Role of salivary protease activity in adherence of gram-negative bacilli to mammalian buccal epithelial cells in vivo.
Role of salivary protease activity in adherence of gram-negative bacilli to mammalian buccal epithelial cells in vivo.
复制标题
唾液蛋白酶活性在革兰氏阴性杆菌与哺乳动物口腔上皮细胞体内粘附中的作用。
DOI：
10.1172/jci110395
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Bass,JA
中科院分区：
文献类型：
--
作者：
Woods,DE;Straus,DC;JohansonJr,WG;Bass,JA
严重的疾病伴随着对革兰氏阴性杆菌在呼吸道定植的明显易感性增加，并且在体外培养期间，这种附着在局部上皮细胞上的有机体的数量增加。正常受试者的胰蛋白酶化细胞引起类似的细菌粘附性增加。我们在体外研究了细菌对口腔细胞的粘附，用纤维蛋白平板技术研究了上呼吸道分泌物的蛋白酶活性，用直接放射免疫结合法研究了口腔细胞表面纤维连接蛋白的数量。10例严重急性呼吸衰竭患者口腔细胞黏附菌和分泌物蛋白酶活性均较对照组升高，细胞表面纤维连接蛋白降低；所有患者体内均有革兰氏阴性杆菌定植。这些变化是持续的，80%的患者死亡。对8例接受冠状动脉搭桥手术的患者进行了系列测定。手术后，蛋白酶活性和细菌粘附增加，细胞表面纤维连接蛋白下降；38%的冠状动脉搭桥术患者变成了殖民地。在这些无并发症的患者中，观察到的变化是短暂的，大部分在术后第三天恢复正常。在重大疾病发生后，分泌物蛋白酶活性的增加和上皮细胞表面的改变（由口腔细胞表面纤维连接蛋白的丧失所反映）迅速发生，似乎是杆菌细胞粘附增强和上呼吸道定植的基础。这些发现提示了预防院内肺炎的新途径。图片
Serious illness is accompanied by markedly increased susceptibility to colonization of the respiratory tract by gram-negative bacilli and an increase in the number of such organisms which adhere to regional epithelial cells during incubation in vitro. Trypsinization of cells from normal subjects causes a similar increase in bacillary adherence. We studied bacillary adherence to buccal cells in vitro, protease activity of upper respiratory secretions with a fibrin plate technique, and the amount of fibronectin on the surface of buccal cells with a direct radioimmunobinding assay. Among 10 patients seriously ill with acute respiratory failure bacillary adherence to buccal cells and protease activity in secretions were increased compared with controls and cell-surface fibronectin was decreased; all patients were colonized in vivo with gram-negative bacilli. These changes were persistent and 80% of the patients died. Serial determinations were made in eight patients undergoing coronary artery bypass surgery. Following surgery, protease activity and bacillary adherence increased and cell-surface fibronectin decreased; 38% of coronary artery bypass patients became colonized. In these uncomplicated patients the changes observed were transient, largely returning to normal by the third postoperative day. Increased protease activity of secretions and alterations in epithelial cell surfaces as reflected by loss of buccal cell-surface fibronectin occur swiftly after major illness and appear to underlie enhanced cell adherence of bacilli and colonization of the upper respiratory tract. These findings suggest new approaches to the prevention of nosocomial pneumonia.Images