Supplementary Material for: Elevated CEACAM5 Levels in Patients with Asthma

Introduction: Asthma is a common chronic respiratory disease. This study aimed to explore the expression level of carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) in induced sputum supernatant, induced sputum cells, and serum of asthma patients. Methods: The protein levels of CEACAM5 in induced sputum supernatant and serum were detected by enzyme-linked immunosorbent assay. The expression of CEACAM5 in induced sputum cells was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). We analyzed the correlations between CEACAM5 expression and the clinical characteristics (FeNO and IgE) of asthma. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of CEACAM5 in asthma. The expression level of CEACAM5 in 16HBE and BEAS-2B cells was detected by qRT-PCR. Results: The expression of CEACAM5 in induced sputum supernatant, induced sputum cells, and serum of asthma patients was significantly upregulated. Asthma patients with high CEACAM5 expression in induced sputum supernatant had higher levels of FeNO, IgE, and IL-13. The expression levels of CEACAM5 in induced sputum supernatant and induced sputum cells were positively correlated with FeNO and IgE. The ROC curve showed that CEACAM5 had a good diagnostic value in asthma. CEACAM5 expression was upregulated in BEAS-2B and 16HBE cells after IL-4 or IL-13 stimulation for 48 h. Conclusion: The expression levels of CEACAM5 in induced sputum supernatant, induced sputum cells, and serum of asthma patients were significantly increased. CEACAM5 may be involved in eosinophilic inflammation of asthma and may be used as a diagnostic biomarker and therapeutic target of asthma.

引言：哮喘是一种常见的慢性呼吸系统疾病。本研究旨在探讨癌胚抗原相关细胞黏附分子5（CEACAM5）在哮喘患者诱导痰上清液、诱导痰细胞及血清中的表达水平。
方法：采用酶联免疫吸附试验检测诱导痰上清液与血清中CEACAM5的蛋白水平；采用定量反转录聚合酶链反应（quantitative reverse transcription polymerase chain reaction, qRT-PCR）检测诱导痰细胞中CEACAM5的表达。分析CEACAM5表达与哮喘患者临床特征（呼出气一氧化氮（FeNO）、免疫球蛋白E（IgE））的相关性。采用受试者工作特征（receiver operating characteristic, ROC）曲线分析CEACAM5对哮喘的诊断价值。采用qRT-PCR检测16HBE与BEAS-2B细胞中CEACAM5的表达水平。
结果：哮喘患者诱导痰上清液、诱导痰细胞及血清中的CEACAM5表达均显著上调。诱导痰上清液CEACAM5高表达的哮喘患者，其FeNO、IgE及白细胞介素13（IL-13）水平更高。诱导痰上清液与诱导痰细胞中CEACAM5的表达水平与FeNO、IgE呈正相关。ROC曲线分析显示，CEACAM5对哮喘具有良好的诊断价值。经白细胞介素4（IL-4）或IL-13刺激48小时后，BEAS-2B与16HBE细胞中的CEACAM5表达均上调。
结论：哮喘患者诱导痰上清液、诱导痰细胞及血清中的CEACAM5表达水平均显著升高。CEACAM5可能参与哮喘的嗜酸性粒细胞炎症过程，有望成为哮喘的诊断生物标志物及治疗靶点。