结核杆菌诱导的凋亡中性粒细胞对人巨噬细胞活性的影响

Influence of the Mycobacterium tuberculosis-infected apoptotic neutrophils on the activities of human macrophages

目的探讨结核杆菌诱导的凋亡中性粒细胞对人巨噬细胞活性的影响。方法从人外周血中分离中性粒细胞和单核细胞,用结核杆菌感染中性粒细胞诱导其凋亡,再用单核细胞来源的巨噬细胞吞噬凋亡粒细胞,培养18h后测定其细胞因子产生情况。结果吞噬结核杆菌诱导的凋亡粒细胞可促进人巨噬细胞产生致炎症细胞因子TNF-α,但不影响抗炎症细胞因子TGF-β和IL-10的产量。结论结核杆菌诱导的凋亡中性粒细胞,能增强人单核细胞来源的巨噬细胞的活性,代表一种新的宿主防御机制。

Many bacteria can induce apoptosis in human neutrophils, but little is known how these infected apoptotic neutrophils can influence the activation of macrophages. In the present study, the influence of the Mycobacteria tuberculosis-infected apoptotic neutrophils on the activities of human macrophages was investigated by using apoptotic neutrophils induced by UV-irradiation as well as by infection with M. tuberculosis. It was demonstrated that the M. tuberculosis-infected apoptotic neutrophils, just as the UV-induced apoptotic neutrophils, could enhance the production of the pro-inflammatory cytokine TNF-α, but not the anti-inflammatory cytokine TGF-β and IL-10, indicating that the apoptosis of neutrophils may represent a new protective mechanism to regulate the host responses to bacterial infection by enhancing the macrophage activation.