摘要
目的矽肺是一种以肺纤维化为病理特征的疾病,其发病机制仍不完全清楚,外周血单核细胞表型偏移失衡在肺纤维化病理进展中发挥着重要作用。文中旨在研究石英诱导小鼠矽肺（pneumosilicosis）模型中循环单核细胞亚群在不同病理阶段的变化特点,探讨其动态变化与肺炎症损伤和纤维化的关系。方法 100只雄性C57BL/6小鼠（18～22 g）随机数字表法分为等渗盐水组和石英组,石英组滴注吸入40 m L石英混悬液（100 mg/kg）,等渗盐水组滴注吸入相同体积无菌等渗盐水。经术后第1、3、7、14和28天应用流式细胞术检测循环单核细胞亚群变化;常规支气管肺泡灌洗术后进行炎症细胞分类计数;HE染色和苦味酸天狼星红染色检测小鼠肺组织炎症评分及胶原容积分数。结果病理染色显示,造模后第7天,小鼠肺组织可见明显的矽结节;与等渗盐水组相比,石英组小鼠肺组织炎症评分、胶原容积分数显著升高[（1.400±0.089）vs（0.920±0.049）、（1.950±0.065）vs（0.525±0.048）,P〈0.01],并持续到第28天[（1.520±0.136）vs（0.800±0.089）,（5.300±0.776）vs（0.850±0.050）,P〈0.01];与相应时间点等渗盐水组比较,石英组BAFL细胞总数于第1天开始升高[（7.693±2.495）vs（2.008±0.901）,P〈0.01],在第3天达到高峰[（13.346±3.563）vs（1.044±0.695）],随后第7、14、28天呈现递减趋势,但仍都高于等渗盐水组（P〈0.01）;石英组BALF巨噬细胞绝对值在第3天时显著高于等渗盐水组（6.821±2.627 vs 0.980±0.663,P〈0.01）,并在第7天维持于高水平状态[（6.697±1.864）vs（1.225±0.601）,P〈0.01],后呈下降趋势,但第14及28天巨噬细胞绝对值仍高于等渗盐水组（P〈0.01）;石英组BALF中性粒细胞绝对值在第1、3、7及14天都显著高于等渗盐水组（P〈0.01）,且呈现出逐渐下降的趋势,在第28天与等渗盐水组差异无统计学意义（P〉0.05）。石英组小鼠Ly6Chi单核细胞亚群占比在所有检测时间点均显著高于等渗盐水组（P〈0.01）,其中第7天达到高峰[（78.300±2.517）vs（58.750±2.386）,P〈0.01];Ly6Clo亚群比例变化与之相反。第7天和第28天的小鼠Ly6Chi单核细胞亚群占比与相应时间点的IS及CVF值呈正相关（P〈0.01）。结论循环Ly6Chi和Ly6Clo单核细胞亚群占比在石英诱导的小鼠矽肺的不同病理时期呈现动态变化,持续性的Ly6Chi单核细胞亚群占比升高可能与矽肺的急慢性炎症及后期的纤维化程度存在密切的联系。
Objective Pneumosilicosis is characterized by pulmonary fibrosis and cannot be effectively treated at present.This study was to explore the changes of monocyte subsets in the mouse model of silicon dioxide-induced experimental pneumosilicosis and the correlation of the changes with lung inflammatory injury and pulmonary fibrosis. Methods A total of 100 male C57 BL /6J mice weighing 18- 22 g were equally randomized into a normal saline（ NS） group and a silicon dioxide（ quartz） group. The model of experimental pneumosilicosis was established by oropharyngeal aspiration of quartz suspension. At 1,3,7,14,and 28 days after treatment,the mice were sacrificed and the proportions of different circulating monocyte subpopulations determined by flow cytometry. Different types of inflammatory cells in the bronchoalveolar lavage fluid（ BALF） were routinely counted. The inflammation score and collagen volume fraction（ CVF） of the lung tissue were obtained by HE and picrosirius red staining. Results At 7 days after quartz treatment,silicotic nodules were observed in the lung tissue. Compared with the NS controls,the model mice showed significantly increased inflammation score and CVF at 7 days（ 0. 920 ± 0. 049 vs 1. 400 ± 0. 089,P﹤0. 01; 0. 525 ± 0. 048 vs 1. 950 ± 0. 065,P﹤0. 01） and 28 days（ 0. 800 ± 0. 089 vs 1. 520 ± 0. 136,P﹤0. 01; 0. 850 ± 0. 050 vs 5. 300 ± 0. 776,P﹤0. 01）. In comparison with the NS group,the quartz group also exhibited significant increases in the number of total cells at days 1- 28（ P﹤0. 01） and the count of neutrophils at days 1- 14（ P﹤0. 01） in the bronchoalveolar lavage fluid（ BALF） of the model mice,as well as in the number of macrophages in the BALF at 3 days（ 0. 980 ± 0. 663 vs 6. 821 ± 2. 627,P﹤0. 01）,7 days（ 1. 225 ± 0. 601 vs 6. 697 ± 1. 864,P﹤0. 01）,14 days（ 1. 492 ± 0. 438 vs 2. 574 ± 0. 396,P﹤0. 01）,and 28 days（ 2. 035 ± 0. 456 vs 3. 249 ± 0. 492,P﹤0. 01）. The count of neutrophilic granulocytes in the BALF was remarkably higher in the quartz than in the NS group at 1,3,7,and 14 days（ P﹤0. 01） but not at 28 days（ P﹤0. 05）. Compared with the NS controls,the quartz-treated mice showed markedly increased proportion of Ly6 Chimonocytes at all time points,which peaked at 7 days（ 58. 750 ± 2. 386 vs 78. 300 ± 2. 517,P﹤0. 01）,with a positive correlation with the inflammation score（ P﹤0. 01） and CVF of the lung tissue（ P﹤0. 01） at 7 and 28 day. Conclusion The proportions of circulating Ly6 Chiand Ly6Clomonocytes changed dynamically in the murine model of quartz-induced experimental pneumosilicosis. The increased proportion of the Ly6 Chimonocyte subpopulation might be closely related with lung inflammatory injury and pulmonary fibrosis in pneumosilicosis.
出处
《医学研究生学报》
CAS
北大核心
2016年第5期453-459,共7页
Journal of Medical Postgraduates
基金
国家自然科学基金(81102088
81441101)
天津市应用基础研究及前沿技术研究计划项目(12JCYBJC16600
13JCYBJC22000)
武警后勤学院附属医院种子基金(FYZ201510)
武警医学院科研基金(WYB201007)
