Micots I, Augeron C, Laboisse C L, Muzeau F, Mégraud F
Laboratoire de Bactériologie-Enfants, Hôpital Pellegrin, Bordeaux, France.
J Clin Pathol. 1993 Mar;46(3):241-5. doi: 10.1136/jcp.46.3.241.
To determine whether Helicobacter pylori impairs the secretory function of mucous cells.
The mucus secreting human cell line CL. 16E, maintained as confluent monolayers on nitrocellulose filters, was infected with H pylori strain CIP 101260. After three hours of incubation with H pylori the monolayers were washed and reincubated with fresh culture medium for various time periods (24, 48, or 72 hours) before evaluating both the morphology and function of mucous cells. For morphological studies, epithelial monolayers were fixed in situ and processed for both standard histochemistry on paraffin wax sections, and electron microscopy. To measure mucins secreted from cultured cells, the cells were metabolically labelled with 3H-glucosamine. Undegraded mucins were quantitated as the radioactive glycoproteins blocked at the stacker gel interface after sodium dodecyl sulphate-polyacrylamide gel electrophoresis of the secretory glycoproteins.
Control cultures of CL. 16E cells grew on filters as homogeneous monolayers of polarised mucous cells secreting a visco-elastic gel of mucins at the apical surface. In infected monolayers H pylori was in close contact with the apical surface of mucous cells. Cell counts and histological evaluation of the monolayers did not reveal any significant deleterious effect of H pylori on the mucous cells. H pylori induced only a modest inhibition of baseline mucus secretion from CL. 16E cells, this inhibition being significant only at 24 hours. In contrast, the mucus secretory response to two agents that raise intracellular cAMP and calcium--forskolin and ionophore A23187--was strongly inhibited. The inhibitory effect of H pylori on the exocytotic response was not paralleled by an inhibition of glycoprotein synthesis.
Considering the fact that the exocytotic response to a variety of secretagogues constitutes the primary line of defence of the gastric mucosa in an emergency, it is suggested that H pylori exerts its deleterious effects by weakening this important physiological defence.
确定幽门螺杆菌是否会损害黏液细胞的分泌功能。
将在硝酸纤维素滤膜上维持为汇合单层的人黏液分泌细胞系CL. 16E用幽门螺杆菌菌株CIP 101260感染。在与幽门螺杆菌孵育三小时后，冲洗单层细胞，并用新鲜培养基再孵育不同时间段（24、48或72小时），然后评估黏液细胞的形态和功能。对于形态学研究，上皮单层原位固定，并进行石蜡切片的标准组织化学和电子显微镜检查。为了测量从培养细胞分泌的黏蛋白，用3H-葡糖胺对细胞进行代谢标记。未降解的黏蛋白通过对分泌糖蛋白进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳后，在堆积凝胶界面处被阻断的放射性糖蛋白进行定量。
CL. 16E细胞的对照培养物在滤膜上生长为极化黏液细胞的均匀单层，在顶端表面分泌黏蛋白的粘弹性凝胶。在感染的单层中，幽门螺杆菌与黏液细胞的顶端表面紧密接触。单层细胞的细胞计数和组织学评估未发现幽门螺杆菌对黏液细胞有任何明显的有害影响。幽门螺杆菌仅对CL. 16E细胞的基础黏液分泌有适度抑制，这种抑制仅在24小时时显著。相比之下，对两种升高细胞内cAMP和钙的试剂——福斯高林和离子载体A23187——的黏液分泌反应受到强烈抑制。幽门螺杆菌对胞吐反应的抑制作用与糖蛋白合成的抑制作用不平行。
鉴于对多种促分泌剂的胞吐反应是胃黏膜在紧急情况下的主要防御线，提示幽门螺杆菌通过削弱这一重要的生理防御发挥其有害作用。
