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、400μg/ml标准石英粉尘刺激THP-1诱导的人巨噬细胞6h和24h,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24h组细胞活力均低于染尘6h组。与对照组比较,随石英粉尘浓度升高,Gas6蛋白表达量下降,呈剂量一效应关系。加入Gas6抗体作用6h和24h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,呈剂量一效应关系。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,呈现明显的剂量一效应关系。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。
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 exogenous Gas6 significantly suppressed silica-induced inflammatory eytokines concentrations mentioned above in the cell culture supernatants in clear dose-dependent manners. Conclusion Exogenous Gas6 could inhibit the secretion of inflammatory cytokines in macrophages, while the block of Gas6 might enhance this inflammation.