Circulating levels of soluble interleukin-6 receptor in patients with bronchial asthma.
In the search for markers of airway inflammation, we investigated the role of soluble interleukin-6 receptor (sIL-6R) in patients with bronchial asthma. Serum levels of sIL-6R were measured in 20 patients with stable asthma and in 18 healthy control subjects by means of a sandwich enzyme-linked immunosorbent assay. Such levels were also evaluated during a spontaneous attack of asthma (n = 10) as well as that after allergen inhalation (n = 7). Results were compared with those observed during the stable state and after the inhalation of methacholine. Serum levels of sIL-6R in asthmatic patients (132 +/- 31 ng/ml) significantly exceeded those of control subjects (111 +/- 16 ng/ml) (p < 0.05). These levels showed no correlation with such clinical variables as nonspecific bronchial hyperreactivity, atopic status, or serum concentration of IgE. Serum sIL-6R levels observed during an asthmatic attack versus those during the stable state (4 wk later) differed significantly. After a severe attack of asthma, such levels were significantly elevated on the second and third days, but not on Day 5. After challenge, circulating levels of sIL-6R were significantly increased 24 h after the inhalation of allergen but not of methacholine. Results suggest that serum levels of sIL-6R are increased in patients with asthma and are further increased during a spontaneous attack or that provoked by the inhalation of allergen. Thus, serum sIL-6R may reflect inflammation of the airway. Further studies are indicated to determine the clinical significance and the application of serum levels of sIL-6R in evaluating asthmatic patients.
Yokoyama
A
A
Second Department of Internal Medicine, Ehime University School of Medicine, Japan.
Kohno
N
N
Sakai
K
K
Kondo
K
K
Hirasawa
Y
Y
Hiwada
K
K
D000328:Adult; D000368:Aged; D000485:Allergens / Q000008:administration & dosage; D001249:Asthma / Q000097:blood* / Q000503:physiopathology; D016535:Bronchial Hyperreactivity; D001985:Bronchial Provocation Tests; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage; D008875:Middle Aged; D019947:Receptors, Interleukin-6 / Q000097:blood*; D012995:Solubility
D000485:Allergens; D019947:Receptors, Interleukin-6; D016210:Methacholine Chloride; D007073:Immunoglobulin E