SARS患者脾树突状细胞和巨噬细胞的免疫组织化学观察

目的 对严重急性呼吸综合征(SARS)患者脾树突状细胞、巨噬细胞数量和巨噬细胞大小进行定量分析,为SARS的病理变化和发病机制的探讨提供证据.方法 通过免疫组织化学技术对6例SARS死亡患者脾和6例意外死亡者正常脾S-100 、CD68 、 HLA-DR 、CD83 细胞的分布进行观察,并采用图像分析系统对阳性细胞数量或体积进行分析.结果 SARS死亡患者脾内白髓中S-100 树突状细胞数较正常平均减少80.49%,有的甚至完全消失;脾红髓中CD68 巨噬细胞数量较正常平均减少39.48%,体积是正常平均值的2.21倍.脾白髓中HLA-DR 抗原呈递细胞明显减少.SARS死亡患者脾与正常脾中均无CD83 成熟树突状细胞.结论 SARS患者免疫系统中抗原呈递系统遭到严重破坏,支持SARS是一种病毒性免疫缺陷病.SARS病毒不能引发树突状细胞成熟.巨噬细胞的体积增大处于激活状态,提示巨噬细胞在SARS发病机制中起一定作用.

THE IMMUNOHISTOCHEMICAL OBSERVATION OF DENDRITIC CELLS AND MACROPHAGES IN THE SPLEENS OF SARS PATIENTS

Objective To analyse the number of dendritic cells and macrophages and the size of macrophages in the spleen of SARS patients so as to provide evident for the study of pathology and pathogenesis of SARS. Methods Immunohistochemical method with four specific antibodies(S-100,CD68,HLA-DR,CD83) were used to detect the dendritic cells and macrophages in the spleens of six dead patients of SARS and six accidental deaths as the controls,The number or the size of these positive cells was analysed with image analysis system. Results In the spleens of SARS patients,the number of S-100~ dendritic cells in the white pulp was reduced by 80.4% on average,and even disappeard.The number of CD68~ macrophages in the red pulp was reduced by 39.48% in SARS spleens,and the average size of individual macrophages was increased by 2.21 times.HLA-DR~ antigen presenting cells(APC) reduced remarkably in the SARS spleen white pulp.CD83~ mature dendritic cells did not exist in either SARS spleens or the control spleens.Conclusion The function of antigen presentation had been damaged severely,which supports that SARS should be categorized as a viral immune deficiency disease.SARS virus doesn't induce the maturation of DC.The increase in the size of macrophages indicated that they were in an activated state and may play a role in the pathogenesis of SARS.