活化NK细胞抗结核分枝杆菌感染的实验研究

Research on the role of activated NK cells in combating infection with Mycobacterium tuberculosis

目的探讨活化的NK细胞的抗结核分枝杆菌作用,为建立一种新型安全的以NK细胞源性外泌体(exosome)为基础的抗结核免疫疗法提供基础。方法将从外周血分离纯化的NK细胞活化后直接作用于结核分枝杆菌(Mtb)感染的巨噬细胞,通过观察细胞形态变化,细菌抑菌率,乳酸脱氢酶(LDH)活性等评价NK细胞的抗Mtb作用。结果流式细胞术检测活化NK细胞纯度为95%;Mtb感染后的Ana-1巨噬细胞形态成多形性;Mtb感染的巨噬细胞受活化NK细胞作用6、12、24h的抑菌率分别为(39.1±4.2)%、(73.9±6.4)%和(91.3±5.7)%,其中以作用24h的抑制率最好;LDH释放率与活化NK细胞作用时间成正比。结论 NK细胞在体外有抗Mtb的作用,为研究更为安全的NK源性exosome的抗Mtb作用奠定了基础。

Objective To investigate whether activated NK cells act against Mycobacterium tuberculosis and to provide a basis for further exploration of a new safe anti-tuberculosis immunotherapy based on NK cell-derived exosomes.Methods Macrophages infected with M.tuberculosis were treated with NK cells isolated from peripheral blood at different times.The action of NK cells against M.tuberculosis was studied by observing changes in cell morphology,the rate of bacterial inhibition,and the level of LDH activity.Results Flow cytometry indicated that the purity of activated NK cells was 95%.After infection with M.tuberculosis,Ana-1 macrophages had a pleomorphic morphology.Macrophages infected with M.tuberculosis were inhibited by activated NK cells at a rate of(39.1±4.2)% at 6 h,(73.9±6.4)% at 12 h,and(91.3±5.7)% at 24 h.The rate of inhibition was highest at 24 h.The rate of LDH release was proportional to the duration of activation of NK cells.Conclusion NK cells act against M.tuberculosis in vitro.This finding may provide a basis for further study of the anti-M.tuberculosis action of NK-derived exosomes.