Center for Tissue and Cell Sciences, Seattle Children's Research Institute, Seattle, WA, USA.
J Allergy Clin Immunol. 2012 Apr;129(4):990-7.e6. doi: 10.1016/j.jaci.2011.11.035. Epub 2012 Jan 9.
The airway epithelium can express factors that drive subepithelial airway remodeling. TGF-β2, vascular epithelial growth factor (VEGF), a disintegrin and metalloprotease 33 (ADAM33), and periostin are hypothesized to be involved in subepithelial remodeling and are overexpressed in adult asthmatic airways. Epidemiologic data suggest that lung function deficits in asthmatic patients are acquired in childhood.
We sought to determine whether airway epithelial cells (AECs) from asthmatic children differentially express TGF-β2, VEGF, ADAM33, or periostin compared with cells from atopic nonasthmatic and healthy children intrinsically or in response to IL-4/IL-13 stimulation.
Bronchial and nasal epithelial cells were obtained from brushings from well-characterized asthmatic (n = 16), atopic nonasthmatic (n = 9), and healthy (n = 15) children after achievement of anesthesia for elective procedures. After differentiation at an air-liquid interface (ALI) for 3 weeks, conditioned media were sampled and RNA was extracted from unstimulated and IL-4/IL-13-stimulated cultures. TGF-β2 and VEGF levels were measured with ELISA. ADAM33 and periostin expression was assessed by using real-time PCR.
TGF-β2 and VEGF production was significantly greater in bronchial and nasal ALI cultures from asthmatic children than in cultures from atopic nonasthmatic and healthy children. TGF-β2 levels increased significantly in asthmatic cultures after IL-4/IL-13 stimulation. Within-subject correlation between nasal and bronchial ALI production of TGF-β2 (r = 0.64, P = .001) and VEGF (r = 0.73, P < .001) was good. Periostin expression was 3.7-fold higher in bronchial cells (P < .001) and 3.9-fold higher in nasal cells (P < .004) from asthmatic children than in cells from atopic nonasthmatic or healthy children. ADAM33 was not differentially expressed by AECs from asthmatic patients compared with that from cells from atopic nonasthmatic or healthy children.
AECs from asthmatic children differentially express TGF-β2, VEGF, and periostin compared with cells from atopic nonasthmatic and healthy children. Nasal epithelial cells might be a suitable surrogate for bronchial cells that could facilitate investigation of the airway epithelium in future longitudinal pediatric studies.
气道上皮细胞可表达驱动黏膜下气道重塑的因子。转化生长因子-β2（TGF-β2）、血管内皮生长因子（VEGF）、解整合素金属蛋白酶 33（ADAM33）和骨粘连蛋白（periostin）被认为参与黏膜下重塑，并在成年哮喘气道中过度表达。流行病学数据表明，哮喘患者的肺功能缺陷是在儿童时期获得的。
我们旨在确定哮喘儿童的气道上皮细胞（AECs）与特应性非哮喘和健康儿童的 AECs 相比，内在或在白细胞介素 4/白细胞介素 13（IL-4/IL-13）刺激下是否差异表达 TGF-β2、VEGF、ADAM33 或骨粘连蛋白。
在进行择期手术的全身麻醉后，从 16 名哮喘儿童、9 名特应性非哮喘儿童和 15 名健康儿童的支气管和鼻刷中获得支气管和鼻上皮细胞。在气液界面（ALI）分化 3 周后，采集条件培养基并从未刺激和 IL-4/IL-13 刺激培养物中提取 RNA。通过 ELISA 测量 TGF-β2 和 VEGF 水平。通过实时 PCR 评估 ADAM33 和骨粘连蛋白的表达。
与特应性非哮喘和健康儿童的培养物相比，哮喘儿童的支气管和鼻 ALI 培养物中 TGF-β2 和 VEGF 的产生显著增加。在 IL-4/IL-13 刺激后，哮喘培养物中的 TGF-β2 水平显著增加。鼻和支气管 ALI 产生的 TGF-β2（r=0.64，P=0.001）和 VEGF（r=0.73，P<0.001）之间的个体内相关性良好。与特应性非哮喘或健康儿童的细胞相比，哮喘儿童的支气管细胞（P<0.001）和鼻细胞（P<0.004）的骨粘连蛋白表达高 3.7 倍。与特应性非哮喘或健康儿童的细胞相比，哮喘患者的 AEC 中 ADAM33 的表达没有差异。
与特应性非哮喘和健康儿童的细胞相比，哮喘儿童的 AEC 中差异表达 TGF-β2、VEGF 和骨粘连蛋白。鼻上皮细胞可能是一种适合支气管细胞的替代物，可促进未来儿科纵向研究中气道上皮的研究。
