title: Expression levels of eosinophil granule protein mRNAs in induced sputum reflect airway hyperresponsiveness and airflow limitation.
abstract: Eosinophils are regarded as the major effector cells that produce symptoms in allergic diseases. Activation of eosinophils induces extracellular release of a number of eosinophil granule proteins, including major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil peroxidase (EPO), and eosinophil-derived neurotoxin. The objective of this study was to evaluate the differences and significance of the sputum eosinophil% and expression levels of eosinophilic granule protein mRNAs in allergic airway disease. Induced sputum samples were obtained from non-smokers with 25 asthma, 54 eosinophilic bronchitis, 16 allergic rhinitis, and 19 healthy control subjects. The eosinophil granule protein mRNAs were measured with real time RT-PCR. There was no correlation between the sputum eosinophil% and the mRNA level of any of eosinophil granule proteins. However, the expression levels of MBP and ECP mRNAs were higher in subjects with each of the specified allergic diseases than those in control subjects (P < 0.05). Moreover, in the subjects with allergic sensitization, the expression levels of MBP and EPO mRNAs were significantly higher in those with airway hyperresponsiveness (13 subjects) than in those without airway hyperresponsiveness (32 subjects) (P = 0.004 and 0.010, respectively). In asthma patients, the FEV1% was negatively correlated with ECP mRNA levels (r = -0.510, P = 0.022), but showed no correlation with sputum eosinophil%. In conclusion, mRNA levels of eosinophil granule proteins, rather than sputum eosinophil%, may reflect airway hyperresponsiveness and airflow limitation. In practice, consideration for the eosinophil% as well as the eosinophil granule proteins levels in induced sputum is needed.
authors.affiliation: Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center.
authors.forename: Jae-Woo
authors.initials: JW
authors.lastname: Jung
authors.forename: Hye-Ryun
authors.initials: HR
authors.lastname: Kang
authors.forename: Hyun-Seung
authors.initials: HS
authors.lastname: Lee
authors.forename: Heung-Woo
authors.initials: HW
authors.lastname: Park
authors.forename: Sang Heon
authors.initials: SH
authors.lastname: Cho
authors.forename: Kyung-Up
authors.initials: KU
authors.lastname: Min
authors.forename: Seong-Wook
authors.initials: SW
authors.lastname: Sohn
mesh_terms: D000328:Adult; D001249:Asthma / Q000097:blood / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000097:blood / Q000235:genetics* / Q000503:physiopathology*; D001991:Bronchitis / Q000097:blood / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D016022:Case-Control Studies; D003710:Demography; D047091:Eosinophil Granule Proteins / Q000235:genetics* / Q000378:metabolism; D004804:Eosinophils / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D012123:Pulmonary Ventilation / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D065631:Rhinitis, Allergic / Q000097:blood / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D013183:Sputum / Q000378:metabolism*
chemical_list: D047091:Eosinophil Granule Proteins; D012333:RNA, Messenger