PM2.5细颗粒物对大鼠肺组织损伤的分子免疫作用机理研究

发布时间：2018-02-28 20:31

  本文关键词： PM2.5 Smad RORγt FoxP3 SB431542　出处：《新疆医科大学》2015年硕士论文　论文类型：学位论文

【摘要】：目的:探讨PM2.5细颗粒物对大鼠肺组织损伤的分子免疫作用机制。方法:(1)观察大气细颗粒物PM2.5对大鼠肺部组织造成的病理学改变,并筛选出最适宜染毒剂量。(2)收集肺泡灌洗液进行白细胞分类及计数。取右肺组织病理学检查,荧光定量PCR法检测TGF-β1、Smad2/3、RORγt、Foxp3 mRNA水平的变化,同时对Smad2、RORγt、FoxP3 mRNA水平与血清中IL-6、IL-17a、TGF-β1表达的相关性进行分析。结果:(1)肺组织HE病理学改变:Ctrl、sham组肺泡腔大小均匀,肺泡壁完整,部分区域有少量出血及炎性细胞浸润;L、M、H组大鼠肺组织肺间隔增宽,同时见大量炎性细胞浸润,并随着剂量增加组织损伤加重,H组肺脓肿形成,炎性细胞崩解坏死。(2)ELISA检测显示Ctrl、sham、SB431542组之间血清IL-6、IL-17a、TGF-β1水平差异无统计学意义(P0.05);与Ctrl、sham、SB431542组相比,PM2.5组血清IL-6、IL-17a、TGF-β1水平增高(P0.05)。(3)Ctrl及sham组肺泡灌洗液中中性粒细胞、嗜酸性粒细胞、淋巴细胞和巨噬细胞计数差异无统计学意义(P0.05);与sham组相比,PM2.5组中性粒细胞、嗜酸性粒细胞、淋巴细胞均升高(P0.05),巨噬细胞计数降低(P0.05);与PM2.5组相比,SB431542组中性粒细胞、嗜酸性粒细胞、淋巴细胞降低(P0.05),巨噬细胞计数升高(P0.05)。(4)肺组织病理:Ctrl及sham组肺泡大小均匀,肺泡壁完整;PM2.5组肺组织内见大量炎性细胞浸润,肺间隔增宽;SB431542组肺组织损伤程度减轻,少量炎性细胞浸润。(5)Ctrl、sham组和SB431542组之间Smad2、TGF-β1、RORγt、Foxp3 mRNA水平差异无统计学意义(P0.05);与Ctrl、sham组和SB431542相比,PM2.5组Smad2、TGF-β1、RORγt、Foxp3 mRNA水平均增高(P0.05)。(6)相关性分析:肺组织Smad2 mRNA含量与血清中IL-6、IL-17a和TGF-β1成正相关,相关系数分别为(r=0.817,r=0.826,r=0.862,P0.05);RORγt mRNA水平与血清IL-6、IL-17a、TGF-β1表达呈正相关,相关系数分别为(r=0.890,r=0.823,r=0.818,P0.05);Foxp3 mRNA水平与血清IL-6、IL-17a、TGF-β1表达呈正相关,相关系数分别为(r=0.912,r=0.812,r=0.846,P0.05)。结论:大气细颗粒物PM2.5能够引起大鼠肺组织损伤,其损伤程度随染毒剂量的增加而加重。其可能的主要机制是TGF-β1表达增强,刺激肺部Smad2、RORγt和Fox P3表达,激发机体的免疫反应,使得血液中促炎性细胞因子IL-6、IL-17a、TGF-β1增多,从而导致组织的免疫炎性损伤。
[Abstract]:Objective: to investigate the molecular immunological mechanism of lung injury induced by fine particles of PM2.5 in rats. Methods: the pathological changes of lung tissue induced by PM2.5 were observed. The most suitable dose was selected to collect the alveolar lavage fluid for leukocyte classification and count. The right lung histopathology was used to detect the level of TGF- 尾 1 Smad2 / 3 ROR 纬 tFoxp3 mRNA. At the same time, the correlation between the level of FoxP3 mRNA and the expression of IL-6 / IL-17a- 尾 _ 1 in serum was analyzed. Results: the pathological changes of lung tissue were as follows: the size of alveolar cavity was uniform and the alveolar wall was intact. A small amount of hemorrhage and inflammatory cell infiltration were observed in some areas. The pulmonary septum was enlarged and a large number of inflammatory cells were infiltrated in the lung tissue of the rats in the LG-MU H group, and the pulmonary abscess was formed with the increase of the dose of the tissue injury in the H group. The results of Elisa showed that there was no significant difference in serum levels of IL-6, IL-17a1 and TGF- 尾 1 between the two groups, but the levels of IL-6 and IL-17a TGF- 尾 1 in PM2.5 group were significantly higher than those in Ctrlsb 43 1542 group, and the levels of neutrophils, eosinophils, eosinophils in alveolar lavage fluid of sham group were higher than those in PM2.5 group. Compared with sham group, neutrophil, eosinophil and lymphocyte in PM2.5 group increased P0.05, macrophage count decreased P0.05G, compared with PM2.5 group, neutrophil, eosinophil in SB431542 group, eosinophilic granulocyte, neutrophil, eosinophilic granulocyte, neutrophil, eosinophilic granulocyte, and eosinophilic granulocyte in PM2.5 group. The alveolar size of lung tissue was uniform in the group of lung pathology: the alveolar size was uniform, the alveolar wall was intact and PM2.5 group had a large number of inflammatory cells infiltration, and the injury degree of lung tissue was reduced in group SB431542. There was no significant difference in the levels of Smad2TGF- 尾 1 TGF- 尾 1tFoxp3 mRNA between the Smad2TGF- 尾 1 TGF- 尾 1 and SB431542 groups, but there was a positive correlation between the levels of Smad2TGF- 尾 1 TGF- 尾 1 Foxp3 mRNA and the serum levels of IL-6mil IL-17a and TGF- 尾 1 in the lung tissue compared with those in the Ctrlsham group and SB431542 group. There was a positive correlation between the level of ROR 纬 t mRNA and the expression of TGF- 尾 1 in serum IL-6, IL-17a- 尾 1, respectively. The correlation coefficient was that the level of Foxp3 mRNA was positively correlated with the expression of IL-6IL-17a- 尾 1 in serum. Conclusion: the level of PM2.5 can cause lung tissue injury in rats. The possible mechanism is that the expression of TGF- 尾 1 is increased, the expression of Smad2T ROR 纬 t and Fox P3 is stimulated, the immune response of the body is stimulated, and the pro-inflammatory cytokine IL-6, IL-17a- 尾 1 in the blood is increased. This leads to the immune inflammatory injury of the tissue.
【学位授予单位】：新疆医科大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R563;X513
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本文编号：1548834