中文摘要：

目的对严重急性呼吸综合征（SARS）患者肺组织中基质金属蛋白酶-9（MMP-9）、巨噬细胞（CD68^＋细胞）及弹性纤维进行定量分析，研究三者之间变化的关系，探讨MMP-9在SARS患者肺损伤修复中的作用机制和意义。方法通过免疫组织化学技术对6例SARS死亡患者肺和5例肺外伤患者手术切除的正常肺组织中MMP-9和CD68^＋细胞进行检测，Gomori醛品红法显示弹性纤维，应用Motic Advanced4．0图像分析系统进行定量分析，测定MMP-9的面密度、CD68^＋细胞的数量、弹性纤维的含量，并与正常对照组进行比较。结果SARS患者肺组织中MMP-9和CD68^＋细胞的数量均明显增加，而弹性纤维的含量明显减少，提示SARS患者肺组织中弹性纤维出现断裂。相关分析显示，SARS患者肺组织中MMP-9的面密度与CD68^＋细胞的数量呈正相关，与弹性纤维的含量呈负相关。结论SARS死亡患者肺组织中巨噬细胞的增加可引起MMP-9明显增加，后者可导致弹性纤维的降解，MMP-9在SARS患者肺损伤修复过程中可能起到桥梁作用。

英文摘要：

Objective To make a quantitative analysis of matrix metalloproteinase-9（MMP-9） in lung tissue of patients with severe acute respiratory syndrome（SARS） and alveolar macrophage（ CD68 positive cell） and elastic fiber, the change between them, the significance and probable molecular mechanism of MMP-9 in lung injury of SARS as well. Methods Immunohistochemical method with two specific antibodies （ MMP-9, CD68 ） was used to detect the their special antigens in lung tissues of six cases who died of SARS and five normal cases as the controls. Gomori aldehyde fuchsine staining method was used to explore the change of elastic fiber. Motic advanced 4.0 image analysis system was used to analyze those images. Results The expression of MMP-9 and the number of CD68 positive cells were up-regulated in the lung tissue of patients with SARS, but the amounts of elastic fiber were obviously less than those in the normal lung tissue and occurrence of rupture of elastic fiber. The correlate analysis designed the up-regulation expression of MMP-9 in the lung tissue of patients with SARS was positive correlation with the amount of CD68 positive cells but negative correlation with elastic fiber. Conclusions Alveolar macrophages in lung tissue of patients with SARS increased significantly. It caused the up-regulated expressions of MMP-9. MMP-9 led to a large-scale disruption of elastic fiber. The role of MMP-9 in the recovery of lung injury induced by SARS seemed to act as a bridge.