沙尘暴PM_(2.5)、PM_(10)对大鼠肺泡巨噬细胞吞噬功能的影响

目的　探讨了沙尘暴PM2 5、PM10 对大鼠肺泡巨噬细胞吞噬功能的影响。方法　沙尘暴颗粒物采集自北京市城区 ,细胞毒性测定用MTT法 ,巨噬细胞吞噬功能采用流式细胞法 ,以荧光标记的胶珠 (Latexbeads ,D =2 4 μm)来测定。 结果　MTT结果显示 ,随着染毒浓度的增加 ,巨噬细胞存活率逐渐减低 ,高剂量组约为对照的 85 %左右。流式细胞仪分析表明 ,各颗粒物染毒组细胞的平均荧光强度逐渐减弱 ,提示巨噬细胞摄入沙尘暴颗粒物后 ,其吞噬荧光胶珠的能力明显减低 ;另外各染毒组的平均侧向光散射强度 ,即摄入的总颗粒数 (沙尘暴颗粒 +荧光胶珠 )低于对照 ,提示巨噬细胞的吞噬功能受到了损伤。沙尘暴PM2 5的细胞毒性比相同浓度的PM10 大 ,对吞噬功能的损伤也更明显。结论　沙尘暴PM2 5、PM10 均能损伤大鼠肺泡巨噬细胞的吞噬功能 ,削弱其非特异性防御能力。

Impact of dust storm PM2.5 and PM10 on the phagocytic function of alveolar macrophages of rat

OBJECTIVE: To investigated effects of dust storm PM2.5 and PM10 on the phagocytosis of rat alveolar macrophages. METHODS: PM2.5 and PM10 were collected during dust storm period in the urban area of Beijing. Cytotoxicity of PM2.5 and PM10 was measured by MTT method. Flow cytometry analysis was applied to characterize effects of PM2.5 and PM10 on the phagocytosis of alveolar macrophages. RESULTS: PM2.5 and PM10 were toxic to rat alveolar macrophages at the concentrations above 20 micrograms/ml. PM2.5 and PM10 impaired phagocytic function of alveolar macrophages in a dose-dependent manner. PM2.5 was more potent than PM10. CONCLUSION: Dust storm PM2.5 and PM10 could impair the phagocytosis of rat alveolar macrophages, that may in turn impair the airway nonspecific defenses function.