Characterization of rickettsial attachment to host cells by flow cytometry.
Characterization of rickettsial attachment to host cells by flow cytometry.
复制标题
通过流式细胞术表征立克次体与宿主细胞的附着。
DOI：
10.1128/iai.60.5.2030-2035.1992
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发表时间：
1992
影响因子：
3.1
通讯作者：
Walker,DH
中科院分区：
文献类型：
--
作者：
Li,H;Walker,DH
通过流式细胞仪检测立克次体与宿主细胞不同处理后与宿主细胞结合的数量变化，研究了立克次体附着的机制。当用立克次体特异性单抗检测时，立克次体-宿主细胞组合的宿主细胞表面荧光强度增加，证明了康氏立克次体与宿主细胞的时间依赖性结合。由于立克次体与细胞表面的结合，70%以上的宿主细胞在孵育10min后荧光强度超过阈值，最大结合荧光强度出现在20min。结合动力学与立克次体的剂量相关。当宿主细胞或立克次体分别用1%多聚甲醛作用30min或0.25%胰酶作用5min或15min时，立克次体与宿主细胞的结合力显著降低。在56摄氏度下加热15分钟的立克次体失去了80%以上的附着于宿主细胞的能力。里氏杆菌是一种与康氏杆菌关系密切的生物，它竞争性地抑制康氏杆菌的附着(当混合数量相等时，抑制率为51%)。这些结果表明立克次体结合结构是胰酶和热敏性的，很可能是表面蛋白。
The mechanisms of rickettsial attachment have been studied by measuring quantitative changes in rickettsial binding to host cells by flow cytometry after different treatments of the rickettsiae and host cells. Time-dependent binding of Rickettsia conorii to host cells was demonstrated by the increasing intensity of host cell surface fluorescence of rickettsia-host cell combinations when examined with a rickettsia-specific monoclonal antibody. More than 70% of host cells had intensity of fluorescence above the threshold value after 10 min of incubation, owing to rickettsiae bound to the cell surface, and the greatest fluorescence intensity indicative of binding occurred at 20 min. The binding kinetics was rickettsial dose dependent. The binding of rickettsiae to host cells was greatly decreased when host cells or rickettsiae were treated with 1% paraformaldehyde for 30 min or 0.25% trypsin for 5 or 15 min, respectively. Rickettsiae that were heated at 56 degrees C for 15 min lost more than 80% of their ability to attach to host cells. R. rickettsii, an organism closely related to R. conorii, competitively inhibited the attachment of R. conorii (51% inhibition when mixed in equal numbers). These results indicate that the rickettsial binding structures are trypsin and heat sensitive and likely to be surface proteins.