【摘要】 目的运用实时细胞分析(RTCA)法和MTT法检测干酪乳杆菌(L.casei)、肠出血性大肠杆菌(EHEC)的细胞毒性,并比较两者优缺点。方法将L.casei及EHEC的菌液、菌体裂解液(MOI=200)以及上清液(25%)感染HT-29和LoVo细胞,经RTCA法和MTT法观察细菌对细胞的校正细胞指数(NCI)及细胞活力的影响。结果 RTCA法与MTT法结果一致,L.casei的活菌、菌体裂解液对HT-29细胞和LoVo细胞无明显毒性。EHEC的活菌对HT-29细胞和LoVo细胞有明显毒性,其菌体裂解液对HT-29细胞有明显毒性、对LoVo细胞无明显毒性。在上清液实验中,RTCA法检测出L.casei和EHEC对HT-29细胞无明显毒性,而LoVo细胞受培养基影响未能正确反映出上清液细胞毒性结果。结论与MTT法相比,RTCA法更适于细菌细胞毒性检测,但应在实验前选择合适的细胞系及种植浓度,建议在选用RTCA法检测细胞毒性时选择两种或两种以上细胞系,多方验证以避免漏检。更多还原

【Abstract】 Objective To detect the cytotoxicity of Lactobacillus casei and Enterohemorrhagic Escherichia coli by realtime cellular analysis(RTCA)and MTT methods,and compare their advantages and disadvantages. Methods HT-29 and LoVo cells were infected with live bacteria,cell lysate(MOI=200)and supernatant(25%)of L.casei and EHEC. The cell viability or normalized cell index was determined by RTCA and MTT methods. Results Live bacteria and cell lysate of L.casei were safe to HT-29 and LoVo cells. Live bacteria of EHEC showed obvious toxicity to HT-29 and LoVo cells.Cell lysate of EHEC was toxic to HT-29,but safe to LoVo cells. In the supernatant experiment,RTCA method showed that L.casei and EHEC had no obvious toxicity to HT-29 cells,while LoVo cells were affected by the medium and could not correctly reflect the supernatant cytotoxicity results. Conclusion RTCA works better for detection of bacteria cytotoxicity than MTT method.更多还原