Abstract：
Allergen source-derived proteases are a critical factor in the formation and development of asthma. The cysteine protease activity of house dust mite (HDM) disrupts the epithelial barrier function. The expression of cystatin SN (CST1) is elevated in asthma epithelium. CST1 inhibits the cysteine protease activity. We aimed to elucidate the role of epithelium-derived CST1 in the development of asthma caused by HDM.
CST1 protein levels in sputum supernatants and serum of patients with asthma and healthy volunteers were measured by ELISA. The ability of CST1 protein to suppress HDM-induced bronchial epithelial barrier function was examined in vitro. The effects of exogenous CST1 protein on abrogating HDM-induced epithelial barrier function and inflammation were examined in mice in vivo.
CST1 protein levels were higher in sputum supernatants (142.4 ± 8.95 vs 38.87 ± 6.85 ng/mL, P < 0.0001) and serum (1129 ± 73.82 vs 703.1 ± 57.02 pg/mL, P = 0.0035) in patients with asthma than in healthy subjects. The levels were significantly higher in patients with not well- and very poorly controlled asthma than those with well-controlled asthma. Sputum and serum CST1 protein levels were negatively correlated with lung function in asthma. CST1 protein levels were significantly lower in the serum of HDM-specific IgE (sIgE)-positive asthmatics than in sIgE-negative asthmatics. The HDM-induced epithelial barrier function disruption was suppressed by recombinant human CST1 protein (rhCST1) in vitro and in vivo.
Our data indicated that human CST1 protein suppresses asthma symptoms by protecting the asthmatic bronchial epithelial barrier through inhibiting allergenic protease activity. CST1 protein may serve as a potential biomarker for asthma control.
CST1 protein levels in sputum supernatants and serum of patients with asthma and healthy volunteers were measured by ELISA. The ability of CST1 protein to suppress HDM-induced bronchial epithelial barrier function was examined in vitro. The effects of exogenous CST1 protein on abrogating HDM-induced epithelial barrier function and inflammation were examined in mice in vivo.
CST1 protein levels were higher in sputum supernatants (142.4 ± 8.95 vs 38.87 ± 6.85 ng/mL, P < 0.0001) and serum (1129 ± 73.82 vs 703.1 ± 57.02 pg/mL, P = 0.0035) in patients with asthma than in healthy subjects. The levels were significantly higher in patients with not well- and very poorly controlled asthma than those with well-controlled asthma. Sputum and serum CST1 protein levels were negatively correlated with lung function in asthma. CST1 protein levels were significantly lower in the serum of HDM-specific IgE (sIgE)-positive asthmatics than in sIgE-negative asthmatics. The HDM-induced epithelial barrier function disruption was suppressed by recombinant human CST1 protein (rhCST1) in vitro and in vivo.
Our data indicated that human CST1 protein suppresses asthma symptoms by protecting the asthmatic bronchial epithelial barrier through inhibiting allergenic protease activity. CST1 protein may serve as a potential biomarker for asthma control.
摘要：
背景：过敏原来源的蛋白酶是哮喘形成和发展的关键因素。屋尘螨（HDM）的半胱氨酸蛋白酶活性破坏了上皮屏障功能。胱抑素SN（CST1）在哮喘上皮中的表达升高。CST1抑制半胱氨酸蛋白酶活性。我们旨在阐明上皮来源的CST1在HDM引起的哮喘发展中的作用。
方法：用ELISA法检测哮喘患者和健康志愿者痰上清液和血清中CST1蛋白水平。体外检查了CST1蛋白抑制HDM诱导的支气管上皮屏障功能的能力。在小鼠体内检查了外源性CST1蛋白对消除HDM诱导的上皮屏障功能和炎症的影响。
结果：痰上清液中CST1蛋白水平较高（142.4±8.95vs38.87±6.85ng/mL，P<0.0001）和血清（1129±73.82vs703.1±57.02pg/mL，P=0.0035)哮喘患者比健康受试者。与哮喘控制良好的患者相比，哮喘控制不佳的患者的水平明显更高。哮喘患者痰液和血清CST1蛋白水平与肺功能呈负相关。HDM特异性IgE（sIgE）阳性哮喘患者血清中的CST1蛋白水平明显低于sIgE阴性哮喘患者。重组人CST1蛋白（rhCST1）在体外和体内抑制了HDM诱导的上皮屏障功能破坏。
结论：我们的数据表明，人CST1蛋白通过抑制变应原蛋白酶活性保护哮喘支气管上皮屏障来抑制哮喘症状。CST1蛋白可作为哮喘控制的潜在生物标志物。
方法：用ELISA法检测哮喘患者和健康志愿者痰上清液和血清中CST1蛋白水平。体外检查了CST1蛋白抑制HDM诱导的支气管上皮屏障功能的能力。在小鼠体内检查了外源性CST1蛋白对消除HDM诱导的上皮屏障功能和炎症的影响。
结果：痰上清液中CST1蛋白水平较高（142.4±8.95vs38.87±6.85ng/mL，P<0.0001）和血清（1129±73.82vs703.1±57.02pg/mL，P=0.0035)哮喘患者比健康受试者。与哮喘控制良好的患者相比，哮喘控制不佳的患者的水平明显更高。哮喘患者痰液和血清CST1蛋白水平与肺功能呈负相关。HDM特异性IgE（sIgE）阳性哮喘患者血清中的CST1蛋白水平明显低于sIgE阴性哮喘患者。重组人CST1蛋白（rhCST1）在体外和体内抑制了HDM诱导的上皮屏障功能破坏。
结论：我们的数据表明，人CST1蛋白通过抑制变应原蛋白酶活性保护哮喘支气管上皮屏障来抑制哮喘症状。CST1蛋白可作为哮喘控制的潜在生物标志物。
