吸入毒理云暴露系统的阳性验证体系的摸索

Mapping positive validation system of inhalation toxicology cloud exposure system

目的探索云暴露系统用于吸入毒理体外暴露实验的可行性。方法采用高、中、低(800、400、200 mg·L^(-1))3个浓度的脂多糖(lipopolysaccharide,LPS)通过云暴露系统对气液界面(air-liquid interface,ALI)培养的Calu-3细胞进行暴露,磷酸盐缓冲液(phosphate buffer solution,PBS)暴露作阴性对照组,暴露1次,另取高浓度LPS溶液暴露5次,暴露结束后3 h和24 h分别检测Calu-3细胞的活性、乳酸脱氢酶(LDH)释放量、跨上皮电阻值(TEER)、黏蛋白MUC5AC以及炎症因子IL-6、IL-8、TNF-α表达。结果与PBS阴性对照组相比,高、中、低3种浓度的LPS气液界面暴露于Calu-3细胞模型后,细胞的活性、LDH释放量无显著变化,但细胞电阻值降低,细胞的屏障功能受损;随着暴露浓度的升高,LPS促进细胞黏蛋白MUC5AC的表达,使细胞IL-6、IL-8表达下降,TNF-α表达上升;随着暴露频率的增加,LPS会抑制黏蛋白的表达,使IL-6表达上升;暴露频率增加的同时延长暴露后的检测时间会使细胞IL-8、TNF-α表达上升。结论ALI云暴露的方式可以有效反映细胞对阳性受试物的反应,此体外暴露方法可以用于后续暴露实验来评价化合物的吸入毒性。

Aim To explore the feasibility of the cloud exposure system for in vitro exposure experiments on inhalation toxicology.Methods Calu-3 cells cultured at the air-liquid interface(ALI)were exposed to three concentrations of lipopolysaccharide(LPS):high,medium,and low(800,400,200 mg·L^(-1))by the cloud exposure system,and phosphate buffer solution(PBS)was used as a negative control group for one exposure,while the high concentration of LPS was used to expose Calu-3 cells for five times.Calu-3 cells were exposed to phosphate buffer solution(PBS)once as negative control group and to high concentration of LPS solution for five times,and the activity of Calu-3 cells,the release of lactate dehydrogenase(LDH),TEER,mucin MUC5AC,and the expression of inflammatory factors IL-6,IL-8 and TNF-αwere detected 3 h and 24 h after the end of the exposure,respectively.Results Compared with the PBS-negative control group,after exposure to the Calu-3 cell model at the air-liquid interface with three concentrations of LPS,high,medium,and low,there were no significant changes in the activity and LDH release,but the cellular electrical resistance value was reduced,and the barrier function of the cells was impaired;with the increase of the exposure concentration,the LPS promoted the expression of the cellular mucin MUC5AC,which led to a decrease in the expression of cellular IL-6,IL-8,and a decrease in the expression of TNF-α.Expression of IL-6 and IL-8 decreased and TNF-αexpression increased;as the frequency of exposure increased,LPS inhibited the expression of mucin and increased the expression of IL-6;an increase in the frequency of exposure along with a prolongation of post-exposure assay time resulted in an increase in the expression of cellular IL-8 and TNF-α.Conclusions The ALI cloud exposure approach can effectively reflect the cellular response to positive subjects,and this in vitro exposure can be used in subsequent exposure experiments to evaluate the inhalation toxicity of compounds.