合成多肽对结核分枝杆菌的胞内抑制作用

Intracellular Inhibitory Effect of Synthetic Peptide on Mycobacterium tuberculosis

评价合成多肽对人白血病单核巨噬细胞THP-1的毒性和对结核分枝杆菌H37Rv的胞内抑菌作用。通过多肽的不同给药浓度,确定多肽对结核分枝杆菌的最小抑菌浓度(MIC),利用流式细胞术方法和MTT法检测2号肽对细胞THP-1的毒性作用,同时采用CFU方法检测其对H37Rv菌株的胞内抑菌作用。筛选的4条多肽均有抑菌作用,其中2号肽的最小抑菌浓度(MIC)最小,为200μg/m L。2号肽与细胞THP-1作用时,浓度为1 200μg/m L时表现出细胞毒性,与INH细胞毒性无显著差别。对于胞内H37Rv,2号肽抗结核作用具有时间和剂量依赖效应,随给药时间和剂量的增加H37Rv菌落数明显下降。2号肽不仅对巨噬细胞THP-1的毒性小,而且具有较好的抗胞内结核分枝杆菌活性,是一种潜在的抗结核新型药物。

This work is to evaluate the toxicity of the synthetic peptides on mononuclear macrophage THP-1 of human leukemia and the intracellular bacteriostatic effect on Mycobacterium tuberculosis H37 Rv. The minimum inhibition concentration（MIC）of the synthetic polypeptide on H37 Rv was determined through the different drug concentrations of poly-peptides. Then,the toxic effects of peptide-2 on THP-1 cells were detected using flow cytometry method and MTT method. The colony-forming unit（CFU）method was used for detecting intracellular bacteriostatic effect of peptide-2 on H37 Rv. Results were as below ：All 4 screened peptides had bacteriostatic effect,the MIC of peptide-2 was 200 mg/m L. When the peptides-2 interacted with THP-1 cells,the cytotoxicity emerged at the concentration of 1200 mg/m L,meaning that there was no significant difference from INH＇s cytotoxicity. For intracellular H37 Rv,the anti-tuberculosis effects of peptide-2 presented time- and dose- dependent effect,the H37 Rv colony count was obviously decreased with the increase of the time and dose. In conclusion,not only has the peptide-2 small toxicity to the macrophage THP-1,but also solid intracellular anti-M. tuberculosis effect,and it can be a new and potential anti-tuberculosis drug.