应用基因探针检测志贺氏菌属毒力株的研究

Application of Gene Probe In Detection of Shigella Virulent Strains

本文应用α^(-32)P标记的福氏5型140Md侵袭性质粒之ECORI 17kb基因探针杂交、侵袭性质粒分析和豚鼠角膜炎试验对志贺氏菌属的毒力株进行了研究。结果表明,健康人菌株探针杂交的弱阳性率(47.18％)和阴性率(5.33％)均高于病人菌株(8.27％,1.38％),(u=14.03 p<0.01;u=3.644p<0.01),提示,无症状带菌者多因弱毒株或无毒株感染所致。探针杂交的阴性菌株和90％以上的弱阳性菌株均属于3a、1b、2a、4a和DⅡ5个血清型,表明这些血清型中的弱毒株、无毒株或丧失质粒的频率较高。

To detect the virulent strains of shigella, α-^(32)P labelled ECORI 17kb gene probe of 140Md invasive plasmid of S. flexneri 5, as well as invasive plas- mid analysis and sereny test were emplcyed in this study. The result showed that the probe hybr- idization weak positive rate (47.18%) and negative rate (5.33%) of the isolated from health population were high than that of isolated from patients (8.27% and 1.38% respectively), (U= 14.03 P<0.01; U= 3.644 P<0.01), this indicated that the asystematio carries are resulted from the infection of weak virulent strains or avirulent strains. The probe hybridization negative strains and, more than 90% of the probe hybridization weak positive strains belong to 3a, 1b, 2a, 4a and DⅡ 5 serotypes. This indicated that there was a high frequency of aviru- lent strains, weak virulent strains and loss of pla- smids among those serotypes.