Hechemy K E, Samsonoff W A, Harris H L, McKee M
Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201-0509.
J Med Microbiol. 1992 Apr;36(4):229-38. doi: 10.1099/00222615-36-4-229.
Adherence to and entry of the parasite into the host is one of the essential elements of microbial pathogenicity. We investigated the adherence to and entry into primate kidney epithelial (Vero) cells of Borrelia burgdorferi by radiolabelling techniques, immunofluorescence and electronmicroscopy. The attachment to and subsequent entry of both untreated and heat (50 degrees C)-treated B. burgdorferi into Vero cells occurred at cell-surface sites associated with aggregated coated pits. In contrast, there was minimal attachment of spirochaetes heated at 60 degrees C. Radiometric studies showed that, with untreated cells, there was incorporation of both 14C-glucose-1-phosphate and 14C-thymidine, whereas with the 50 degrees C-treated spirochaetes only glucose-1-phosphate was incorporated, and with the 60 degrees C-treated spirochates neither radionuclide was incorporated. Spirochaetes heated at 50 degrees C or 60 degrees C did not grow at 35 degrees C in culture medium. These results suggest that the presence of certain metabolic activities of the spirochaete but not viability (ability to grow) are necessary for the attachment process. After entry of untreated B. burgdorferi, most of the spirochaetes were either free in the cytoplasm or tightly bound to the host membrane. In contrast, 50 degrees C-treated spirochaetes remained bound to host membrane in large phagosome-like vesicles.
寄生虫对宿主的黏附及进入是微生物致病性的关键要素之一。我们运用放射性标记技术、免疫荧光及电子显微镜，研究了伯氏疏螺旋体对灵长类肾上皮（Vero）细胞的黏附及进入情况。未处理的和经热（50℃）处理的伯氏疏螺旋体对Vero细胞的黏附及随后的进入均发生在与聚集的包被小窝相关的细胞表面位点。相比之下，60℃加热的螺旋体黏附极少。放射性研究表明，对于未处理的细胞，14C - 葡萄糖 - 1 - 磷酸和14C - 胸苷均有掺入，而对于50℃处理的螺旋体，仅葡萄糖 - 1 - 磷酸有掺入，60℃处理的螺旋体则两种放射性核素均未掺入。50℃或60℃加热的螺旋体在35℃的培养基中均不生长。这些结果表明，螺旋体的某些代谢活性而非生存能力（生长能力）对于黏附过程是必要的。未处理的伯氏疏螺旋体进入后，大多数螺旋体要么游离于细胞质中，要么紧密结合于宿主膜。相比之下，50℃处理的螺旋体则以类似吞噬体的大囊泡形式与宿主膜结合。
