Kupffer细胞在肝癌发生发展中的双向作用

Effects of the culture supernatants of Mφ1 and Mφ2 on the killing activity of human γδT cells against gastric cancer SGC-7901 cells in vitro

AIM: To investigate the effects of the culture supernatants of classically activated macrophages (Mφ1) and alternatively activated macrophages (Mφ2) on the proliferation, cytotoxicity, and surface maker expression of gamma delta T (γδT) cells and explore potential mechanisms involved.

METHODS: Mφ1 were induced in vitro with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon-γ (IFN-γ), while Mφ2 were induced with macrophage colony-stimulating factor (M-CSF). The isopentenyl pyrophosphate method was used to amplify human peripheral blood γδT cells. The surface markers on macrophages and γδT cells were determined by flow cytometry (FCM). Interleukin-10 (IL-10) and IL-12 levels in the culture supernatants of Mφ1 and Mφ2 were determined by enzyme-linked immunosorbant assay (ELISA) using commercial kits. The proliferation of γδT cells induced with the culture supernatants of Mφ1 and Mφ2 was investigated by methyl thiazoly tetrazolium (MTT) assay. The lactate dehydrogenase (LDH) method was used to detect the cytotoxicity of γδT cells against gastric cancer SGC-7901 cells.

RESULTS: After 10 days of induction culture, approximately 73.2% and 61.8% of Mφ1 and Mφ2 highly expressed CD68, respectively. The level of IL-12 secreted by Mφ1 was significantly higher than that secreted by Mφ2 (35 mg/L vs 9 mg/L, P < 0.001). The level of IL-10 secreted by Mφ1 was significantly lower than that secreted by Mφ2 (15 mg/L vs 87 mg/L, P < 0.001). The culture supernatant of Mφ1 could increase the proliferation of γδT cell when compared with those of Mφ2 and control cells (338% vs 11% and 0%, respectively; both P < 0.01). The positive rate of surface maker γδT cell receptor (γδTCR) on γδT cells induced with the culture supernatant of Mφ1 was higher than those on γδT cells induced with the culture supernatants of Mφ2 and control cells (97.3% vs 89.1% and 91.3%, respectively; both P < 0.05). The culture supernatant of Mφ1 could increase the cytotoxicity of γδT cells when compared with those of Mφ2 and control cells (70.18% vs 51.38% and 47.25%, respectively; both P < 0.01).

CONCLUSION: The culture supernatant of Mφ1 can increase the proliferation and cytotoxicity of γδT cells, whereas the culture supernatant of Mφ2 has no significant effects.