合成多肽对结核分枝杆菌的胞内抑制作用

摘要

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/mL。2号肽与细胞THP-1作用时，浓度为1200μg/mL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 H37Rv. The minimum inhibition concentration(MIC)of the synthetic polypeptide on H37Rv 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 H37Rv. Results were as below:All 4 screened peptides had bacteriostatic effect,the MIC of peptide-2 was 200 mg/mL. When the peptides-2 interacted with THP-1 cells,the cytotoxicity emerged at the concentration of 1200 mg/mL,meaning that there was no significant difference from INH’s cytotoxicity. For intracellular H37Rv,the anti-tuberculosis effects of peptide-2 presented time-and dose-dependent effect,the H37Rv 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.