Björkholm B, Zhukhovitsky V, Löfman C, Hultén K, Enroth H, Block M, Rigo R, Falk P, Engstrand L
Department of Clinical Microbiology, University Hospital, Uppsala, Sweden.
Helicobacter. 2000 Sep;5(3):148-54. doi: 10.1046/j.1523-5378.2000.00023.x.
Intracellular location of Helicobacter pylori in human gastric epithelial cells has been observed in biopsies. Whether this reflects an ability to invade host cells and establish an intracellular niche remains to be determined.
The interactions between a clinical isolate of H. pylori and primary cell cultures from human gastric epithelium or the human epithelial cell line HEp-2 were monitored using time-lapse photography. This technique allows studies of the dynamics of host-microbial interactions.
H. pylori cells readily approached and established close contacts with epithelial cells followed by uptake of the bacteria into the cellular cytoplasm. Entry into epithelial cells was achieved through an active process of bacterial motility and penetration of the cell membranes. In conventional invasion assays using HEp-2 cells, an increased internalization in a strain producing the vacuolating cytotoxin was observed, compared to the isogenic VacA knockout mutant.
Invasion of gastric epithelium represents a hitherto unappreciated trait of H. pylori that could contribute to the bacterium's ability to establish persistent infection that evades the mucosal immune defense and sometimes also antimicrobial therapy. A small number of bacterial cells with a transient intracellular habitat could serve as a seeder population, providing a backup for a constantly challenged and fluctuating luminal population.
在活检中已观察到幽门螺杆菌在人胃上皮细胞内的定位。这是否反映了其侵入宿主细胞并建立细胞内生态位的能力仍有待确定。
使用延时摄影监测幽门螺杆菌临床分离株与人胃上皮原代细胞培养物或人上皮细胞系HEp - 2之间的相互作用。该技术可用于研究宿主 - 微生物相互作用的动态过程。
幽门螺杆菌细胞很容易接近上皮细胞并与之建立紧密接触，随后细菌被摄取到细胞质中。细菌通过主动运动和穿透细胞膜进入上皮细胞。在使用HEp - 2细胞的传统侵袭试验中，与同基因VacA基因敲除突变体相比，观察到产生空泡细胞毒素的菌株内化增加。
胃上皮细胞的侵袭是幽门螺杆菌迄今未被认识的一种特性，这可能有助于该细菌建立持续感染的能力，从而逃避黏膜免疫防御，有时还能逃避抗菌治疗。少数具有短暂细胞内生存环境的细菌细胞可作为种子菌群，为不断受到挑战且波动的管腔菌群提供后备支持。
