[Neutrophil extracellular traps-induced endothelial cell damage in the pathogenesis of dermatomyositis-associated interstitial lung disease].

Objective: To explore the role of neutrophil extracellular traps (NETs)-induced endothelial cell damage in the pathogenesis of dermatomyositis (DM)-associated interstitial lung disease(ILD). Methods: Serum free DNA and krebs von den lungen-6 (KL-6) level were tested in healthy controls, dermatomyositis patients with or without interstitial lung disease (DM-ILD and DM-NILD). Subjects' peripheral blood neutrophils were stimulated with phorbol 12-myristate 13-acetate (PMA), then human umbilical vein endothelial cells (HUVECs) were co-cultured with NETs. The cell morphology was observed by the inverted phase contrast microscope. Cell viability was detected by cell counting kit-8 (CCK8). Results: The concentration of serum free DNA in DM patients [(271.27± 76.53) μg/L] was significantly higher than that in health control (HC)[(152.89±37.34) μg/L, P<0.001]. Moreover, free DNA level in DM-ILD patients [(302.67±74.15) μg/L] was higher than that in DM-NILD patients [(235.59±63.55 ) μg/L, P<0.005]. The concentration of KL-6in DM patients [(3.08±2.07) μg/L]was higher than that in HC[(0.87±0.51) μg/L, P<0.001]. Similarly, KL-6 in DM-ILD patients [(4.00±2.44) μg/L ] was higher than that of DM-NILD patients [(2.03±0.61) μg/L, P<0.005]. Free DNA and KL-6 were positively correlated (r=0.251, P<0.05). The survival of endothelial cells in DM group (53±11)% was lower than that of HC group [(70±5)%, P<0.001]. Not surprisingly, the survival of endothelial cells in DM-ILD group (44±4) % was lower than that in DM-NILD group [(61±8)%, P<0.01]. Conclusion: NETs could play an important role in the pathogenesis of dermatomyositis associated interstitial lung disease, suggesting that NETs may be the potential therapeutic target.目的： 探讨中性粒细胞胞外陷阱(NETs)诱导血管内皮细胞损伤在皮肌炎合并肺间质病变(ILD)中的作用。 方法： 检测健康对照者、皮肌炎患者(包括皮肌炎合并ILD者，皮肌炎未合并ILD者)的血清游离DNA浓度、血清涎液化糖链蛋白(KL－6)水平，分离受试者外周血中性粒细胞，体外用12－豆蔻酸－13－乙酸佛波醇(PMA)刺激获得NETs，用NETs刺激人脐静脉内皮细胞，倒置相差显微镜观察细胞形态，检测人脐静脉内皮细胞存活率来反映NETs对血管内皮细胞的损伤。 结果： 皮肌炎患者血清游离DNA浓度高于健康对照者[(271.27±76.53)μg/L比 (152.89±37.34)μg/L，P<0.001]，皮肌炎合并ILD者血清游离DNA浓度高于皮肌炎未合并ILD者[(302.67 ± 74.15)μg/L比(235.59 ±63.55)μg/L，P<0.005]；皮肌炎患者血清KL－6水平高于健康对照者[(3.08±2.07)μg/L比(0.87±0.51)μg/L，P<0.001]，皮肌炎合并ILD者血清KL－6水平高于皮肌炎未合并ILD者[(4.00±2.44)μg/L比(2.03±0.61)μg/L，P<0.005]。皮肌炎患者血管内皮细胞存活率低于健康对照者[(53±11)% 比(70±5)%，P<0.001]; 皮肌炎合并ILD者血管内皮细胞存活率低于皮肌炎未合并ILD者[(44±4)% 比(61±8)%，P<0.01]。相关分析，血清游离DNA浓度与血清KL－6水平呈正相关(r＝0.251，P<0.05)。 结论： NETs对皮肌炎合并ILD的发病有重要作用，可能是一个重要的治疗靶点。.