观察T4噬菌体对M2型巨噬细胞向M1型再极化的诱导作用，并检测再极化的M1型巨噬细胞诱导小鼠Lewis肺癌细胞凋亡和抑制其侵袭的作用效果。方法：小鼠巨噬细胞RAW264.7经白细胞介素-4（IL-4）诱导为替代性活化巨噬细胞（M2型），以T4噬菌体对M2型巨噬细胞再极化诱导；Real-time PCR检测IL-4诱导极化及T4噬菌体再极化后巨噬细胞中〖STBX〗IL-12、TNF-α、Arg-1、TGF-β、IL-10和iNOS〖STBZ〗基因mRNA的变化，Western blotting检测巨噬细胞内iNOS和Arg-1蛋白表达变化，ELISA法检测巨噬细胞培养上清中IL-10和IL-12的含量；流式细胞术和Transwell法分别检测T4噬菌体再极化巨噬细胞诱导小鼠Lewis肺癌细胞凋亡和抑制其侵袭的作用效果。结果：RAW264.7细胞经IL-4处理后被诱导成为M2型巨噬细胞，其〖STBX〗iNOS和IL-12〖STBZ〗 mRNA表达分别下降为对照组的1/2.5和1/6.2，而〖STBX〗Arg-1和IL-10〖STBZ〗 mRNA表达分别增加了161.2和120.3倍。M2型巨噬细胞经野生型和突变型T4噬菌体处理后，〖STBX〗IL-12、TNF-α、iNOS〖STBZ〗在mRNA和蛋白水平均明显逆转上调，〖STBX〗IL-10、TGF-β、Arg-1〖STBZ〗则明显逆转下调，呈现M1型特征；其中突变型T4噬菌体的诱导作用显著强于野生型。野生型和突变型T4噬菌体诱导M1再极化的巨噬细胞致小鼠Lewis肺癌细胞的凋亡率较M2型巨噬细胞显著增高[（35.3±2.44）%、（39.1±208）% vs （4.68±0.56）%；均P<0.01）]，同时，显著抑制了肺癌细胞的侵袭能力[侵袭细胞数：（43.8±7.51）、（23.2±4.33）个 vs （1775±12.33）个；均P<0.01]。结论：T4噬菌体能够诱导M2型巨噬细胞向M1型再极化，并增强巨噬细胞诱导肿瘤细胞凋亡和抑制肿瘤细胞侵袭的能力。

To analyse T4 phage-induced M1 re-polarization of tumor-associated M2 type macrophages, and to evaluate the ability of re-polarized M1 macrophages on apoptosis and metastasis of mouse Lewis lung cancer cells in vitro. Methods: Mouse macrophage RAW264.7 cells were induced into M2 type macrophages by interleukin-4 (IL-4), which were subsequently induced to re-polarize with T4-bacteriophage. In both IL-4-induced M2 macrophages and T4 repolariezed-macrophages, mRNA levels of 〖STBX〗IL-12, TNF-α, Arg-1, TGF-β, IL-10〖STBZ〗 and iNOS were analyzed by Real-time PCR, and protein levels of iNOS and Arg-1 were determined by Western blotting. The effect of T4-phage-induced re-polarization on the apoptosis and metastasis of Lewis lung cancer cells were evaluated by the flow cytometry and transwell assays, respectively. Results: RAW264.7 cells were successfully induced into an M2 phenotype with a significant increase in mRNA levels of 〖STBX〗Arg-1〖STBZ〗 and 〖STBX〗IL-10〖STBZ〗 (161.2 and 120.3 folds, respectively), together with a significant decrease in iNOS and 〖STBX〗IL-12〖STBZ〗 mRNA levels (3.3 and 7.8 folds, respectively). Both wild-type and the soc-hoc-T4 bacteriophages effectively induce M1 re-polarization of M2 type macrophages, but the induction activity of the soc-hoc-T4 phages was significantly stronger than that of the wild-type (P<0.05). Both wild-type and polarized M1 type macrophages more effectively induced apoptotic cell death ([35.3±2.44]%, [39.1±2.08]% vs [4.68±0.56]%, P<0.01) and suppressed the invasive capability in Lewis lung cancer cells ([43.8±7.51]%, [23.2±4.33]% vs [177.5±12.33]%, P<0.01), as compared with M2 macrophages. Conclusion: T4 bacteriophages can induce M1 re-polarization of M2 type macrophages, which results in an increase in apoptotic cell death and a decrease in invasive activity in Lewis lung cancer cells in vitro.

国家自然科学基金资助项目（No. 81001028）