Asthmatic Airway Epithelium Is Intrinsically Inflammatory and Mitotically Dyssynchronous
Asthmatic Airway Epithelium Is Intrinsically Inflammatory and Mitotically Dyssynchronous
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DOI：
10.1165/rcmb.2010-0029oc
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发表时间：
2011-06-01
影响因子：
6.4
通讯作者：
Hoffman, Eric P.
中科院分区：
文献类型：
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作者：
Freishtat, Robert J.;Watson, Alan M.;Hoffman, Eric P.
哮喘是一种炎症性疾病，抗炎糖皮质激素是标准治疗方法。然而，针对炎症细胞和通路的药物尚未显示出类似的功效。这表明非炎症细胞（例如上皮细胞）导致哮喘炎症。在此，我们试图确定哮喘气道上皮与正常上皮相比的内在特性和糖皮质激素影响的特性。从 248 小时开始，在不含糖皮质激素的培养基中培养人原代分化的正常和哮喘气道上皮。他们在-26、-2、+22和+46小时用地塞米松(20nM)或媒介物脉冲2小时。在 0 小时时对培养物进行机械刮伤并连续暴露于溴脱氧尿苷 (BrdU)。使用细胞计数珠测定法分析细胞因子分泌物。通过显微镜和流式细胞术分析伤口再生/有丝分裂。静止的正常（n = 3）和哮喘（n = 6）上皮细胞显示出相似的最小炎症细胞因子分泌和有丝分裂指数。受伤后，哮喘上皮分泌更多的基底外侧 TGF-β 1、IL-10、IL-13 和 IL-1 β（P < 0.05），并且再生效率低于正常上皮（+48 小时伤口面积减少 = [平均值 +/- SEM] 50.2 +/- 7.5% 对比 78.6 +/- 7.7%；P = 0.02）。哮喘上皮细胞在 +48 小时时 BrdU(+) 细胞减少 40%（总细胞数为 0.32 +/- 0.05% 与 0.56 +/- 0.07%；P = 0.03），并且这些细胞在细胞周期中的分布更加不同步（G1/G0、S 和 G2/M 为 52 +/- 10、25 +/- 4、23 +/- 7%，分别）比正常上皮细胞（G1/G0、S 和 G2/M 分别为 71 +/- 1、12 +/- 2 和 17 +/- 2%）。地塞米松脉冲改善了哮喘上皮炎症和再生/有丝分裂。总之，我们表明炎症/纤维化细胞因子分泌与损伤时不同步的有丝分裂相关。间歇性糖皮质激素同时减少上皮细胞因子分泌并重新同步有丝分裂。这些数据是在缺乏炎症细胞的气道模型中生成的，支持上皮细胞导致哮喘炎症的概念。
Asthma is an inflammatory condition for which anti-inflammatory glucocorticoids are the standard of care. However, similar efficacy has not been shown for agents targeting inflammatory cells and pathways. This suggests a noninflammatory cell contributor (e. g., epithelium) to asthmatic inflammation. Herein, we sought to define the intrinsic and glucocorticoid-affected properties of asthmatic airway epithelium compared with normal epithelium. Human primary differentiated normal and asthmatic airway epithelia were cultured in glucocorticoid-free medium beginning at 248 hours. They were pulsed with dexamethasone (20nM) or vehicle for 2 hours at -26, -2, +22, and +46 hours. Cultures were mechanically scrape-wounded at 0 hours and exposed continuously to bromodeoxyuridine (BrdU). Cytokine secretions were analyzed using cytometric bead assays. Wound regeneration/mitosis was analyzed by microscopy and flow cytometry. Quiescent normal (n = 3) and asthmatic (n = 6) epithelia showed similar minimal inflammatory cytokine secretion and mitotic indices. After wounding, asthmatic epithelia secreted more basolateral TGF-beta 1, IL-10, IL-13, and IL-1 beta (P < 0.05) and regenerated less efficiently than normal epithelia (+48 h wound area reduction = [mean +/- SEM] 50.2 +/- 7.5% versus 78.6 +/- 7.7%; P = 0.02). Asthmatic epithelia showed 40% fewer BrdU(+) cells at +48 hours (0.32 +/- 0.05% versus 0.56 +/- 0.07% of total cells; P = 0.03), and those cells were more dyssynchronously distributed along the cell cycle (52 +/- 10, 25 +/- 4, 23 +/- 7% for G1/G0, S, and G2/M, respectively) than normal epithelia (71 +/- 1, 12 +/- 2, and 17 +/- 2% for G1/G0, S, and G2/M, respectively). Dexamethasone pulses improved asthmatic epithelial inflammation and regeneration/mitosis. In summary, we show that inflammatory/fibrogenic cytokine secretions are correlated with dyssynchronous mitosis upon injury. Intermittent glucocorticoids simultaneously decreased epithelial cytokine secretions and resynchronized mitosis. These data, generated in an airway model lacking inflammatory cells, support the concept that epithelium contributes to asthmatic inflammation.