Objective: To investigate the modulation role of Gas6 in silica-induced inflammatory effect on human macrophages. Methods: Differentiated THP-1 macrophages were exposed to different concentrations of silica for 6 h and 24 h. Additionally, silica-activated macrophages were treated with different concentrations of recombine human Gas6 and Gas6 antibody respectively. Cell viabilities were determined by CCK-8 kit. Expression levels of Gas6 and inflammatory cytokines (TNF-α, IL-1β and IL-6) were measured by ELISA assay kits. Results: Silica particles induced clear dose-dependent decreases of cell viability and Gas6 expression at both 6 h and 24 h. The cell viability of 24 h is lower than 6 h at the same concentration of silica (P<0.05). Furthermore, silica activated macrophages treated with Gas6 antibody induced significant decreases of Gas6 both at 6 h and 24 h (P<0.05). After pretreated with various concentrations of Gas6 antibody, silica induced higher expressions of inflammatory cytokines (TNF-α, IL-1β, IL-6) in dose-dependent manners at two time points. Addition of exoge-nous Gas6 significantly suppressed silica-induced inflammatory cytokines concentrations mentioned above in the cell culture supernatants in clear dose-dependent manners. Conclusion: Exogenous Gas6 could inhibit the secre-tion of inflammatory cytokines in macrophages, while the block of Gas6 might enhance this inflammation.
目的：通过体外实验探讨Gas6对石英粉尘引起的巨噬细胞分泌炎性因子水平的调节作用。 方法：实验采用50、100、200、400 μg/ml标准石英粉尘刺激THP-1诱导的人巨噬细胞6 h和24 h，同时设定不同程度的Gas6阻断组和Gas6补充组。通过CCK-8法测定细胞活力，通过酶联免疫吸附试验检测细胞培养上清液中Gas6和相关炎性因子肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1β和IL-6的表达量。 结果：随染石英粉尘浓度增加和时间延长，巨噬细胞细胞活力降低，相同染尘浓度下，染尘24 h组细胞活力均低于染尘6 h组。与对照组比较，随石英粉尘浓度升高，Gas6蛋白表达量下降，呈剂量-效应关系。加入Gas6抗体作用6 h和24 h的细胞活力均低于相应时间点的单纯染尘组，差异有统计学意义（P<0.05）。加入不同浓度Gas6抗体后，可明显增强石英粉尘诱导巨噬细胞炎性反应水平，TNF-α、IL-1β、IL-6表达明显增加，呈剂量-效应关系。补充Gas6后，Gas6表达量明显高于基础表达量，差异有统计学意义（P<0.05）。补充Gas6后，可明显降低石英所致巨噬细胞释放的TNF-α、IL-1β、IL-6水平，且随着Gas6浓度增加，上述炎性因子水平逐渐降低，呈现明显的剂量-效应关系。 结论：外源性Gas6可抑制石英粉尘所致巨噬细胞的炎性反应，特异性阻断Gas6则会明显增强该炎性反应。.
Keywords: Gas6; Macrophage; Quartz.