SiO2对血小板源性生长因子蛋白表达及胶原合成的影响

目的 探讨siO2刺激矽肺患者的肺泡巨噬细胞(AM)及其介导的人胚肺成纤维细胞(HELF)血小板源性生长因子(PDGF)的蛋白表达及胶原合成.方法 收集矽肺患者AM,体外经SiO2刺激3、6、12、18、24、36 h,收集培养上清,用ELISA法检测AM上清中PDGF的蛋白表达,用其表达峰值时的培养上清与HELF共同孵育6、12、18、24、36、48 h,用免疫细胞化学法及Western blot法分别检测HELF及其培养上清中PDGF的蛋白表达情况,用3H-脯氨酸掺入法检测HELF胶原的合成与分泌情况.结果 经SiO2刺激的矽肺患者AM条件上清中PDGF的蛋白表达量在作用24 h时最高(平均吸光度值为0.282±0.019),与同期对照组(平均吸光度值为0.214±0.014)相比,差异有统计学意义(P<0.01). 用AM上清作用于HELF后,HELF细胞内及其培养上清中PDGF的蛋白表达均升高,与对照组比较,HELF培养上清中PDGF蛋白表达于12、18、24、36、48 h时明显增高,HELF中PDGF蛋白表达于18、24、36、48 h时明显增高,差异均有统计学意义(P<0.05).矽肺患者AM培养上清与HELF共同孵育不同时间后,HELF细胞内及培养上清中胶原明显增加.结论 SiO2通过AM的介导影响了HELF中PDGF的蛋白表达与胶原合成及分泌.

Effect of SiO2 on expression of platelet derived growth factor in human silicotic alveolar macrophages and human embryonic lung fibroblasts

Objective To study the effect of SiO2 on the expression of platelet derived growth factor (PDGF)in human silicotic alveolar macrophages (AM) and human embryonic lung fibroblasts (HELF).Methods Human alveolar macrophages were collected from a silicotic patient by bronchoalveolar lavage and exposed to SiO2 for 3,6, 12,18,24 and 36 h. The cultured supernatant at 24 h was incubated with human em-bryonic lung fibrob-lasts for 6, 12,18,24,36 and 48 h. The immunocytochemistry and Western blot were used to detect the level of expression of PDGF in lung fibroblasts and their supernatant respectively. 3H-proline was used to detect the synthesis and secretion of collagen in HELF. Results The expression of the PDGF in the supernatant of alveolar macrophages exposed to SiO2 increased significantly and reached the peak at 24 h (av-erage optical density:0.282±0.019 vs 0.214±0.014,P<0.01) with ELISA. The expression of PDGF in lung fi-broblasts and their su-pernatant increased at different time (6, 12,18,24,36 and 48 h) with immunocyto-chemistry and Western blot respectively when incubated with the cultured supernatant of silicotic AM exposed to SiO2. The expression of PDGF was significantly different from the control group(P<0.05). The synthesis and secretion of collagen in FB were increased markedly when incubated with the cultured supernatant of AM stimulated by SiO2 compared with the control group. Conclusion SiO2 may affect the expression of PDGF and synthesis of collagen through AM mediation and participate in the formation of lung fibrosis.