目的了解上海市单核细胞增生李斯特菌(Listeria monocytogenes,LM)食品和临床分离株的毒力特点、耐药性及其基因特征。方法采用试管凝集法对89株LM食品和临床分离株进行血清分型,采用聚合酶链反应(PCR)方法对LM中7个毒力基因进行检测,采用琼脂扩散(K-B)法对其进行药敏试验,采用脉冲场凝胶电泳法(PFGE)对89株LM分离株进行分型研究。结果血清分型结果显示1/2a和1/2c是LM优势血清型。只有4株LM食品分离株对四环素显示耐药,其余均为敏感。89株LM食品和临床分离株都含有7种毒力基因。89株食品和临床分离株经双酶切分型可得40条不同的条带,且1株临床菌株的PFGE分型显示其为食品分离株的亚型。结论上海市LM分离株的耐药性并不严重,但是其均为产毒株,且PFGE分型结果显示临床菌株与食品分离株之间有较近的亲缘关系,这提示上海市LM分离株对公共卫生具有潜在的危险,需要对其加强监测。 Objective To understand the virulence, drug resistance and gene characteristics of Shanghai food and clinical isolates of Listeria monocytogenes (LM). Methods 89 strains of LM food and clinical isolates were serotyped by the tube agglutination method. Seven virulence genes were detected by polymerase chain reaction (PCR) in the LM and were treated by KB method Sensitive test, the use of pulsed-field gel electrophoresis (PFGE) 89 strains of LM were typed. Results Serotyping results showed that 1 / 2a and 1 / 2c were predominant serotypes of LM. Only four LM food isolates showed resistance to tetracycline and the rest were sensitive. 89 strains of LM food and clinical isolates contain 7 virulence genes. Forty-eight different bands were obtained from 89 strains of food and clinical isolates by double enzyme digestion, and PFGE typing of one clinical strain showed that it was a subtype of the food isolate. CONCLUSION: The drug resistance of LM isolates in Shanghai is not serious, but they are all toxigenic strains. PFGE typing results show that there is a close genetic relationship between clinical isolates and food isolates, suggesting that LM strains There is a potential danger to public health that needs to be monitored.