NETs刺激下慢性支气管炎大鼠血清ANCA产生机制探讨

Neutrophil extracellular traps induce production of MPO-ANCA in chronic bronchitis rats

目的:探讨长期慢性感染刺激诱导机体产生抗中性粒细胞胞浆抗体(ANCA)的机制。方法:烟熏法联合脂多糖气管内注入,建立慢性支气管炎大鼠模型,用佛波脂(PMA)体外刺激大鼠中性粒细胞产生中性粒细胞胞外网络(NETs),以NETs免疫慢性支气管炎大鼠,比较慢性支气管炎NETs刺激组(CB/NETs)、慢性支气管炎组(CB)和正常组三组大鼠血清髓过氧化物酶-抗中性粒细胞胞浆抗体(MPO-ANCA)、血清瓜氨酸化的组蛋白H3(Cit H3)、血清IFN-α水平及血清肌酐、血清尿素氮、尿红细胞计数、24 h尿蛋白定量水平。结果:(1)CB/NETs组的血清MPO-ANCA水平明显高于CB组及正常组,(62.4975±19.637 64)ng/ml vs(17.380 6±4.886 49)ng/ml,(20.888 4±4.396 07)ng/ml(P<0.01)。(2)CB/NETs组的血清Cit H3水平明显高于CB组及正常组,(32.597 4±20.291 5)ng/ml vs(8.856 8±2.366 92)ng/ml,(5.622 5±0.837 38)ng/ml,(P<0.05,P<0.01)。(3)CB/NETs组中有两只大鼠的血清IFN-α水平异常升高(3 735.7、3 428.4 pg/ml)。(4)三组大鼠的肾脏相关指标差异暂未呈现出统计学意义。(5)大鼠血清Cit H3水平与血清MPO-ANCA水平呈正相关(r=0.61,P<0.05)。结论:慢性支气管炎长期、反复感染可导致ANCA水平升高,从形成高水平的ANCA到最终形成ANCA相关性小血管炎尚需要时间。

Objective： To investigate the mechanism of chronic bronchitis with recurrent long duration infections in the production of MPO anti-neutrophil cytoplasmic antibodies（ ANCA）. Methods： Rats were gave intratracheal injection of LPS and smoked to established chronic bronchitis（ CB） model. Rat neutrophils were incubated with phorbol-12-myristate-13-acetate（ PMA） to induce Neutrophil extracellular traps（ NETs）. NETs were then used to immune chronic bronchitis rats. Serum concentrations of myeloperoxidase anti-neutrophil cytoplasmic antibodies（ MPO-ANCA）,Citrullinated Histone H3（ Cit H3）,Interferon-α（ IFN-α） were evaluated. Results：（ 1） The serum levels of MPO-ANCA in chronic bronchitis rats immuned with NETs（ CB/NETs） were significantly higher than those in chronic bronchitis rats（ CB） and healthy control rats,（ 62. 497 5 ± 19. 637 64） ng/ml vs（ 17. 380 6 ± 4. 886 49） ng/ml,（ 20. 888 4 ±4. 396 07） ng/ml（ both P〈0. 01）.（ 2） The serum levels of Cit H3 in CB/NETs rat were significantly higher than those in CB rat and healthy control rats,（ 32. 597 4±20. 291 5） ng/ml vs（ 8. 856 8±2. 366 92） ng/ml,（ 5. 622 5 ±0. 837 38） ng/ml（ P〈0. 05,P〈0. 01）.（ 3） The serum levels of IFN-α were found increased sharply in two CB/NETs rats（ 3 735. 7,3 428. 4 pg/ml）.（ 4） Renal function among three groups showed no significant difference yet.（ 5） Serum Cit H3 level showed a positive correlation with serum MPO-ANCA level（ r = 0. 61,P〈0. 05）. Conclusion： Chronic bronchitis with recurrent infections could induce the production of ANCA probably by the stimulation of NETs,but whether it might develop to AAV remains need a duration.