Onai H, Kudo S
Respiratory Organ and Cardiovascular Disease Center, Ohsato-gun 360-0102, Saitama, Japan.
Eur J Clin Invest. 2001 Mar;31(3):272-80. doi: 10.1046/j.1365-2362.2001.00784.x.
We examined whether the lung injury produced in rats by intraperitoneal injection of the superantigen, staphylococcal enterotoxin B (SEB), could be inhibited by intravenous preadministration of human urinary trypsin inhibitor (UTI), which exhibits multipotent inhibitory effects on serine proteinases such as plasmin, chymotrypsin, or human leukocyte elastase or cathepsin G, since preliminary experiments showed the ability of UTI to bind lipopolysaccharides and bacterial toxins. For ligand blotting analysis, four kinds of toxins were run on a slab gel and the binding of UTI to the toxins was visualized by immunoblotting. Lung tissue from 26 rats was used for immunohistochemistry using a mouse antirat CD 45 mAb and an antirat macrophage mAb. Lung tissue from 31 rats was used for measurement of myeloperoxidase activity before and after intraperitoneal injection of SEB, after infusion of PBS, UTI, PBS-SEB or UTI-SEB combination. Ten of the 26 rats described above were used for electron microscopy. Rat sera were used for measurement of TNF-alpha. Statistical analysis was performed using the Mann-Whitney U-test. Intraperitoneal injection of SEB caused an increase in the number of punctate areas of haemorrhage on the surface of the lung with time, and histological examination revealed lung injuries with different extents, vasculitis where inflammatory cells were concentrated, and infiltration of numbers of eosinophils into the alveolar septa. However, preadministration of UTI for rats markedly attenuated lung injury and vasculitis induced by intraperitoneal injection of SEB. This revealed, from a marked reduction in the number of inflammatory cells and the extent of injury, a marked inhibition of serum TNF-alpha production and reduction of myeloperoxidase content of rat lungs compared to controls. UTI may have defensive effects to infection by suppressing the early responses of stimulated cells to activated stimulus such as SEB as well as the release of stimulant-mediated cytokines via trapping of bacterial toxins.
我们研究了腹腔注射超抗原——葡萄球菌肠毒素B（SEB）所致的大鼠肺损伤，是否能通过静脉预先给予人尿胰蛋白酶抑制剂（UTI）来抑制。UTI对诸如纤溶酶、胰凝乳蛋白酶、人白细胞弹性蛋白酶或组织蛋白酶G等丝氨酸蛋白酶具有多种抑制作用，因为初步实验显示UTI具有结合脂多糖和细菌毒素的能力。为进行配体印迹分析，将四种毒素在平板凝胶上进行电泳，通过免疫印迹观察UTI与毒素的结合情况。26只大鼠的肺组织用于免疫组织化学，使用小鼠抗大鼠CD45单克隆抗体和抗大鼠巨噬细胞单克隆抗体。31只大鼠的肺组织用于在腹腔注射SEB前及注射后、输注PBS、UTI、PBS-SEB或UTI-SEB组合后测定髓过氧化物酶活性。上述26只大鼠中的10只用于电子显微镜检查。大鼠血清用于测定肿瘤坏死因子-α（TNF-α）。采用曼-惠特尼U检验进行统计学分析。腹腔注射SEB导致肺表面点状出血区域数量随时间增加，组织学检查显示有不同程度的肺损伤、炎症细胞聚集的血管炎以及大量嗜酸性粒细胞浸润到肺泡间隔。然而，给大鼠预先给予UTI可显著减轻腹腔注射SEB所致的肺损伤和血管炎。与对照组相比，这从炎症细胞数量和损伤程度的显著减少、血清TNF-α产生的显著抑制以及大鼠肺组织髓过氧化物酶含量的降低中得以体现。UTI可能通过抑制受刺激细胞对诸如SEB等激活刺激的早期反应以及通过捕获细菌毒素来抑制刺激介导的细胞因子释放，从而对感染具有防御作用。
