白细胞介素27滴鼻预防给药通过STAT1信号通路减轻卵白蛋白诱导的哮喘小鼠气道过敏性炎症

Intranasal Administration of Interleukin-27 Alleviates Airway Allergic Inflammation of Ovalbumininduced Mouse Asthma Model via STAT1 Signal Pathway

目的从动物水平探索白细胞介素27(IL-27)是否能减轻哮喘的过敏性气道炎症,并在细胞水平进行相关机制研究。方法将60只雌性C57/6J小鼠随机分成对照组、哮喘组、IL-27滴鼻预防组和IL-27滴鼻治疗组。在卵白蛋白(OVA)腹腔注射致敏与滴鼻激发诱导的小鼠哮喘模型基础上,加用IL-27干预,一种为"IL-27小剂量、多次预防模型",另一种为"IL-27大剂量、寡次治疗模型"。取肺组织进行HE染色和炎症病理评分。小鼠脾脏纯化的CD4+T淋巴细胞进行体外分化实验,并加用IL-27处理,用ELISA检测IL-4的水平。CD4+T淋巴细胞在不同强度的Th2环境下诱导分化,用IL-27刺激细胞,提取总蛋白,行蛋白免疫印迹法检测信号转导与转录激活子1(STAT1)和STAT1磷酸化水平。结果 IL-27小剂量、多次预防给药,可以明显抑制支气管及血管周围的炎症细胞浸润,炎症病理评分明显低于哮喘组(P<0.05),而与治疗组比较则差异无明显的统计学意义(P>0.05)。IL-27能明显抑制初始CD4+T淋巴细胞向Th2方向分化,且这种作用不依赖于γ干扰素和IL-10。IL-27的抑制作用是通过STAT1信号通路。在哮喘小鼠或高剂量IL-4培养分化环境中,CD4+T淋巴细胞的STAT1磷酸化受损。结论 IL-27可抑制初始CD4+T淋巴细胞向Th2分化的作用,但对已朝Th2分化的细胞,其抑制作用明显减弱。IL-27的预防性效果比治疗效果显著。哮喘气道局部业已存在已分化的Th2淋巴细胞是IL-27作用降低的原因之一。

Objective To observe whether interleukin-27（ IL-27） intervention could diminish allergic airway inflammation of mouse asthma induced by ovalbumin（ OVA） and to investigate the related molecular mechanisms.Methods Sixty female C57 /6J mice were randomly divided into six groups,a control group,an asthma group,two IL-27 prevention groups and two IL-27 treatment groups.Based on being sensitized and challenged with OVA in the asthma model,two kinds of IL-27 intervention asthma models were set up,one of which was low-dose multiple prevention model,the other was high-dose few times treatment model.HE stain and inflammation score were done for the lungs.CD4＋T cells were purified from mice spleen and cultured under Th2 medium with / without IL-27.Interleukin-4（ IL-4） was measured by ELISA.CD4＋T cells were cultured under different stringent Th2 medium and stimulated by IL-27.The level of total signal transducer and activator of transcription-1（ STAT1） protein and phos-STAT1 were tested by Western blot.Results In low-dose multiple prevention group,IL-27 inhibited inflammation around bronchial and vascular obviously,the inflammation score was lower than the asthma group（ P〈0.05）,while the treatment group had no obvious statistical significance（ P〈0.05）.IL-27 repressed Th2 differentiation of nave CD4＋T cells which was independent of interferon-γ and IL-10.This effect was via STAT1 signaling pathway.CD4＋T cells from asthma mice or cultured under high-IL-4 inducing medium were found impairment of STAT1 phosphorylation.Conclusions IL-27 could inhibit Th2 differentiation of nave CD4＋T cells,but not in already committed Th2-CD4＋T cells.The inhibition effect of IL-27 for airway inflammation is obvious in prevention group,while the treatment group shows obviously resistance to inhibitory effect of IL-27.Already committed Th2-CD4＋T cells existed in asthma airway might be the reason for IL-27 resistance.