EFFECT OF MOTILITY AND CHEMOTAXIS ON THE INVASION OF SALMONELLA-TYPHIMURIUM INTO HELA-CELLS
EFFECT OF MOTILITY AND CHEMOTAXIS ON THE INVASION OF SALMONELLA-TYPHIMURIUM INTO HELA-CELLS
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DOI：
10.1016/0882-4010(90)90039-s
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发表时间：
1990-07-01
影响因子：
3.8
通讯作者：
PECHERE, JC
中科院分区：
文献类型：
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作者：
KHORAMIANFALSAFI, T;HARAYAMA, S;PECHERE, JC
鼠伤寒沙门氏菌菌株LT2能够在体外侵入HeLa细胞。通过两种方法检测细菌的运动性和趋化性对细胞侵袭的影响：(1)常规入侵实验，将HeLa细胞单层水平放置在塑料孔底部；(2)垂直实验，将HeLa细胞单层垂直放置在塑料瓶的一面。在这两个实验中，野生型菌株的入侵率高于等基因非运动突变体。无鞭毛突变体的入侵率与有鞭毛但不活动突变体的入侵率无显著差异。这些观察结果表明，运动本身通过增加沙门氏菌和HeLa细胞之间相遇的机会来增加细菌入侵的速度。在常规实验中，平滑游动的非趋化突变体的入侵率是野生型菌株的10倍，而在垂直实验中，其入侵率与野生型菌株大致相当。这一结果表明，在常规实验中，野生型细菌向HeLa细胞的迁移受到其趋化反应的阻碍。静止的非趋化突变体表现出介于野生型和非运动型菌株之间的入侵率，这可能是因为它们的净迁移速度居中。
Salmonella typhimurium strain LT2 is able to invade HeLa cells in vitro. The effect of the motility and chemotaxis of the bacteria on cell invasion were examined by two methods: (1) conventional invasion assays where the HeLa cell monolayers were placed horizontally at the bottom of plastic wells and (2) vertical assays where the HeLa cell monolayer attached to one face of plastic bottles was placed vertically. In both assays, the invasion rate of the wild-type strain was higher than that in isogenic non-motile mutants. There was no significant difference between the invasion rate of non-flagellated mutants and that of a flagellated but non-motile mutant. These observations indicated that the motility per se increases the rate of the bacterial invasion by increasing the chance of encounter between Salmonella and the HeLa cells. Smooth-swimming non-chemotactic mutants exhibited 10 times higher invasion rates than the wild-type strain in convetional assays but their invasion rates in vertical assays were approximately equal to that of the wild-type strain. This result indicated that in the conventional assays, the migration of the wild-type bacteria towards the HeLa cells was hampered by their chemotactic responses. Tumbly non-chemotactic mutants exhibited invasion rates intermediate between the wild-type and non-motile strains presumably because of their intermediate net speeds of migration.