humoral immunity plays an important role in the process of organ damages.