1st Department of Respiratory Medicine, Medical School of National and Kapodistrian University of Athens, "Sotiria" Hospital of Chest Diseases, Athens, Greece.
2nd Department of Respiratory Medicine, Medical School of National and Kapodistrian University of Athens, "Attikon" Hospital, Athens, Greece.
Respirology. 2017 Apr;22(3):473-479. doi: 10.1111/resp.12937. Epub 2016 Nov 2.
Activin A is a pleiotropic cytokine holding a fundamental role in inflammation and tissue remodelling. Follistatin can modulate the bioactivity of activin. We aimed to measure activin A and follistatin in sputum supernatants and bronchoalveolar lavage (BAL) of asthmatic patients and to determine the possible associations with severity as well as with inflammatory and remodelling indices.
A total of 58 asthmatic patients (33 with severe refractory asthma (SRA)) and 10 healthy controls underwent sputum induction for % cells, activin A, follistatin, eosinophilic cationic protein (ECP), transforming growth factor beta 1 (TGF-β1), IL-13 and IL-8 measurements. In 22 asthmatic patients, BAL and bronchial biopsies were also performed for the assessment of the above-mentioned variables, measurement of remodelling indices and immunostaining for different activin A receptors.
Sputum activin A (pg/mL) was higher in patients with SRA (median (interquartile ranges): 76 (33-185)) compared to mild-to-moderate asthma (44 (18-84); P = 0.005), whereas follistatin did not differ between the two groups. BAL activin A (pg/mL) was higher in patients with SRA compared to those with mild-to-moderate disease. A significant association was observed between activin A and TGF-β1, eosinophils in sputum and/or in BAL, while reticular basement membrane (RBM) thickness was significantly associated with BAL activin levels only. No difference in immunostaining for activin receptor type IB was observed between patients with SRA and those with mild-to-moderate asthma.
Sputum and BAL levels of activin A are higher in SRA. The association of activin A with TGF-β1, eosinophils and RBM thickness may indicate a role of this cytokine in the inflammatory and remodelling process in SRA.
激活素 A 是一种多功能细胞因子，在炎症和组织重塑中起着重要作用。卵泡抑素可调节激活素的生物活性。我们旨在测量哮喘患者的痰上清液和支气管肺泡灌洗液（BAL）中的激活素 A 和卵泡抑素，并确定其与严重程度以及炎症和重塑指标的可能相关性。
共有 58 例哮喘患者（33 例严重难治性哮喘（SRA））和 10 例健康对照者进行了痰液诱导，以测量细胞百分比、激活素 A、卵泡抑素、嗜酸性阳离子蛋白（ECP）、转化生长因子-β1（TGF-β1）、IL-13 和 IL-8。在 22 例哮喘患者中，还进行了 BAL 和支气管活检，以评估上述变量，测量重塑指标，并对不同激活素 A 受体进行免疫染色。
SRA 患者的痰激活素 A（pg/mL）（中位数（四分位间距）：76（33-185））高于轻中度哮喘患者（44（18-84）；P=0.005），而卵泡抑素在两组之间无差异。SRA 患者的 BAL 激活素 A（pg/mL）高于轻中度疾病患者。在痰和/或 BAL 中的激活素 A 与 TGF-β1、嗜酸性粒细胞之间存在显著相关性，而只有 RBM 厚度与 BAL 激活素水平显著相关。在 SRA 患者和轻中度哮喘患者之间，激活素受体类型 IB 的免疫染色无差异。
SRA 患者的痰和 BAL 激活素 A 水平较高。激活素 A 与 TGF-β1、嗜酸性粒细胞和 RBM 厚度的相关性可能表明该细胞因子在 SRA 的炎症和重塑过程中发挥作用。
