Decrease of interleukin-10-producing T cells in the peripheral blood of severe unstable atopic asthmatics.
BACKGROUND
Although IL-10 is known as an immunoregulatory cytokine produced by various cells including T cells, its basic profile in atopic asthma remains uncertain.


OBJECTIVE
The profiles of IL-10 production in circulating CD4+ T cells of atopic asthmatics were investigated with respect to clinical severity.


METHODS
Forty atopic asthmatics were divided into three groups: mild, and severe but stable and severe unstable asthmatics. Eosinophils were counted in the peripheral blood and sputum, and exhaled nitric oxide was assessed. PBMCs were stimulated with or without anti-CD3 and anti-CD28 antibodies and then processed for detecting IL-10-producing CD4+ cells using flow cytometry.


RESULTS
There was no difference in the eosinophil count in blood or sputum and in nitric oxide level among the three groups. IL-10-producing CD4+ cells were mainly detected in a CD45RO+ memory population. The frequency of IL-10-producing cells after stimulation was significantly lower in the severe unstable group compared to the mild group. In addition, the frequency of IL-10-producing cells in the severe unstable group was significantly lower than that in the severe stable group despite the fact that both groups received similar treatments with high-dose inhaled corticosteroids. The IL-10 production of CD4+CD45RO+ cells in response to dexamethasone did not differ among the three groups.


CONCLUSIONS
IL-10-producing CD4+CD45RO+ cells in the peripheral blood are decreased in severe unstable asthmatics, which is not explained by the effect of high-dose inhaled corticosteroid medication.
Matsumoto
Koichiro
K
Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. koichi@kokyu.med.kyushu-u.ac.jp
Inoue
Hiromasa
H
Fukuyama
Satoru
S
Tsuda
Miyuki
M
Ikegami
Tomomi
T
Kibe
Atsuko
A
Yoshiura
Yuki
Y
Komori
Masashi
M
Hamasaki
Naotaka
N
Aizawa
Hisamichi
H
Nakanishi
Yoichi
Y
D000328:Adult; D001249:Asthma / Q000378:metabolism* / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D001985:Bronchial Provocation Tests; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D003907:Dexamethasone / Q000008:administration & dosage; D005260:Female; D005434:Flow Cytometry; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D005938:Glucocorticoids / Q000008:administration & dosage; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000378:metabolism / Q000503:physiopathology; D016753:Interleukin-10 / Q000378:metabolism*; D017493:Leukocyte Common Antigens / Q000187:drug effects / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013183:Sputum / Q000737:chemistry / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000378:metabolism
D015415:Biomarkers; D005938:Glucocorticoids; D016753:Interleukin-10; D003907:Dexamethasone; D017493:Leukocyte Common Antigens