小鼠IgG免疫复合体通过活化NFκB诱导炎症细胞向气道募集和TNF介导的迟发性气道高反应性
2011/10/12
摘要
背景：哮喘患者气道表达的许多炎症蛋白均或多或少受到NF-κB的调节。阻断NF-κB活性能缓解哮喘的主要表现。因此研究哮喘中的NF-κB活化机制有可能给哮喘的治疗带来重大进展。但是除了知道其重要性之外，哮喘中NF-κB的活化机制尚不清楚。
目的：研究IgE和IgG抗体(Abs)在小鼠肺NF-κB 活化中的作用。
方法：对小鼠进行气管内（i.t.）IgE免疫复合物(IgE-IC) [抗2,4-二硝基苯半抗原(DNP) IgE + DNP-BSA或DNP-OVA]和致敏性抗IgE(LO-ME-2)滴注，以便观察IgE的作用。在研究IgG的作用时，小鼠经气管滴注了抗鸡γ球蛋白(CGG)复合物IgG1 mAb + CGG。采用凝胶迁移分析来检测NF-κB 的活化。利用较小的干扰性RNA阻断p50的表达。采用TNF单克隆抗体研究肿瘤坏死因子阻断后的效应。在前期建立的小鼠哮喘模型，评价气道高反应性（AHR）。
结果：单次气管内滴注IgE-IC或LO-ME-2不能诱导肺NF-κB 的活化。相反，单次滴注IgG-IC能诱导NF-κB及NF-κB依赖的促炎分子（如TNF和CXC趋化因子）的活化。采用p50小干扰RNA预处理后，滴注IgG-IC诱导的支气管肺泡灌洗液中TNF和巨噬细胞炎症蛋白-2水平显著下降。单次气管内滴注IgG-IC能诱导中性粒细胞和巨噬细胞向气道募集，诱导TNF介导的迟发性AHR，但不能诱导Th2细胞介导的哮喘表型。
结论：诱导肺内NF-κB活化与NF-κB依赖的促炎因子表达，然后诱导炎症细胞向气道募集以及TNF介导的迟发性AHR，主要是IgG的作用，而非IgE的作用。
背景：哮喘患者气道表达的许多炎症蛋白均或多或少受到NF-κB的调节。阻断NF-κB活性能缓解哮喘的主要表现。因此研究哮喘中的NF-κB活化机制有可能给哮喘的治疗带来重大进展。但是除了知道其重要性之外，哮喘中NF-κB的活化机制尚不清楚。
目的：研究IgE和IgG抗体(Abs)在小鼠肺NF-κB 活化中的作用。
方法：对小鼠进行气管内（i.t.）IgE免疫复合物(IgE-IC) [抗2,4-二硝基苯半抗原(DNP) IgE + DNP-BSA或DNP-OVA]和致敏性抗IgE(LO-ME-2)滴注，以便观察IgE的作用。在研究IgG的作用时，小鼠经气管滴注了抗鸡γ球蛋白(CGG)复合物IgG1 mAb + CGG。采用凝胶迁移分析来检测NF-κB 的活化。利用较小的干扰性RNA阻断p50的表达。采用TNF单克隆抗体研究肿瘤坏死因子阻断后的效应。在前期建立的小鼠哮喘模型，评价气道高反应性（AHR）。
结果：单次气管内滴注IgE-IC或LO-ME-2不能诱导肺NF-κB 的活化。相反，单次滴注IgG-IC能诱导NF-κB及NF-κB依赖的促炎分子（如TNF和CXC趋化因子）的活化。采用p50小干扰RNA预处理后，滴注IgG-IC诱导的支气管肺泡灌洗液中TNF和巨噬细胞炎症蛋白-2水平显著下降。单次气管内滴注IgG-IC能诱导中性粒细胞和巨噬细胞向气道募集，诱导TNF介导的迟发性AHR，但不能诱导Th2细胞介导的哮喘表型。
结论：诱导肺内NF-κB活化与NF-κB依赖的促炎因子表达，然后诱导炎症细胞向气道募集以及TNF介导的迟发性AHR，主要是IgG的作用，而非IgE的作用。
（苏楠 审校）
J Asthma. 2011 Aug 22. [Epub ahead of print]
J Asthma. 2011 Aug 22. [Epub ahead of print]
Source
Department of Immunology, Chonbuk National University Medical School , Jeonju , Republic of Korea .
Abstract
BACKGROUND：Many of the inflammatory proteins that are expressed in asthmatic airways are regulated, at least partially, by nuclear factor (NF)-κB. Blockade of NF-κB activity has resulted in attenuation of the cardinal features of asthma. Thus, delineating the mechanisms involved in NF-κB activation in asthma might provide an interesting approach to improving the management of asthma. However, despite its importance, the mechanism for NF-κB activation in asthma has not yet been determined.
OBJECTIVE：To examine the role of IgE and IgG antibodies (Abs) in the activation of NF-κB in mouse lungs.
METHODS：To examine the effect of IgE, mice underwent intratracheal (i.t.) instillation of an IgE immune complex (IgE-IC) (anti-2,4-dinitrophenyl hapten (DNP) IgE + DNP-BSA or DNP-OVA) and anaphylactogenic anti-IgE (LO-ME-2). For IgG, mice underwent i.t. instillation with a complex of anti-chicken gamma globulin (CGG) IgG1 mAb + CGG. NF-κB activation was determined by gel shift assay. Small interfering RNA was used for blockade of p50 expression. The effect of tumor necrosis factor (TNF) blockade was determined using anti-TNF Ab. A previously established murine model of asthma was used to assess airway hyperresponsiveness (AHR).
RESULTS：A single i.t. instillation of either IgE-IC or LO-ME-2 failed to induce activation of NF-κB in the lungs. In contrast, single i.t. instillation of IgG-IC was capable of inducing NF-κB activation, as well as NF-κB-dependent proinflammatory molecules, such as TNF and CXC chemokines. Pretreatment of p50 small interfering RNA decreased bronchoalveolar lavage fluid levels of TNF and macrophage inflammatory protein-2 induced by IgG-IC instillation. Single i.t. instillation of IgG-IC caused the recruitment of neutrophils and macrophages into the airway and TNF-mediated late AHR, but failed to induce Th2 cell-mediated asthmatic phenotypes.
CONCLUSION：IgG, but not IgE, is the major Ab that induces not only NF-κB activation and NF-κB-dependent proinflammatory molecules in the lungs but also subsequent recruitment of inflammatory cells into the airway and TNF-mediated late AHR.
J Asthma. 2011 Aug 22. [Epub ahead of print]
