Finlay B B, Fry J, Rock E P, Falkow S
Department of Medical Microbiology, Stanford University School of Medicine, California 94305.
J Cell Sci Suppl. 1989;11:99-107. doi: 10.1242/jcs.1989.supplement_11.8.
Salmonella are intracellular parasites which enter their hosts by penetrating the intestinal epithelial barrier. We examined the interaction of S. choleraesuis and S. typhimurium with Madin Darby canine kidney (MDCK) and human larynx (HEp-2) epithelial cells to characterize bacterial adherence, invasion and penetration through epithelial monolayers. Epithelial cell microfilaments were required for bacterial internalization and surrounded the bacteria as they were internalized. The bacteria entered membrane-bound vacuoles inside epithelial cells where they replicated. When polarized MDCK cell monolayers were infected, we found that Salmonella could pass through this barrier and enter medium bathing the opposite surface, although most bacteria remained within the monolayer. Synthesis of several Salmonella proteins was induced by the presence of epithelial cell surfaces, and these proteins were required for bacterial adherence and invasion. This induction was stimulated by trypsin- and neuraminidase-sensitive structures on epithelial cells.
沙门氏菌是细胞内寄生虫，通过穿透肠道上皮屏障进入宿主。我们研究了猪霍乱沙门氏菌和鼠伤寒沙门氏菌与麦迪逊-达比犬肾（MDCK）和人喉（HEp-2）上皮细胞的相互作用，以表征细菌对上皮单层的黏附、侵袭和穿透。细菌内化需要上皮细胞微丝，并且在细菌内化时微丝围绕着它们。细菌进入上皮细胞内的膜结合液泡并在其中复制。当极化的MDCK细胞单层受到感染时，我们发现沙门氏菌可以穿过这一屏障并进入另一侧表面的培养液中，尽管大多数细菌仍留在单层内。上皮细胞表面的存在可诱导几种沙门氏菌蛋白的合成，这些蛋白是细菌黏附和侵袭所必需的。这种诱导受到上皮细胞上对胰蛋白酶和神经氨酸酶敏感的结构的刺激。
