Unit of Respiratory Immunopharmacology, Department of Experimental Medical Science, Lund University, Lund, Sweden.
PLoS One. 2013 Apr 29;8(4):e62718. doi: 10.1371/journal.pone.0062718. Print 2013.
Rhinovirus (RV) infections cause exacerbations and development of severe asthma highlighting the importance of antiviral interferon (IFN) defence by airway cells. Little is known about bronchial smooth muscle cell (BSMC) production of IFNs and whether BSMCs have dsRNA-sensing receptors besides TLR3. dsRNA is a rhinoviral replication intermediate and necrotic cell effect mimic that mediates innate immune responses in bronchial epithelial cells. We have explored dsRNA-evoked IFN-β and IFN-λ1 production in human BSMCs and potential involvement of TLR3 and RIG-I-like receptors (RLRs). Primary BSMCs were stimulated with 0.1-10 µg/ml dsRNA, 0.1-1 µg/ml dsRNA in complex with the transfection agent LyoVec (dsRNA/LyoVec; selectively activating cytosolic RLRs) or infected with 0.05-0.5 MOI RV1B. Both dsRNA stimuli evoked early (3 h), concentration-dependent IFN-β and IFN-λ1 mRNA expression, which with dsRNA/LyoVec was much greater, and with dsRNA was much less, after 24 h. The effects were inhibited by dexamethasone. Further, dsRNA and dsRNA/LyoVec concentration-dependently upregulated RIG-I and MDA5 mRNA and protein. dsRNA and particularly dsRNA/LyoVec caused IFN-β and IFN-λ1 protein production (24 h). dsRNA- but not dsRNA/LyoVec-induced IFN expression was partly inhibited by chloroquine that suppresses endosomal TLR3 activation. RV1B dose-dependently increased BSMC expression of RIG-I, MDA5, IFN-β, and IFN-λ1 mRNA. We suggest that BSMCs express functional RLRs and that both RLRs and TLR3 are involved in viral stimulus-induced BSMC expression of IFN-β and IFN-λ1.
鼻病毒（RV）感染会导致哮喘恶化和加重，突出了气道细胞抗病毒干扰素（IFN）防御的重要性。关于支气管平滑肌细胞（BSMC）产生 IFN 的情况知之甚少，以及 BSMC 是否除 TLR3 之外还具有 dsRNA 感应受体。dsRNA 是鼻病毒复制的中间产物和坏死细胞效应模拟物，可介导支气管上皮细胞的固有免疫反应。我们已经探讨了人 BSMC 中 dsRNA 引发的 IFN-β 和 IFN-λ1 的产生，以及 TLR3 和 RIG-I 样受体（RLRs）的潜在参与。用 0.1-10 µg/ml dsRNA、0.1-1 µg/ml dsRNA 与转染剂 LyoVec 形成复合物（dsRNA/LyoVec；选择性激活细胞质 RLR）或 0.05-0.5 MOI RV1B 感染原代 BSMC。两种 dsRNA 刺激物均诱导体外早期（3 h）、浓度依赖性 IFN-β 和 IFN-λ1 mRNA 表达，24 h 时 dsRNA/LyoVec 刺激的表达更高，dsRNA 刺激的表达更低。这种效应可被地塞米松抑制。此外，dsRNA 和 dsRNA/LyoVec 浓度依赖性地上调了 RIG-I 和 MDA5 mRNA 和蛋白。dsRNA 和特别是 dsRNA/LyoVec 导致 IFN-β 和 IFN-λ1 蛋白产生（24 h）。dsRNA-但不是 dsRNA/LyoVec 诱导的 IFN 表达部分被氯喹抑制，氯喹可抑制内体 TLR3 激活。RV1B 剂量依赖性地增加了 BSMC 中 RIG-I、MDA5、IFN-β 和 IFN-λ1 mRNA 的表达。我们认为 BSMC 表达功能性 RLR，并且 RLR 和 TLR3 均参与病毒刺激诱导的 BSMC 中 IFN-β 和 IFN-λ1 的表达。
