Functional KCa3.1 K+ channels are required for human lung mast cell migration
Functional KCa3.1 K+ channels are required for human lung mast cell migration
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DOI：
10.1136/thx.2006.060319
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发表时间：
2006-10-01
期刊：
影响因子：
10
通讯作者：
Bradding, P.
中科院分区：
文献类型：
--
作者：
Cruse, G.;Duffy, S. M.;Bradding, P.
背景：肥大细胞的募集和激活对于炎症和纤维化的发生和发展至关重要。肥大细胞浸润在许多病变组织中的特定结构，例如哮喘中的气道平滑肌（ASM）。肥大细胞的这种微定位可能是疾病发病机制的关键。人肺肥大细胞（HLMC）表达Ca 2+激活的K+通道K（Ca）3.1，其调节介质释放，并被认为在几种细胞类型的迁移过程中促进细胞体的收缩。为验证阻断K（Ca）3.1可抑制HLMC增殖和迁移的假说，进行了一项研究。在药物暴露后的不同时间点通过细胞计数评估HLMC增殖。HLMC趋化性使用标准Transwell室（8 mm孔径）测定。结果：三芳基甲烷-34（Triarylmethane-34，TRAM-34）阻断K（Ca）3.1对HLMC增殖无抑制作用，克霉唑对HLMC有细胞毒作用。与此相反，HLMC迁移趋化因子CXCL 10，趋化干细胞因子，和肿瘤坏死因子刺激哮喘ASM的上清液显着抑制与非选择性K（Ca）3.1阻断剂charybdotoxin和高度特异性K（Ca）3.1阻断剂TRAM-34的剂量依赖性方式。虽然K（Ca）3.1阻断抑制HLMC迁移，但K（Ca）3.1不被趋化刺激打开，这表明它必须参与初始受体-配体相互作用的下游。由于K（Ca）3.1的调节可以抑制HLMC对各种化学引诱物的趋化性，K（Ca）3.1阻断剂如TRAM-34的使用可以为肥大细胞介导的疾病如哮喘提供新的治疗策略。
Background: Mast cell recruitment and activation are critical for the initiation and progression of inflammation and fibrosis. Mast cells infiltrate specific structures in many diseased tissues such as the airway smooth muscle (ASM) in asthma. This microlocalisation of mast cells is likely to be key to disease pathogenesis. Human lung mast cells (HLMC) express the Ca2+ activated K+ channel K(Ca)3.1 which modulates mediator release, and is proposed to facilitate the retraction of the cell body during migration of several cell types. A study was undertaken to test the hypothesis that blockade of K(Ca)3.1 would attenuate HLMC proliferation and migration.Methods: HLMC were isolated and purified from lung material resected for bronchial carcinoma. HLMC proliferation was assessed by cell counts at various time points following drug exposure. HLMC chemotaxis was assayed using standard Transwell chambers (8 mm pore size). Ion currents were measured using the single cell patch clamp technique.Results: K(Ca)3.1 blockade with triarylmethane-34 (TRAM-34) did not inhibit HLMC proliferation and clotrimazole had cytotoxic effects. In contrast, HLMC migration towards the chemokine CXCL10, the chemoattractant stem cell factor, and the supernatants from tumour necrosis factor a stimulated asthmatic ASM was markedly inhibited with both the non-selective K(Ca)3.1 blocker charybdotoxin and the highly specific K(Ca)3.1 blocker TRAM-34 in a dose dependent manner. Although K(Ca)3.1 blockade inhibits HLMC migration, K(Ca)3.1 is not opened by the chemotactic stimulus, suggesting that it must be involved downstream of the initial receptor-ligand interactions.Conclusions: Since modulation of K(Ca)3.1 can inhibit HLMC chemotaxis to diverse chemoattractants, the use of K(Ca)3.1 blockers such as TRAM-34 could provide new therapeutic strategies for mast cell mediated diseases such as asthma.