【摘要】 目的研究在一种快速、特异的mPCR方法在检出福氏志贺菌的同时对其毒力进行监测。方法选取福氏志贺菌三种毒力基因ipaH,ial,set1B作为扩增目标,在同一mPCR体系中对86株福氏志贺菌临床分离株进行了检测,并选取12株进行了噬斑形成试验,观察了扩增产物不同的福氏志贺菌对Hela细胞的毒力作用。结果86株福氏志贺菌临床分离株均检测到ipaH基因,阳性率为100%;45株检测到ial基因,阳性率为52%;69株检测到set1B基因,阳性率为80%。噬斑形成试验证明,mPCR结果不同的菌株对Hela细胞的感染能力存在明显差异。结论应用上述mPCR体系在检出福氏志贺菌的同时能够对菌株的毒力进行初步判别,对于临床诊断及治疗具有重要意义。更多还原

【Abstract】 To develop a rapid and specific multiplex PCR assay for the detection of Shigella flexneri from clinical isolates,three virulence genes of Sh flexneri,ipaH,ial and set1B were selected for the targets of amplification,and 86 strains of Sh flexneri from clinical isolates were studied by multiplex PCR with 3 pairs of primers based on the gene sequences of these virulence genes.The virulence of amplification products of 12 strains to HeLa cells was determined by plaque formation test.It was found that the ipaH gene was detected in all these 86 strains of Sh flexneri isolates with a 100% detection rate,while the ial gene and set1B gene were detected in 45 and 69 strains of isolates with the detection rate of 52.3% and 80 2% respectively.The multiplex PCR for other enterobacteriae,such as S.typhi,Serratia oderifer and E.coli 25922,showed negative results.As demonstrated by the plaque formation test,the numbers of plaque formation on HeLa cells were more than 1000 plagues/ml for 9 strains of high virulence,but less than 50 plagues/ml for 3 strains of low virulence.It is evident this multiplex PCR assay appears to be reproducible,sensitive and specific and can be used to identify the virulent strains of Sh flexneri from clinical isolates.更多还原