Autoantibody profiles and their association with blood eosinophils in asthma and COPD.
BACKGROUND
Autoimmune involvement in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD) has been proposed, and autoantibodies are a hallmark of autoimmunity. This study aimed to compare the autoantibody profiles of asthma and COPD, and the relationship between autoantibodies and features of these diseases.


METHODS
We recruited 110 asthma patients and 92 COPD patients for a prospective study. Six autoantibody types were evaluated: antinuclear antibody, anti-cytoplasmic antibodies, rheumatoid factor, anti-cyclic citrullinated peptide antibody, myeloperoxidase-anti-neutrophil cytoplasmic autoantibody (MPO-ANCA) and proteinase 3-ANCA. Other clinical data were also recorded concurrently.


RESULTS
An antinuclear antibody titre of ≥1:160 presented only in asthma but not in COPD (10% vs. 0%, p = 0.0002). Eosinophil counts in blood were negative predictors of antinuclear antibody in asthma. Conversely, eosinophil counts in blood and immunoglobulin-E levels of ≥100 IU/mL were positively associated with rheumatoid factor in asthma but not in COPD. There was no relationship between antinuclear antibody or rheumatoid factor and disease severity.


CONCLUSIONS
It is possible that asthma tends to involve autoimmunity associated with antinuclear antibody more frequently than COPD because asthma is the more robust factor for antinuclear antibody positivity. Antinuclear antibody and rheumatoid factor are associated with eosinophilic responses, but they do not work as biomarkers for disease severity.
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan. Electronic address: koji.tamai@gmail.com.
Koji
K
Tamai
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Harukazu
H
Yoshimatsu
Department of Rheumatology, Institute for Medical Research, Kobe, Japan.
Toshiharu
T
Saito
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Hirofumi
H
Matsuoka
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Nobuhiko
N
Okada
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Yasuko
Y
Koma
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Akiko
A
Otsuka
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Nao
N
Oda
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Sayaka
S
Inoue
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Sachie
S
Kume
Department of Respiratory Medicine, Shinko Hospital, Kobe, Japan.
Yujiro
Y
Suzuki
D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000097:blood* / Q000175:diagnosis / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D015415:Biomarkers; D004804:Eosinophils; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood* / Q000175:diagnosis / Q000276:immunology*; D012129:Respiratory Function Tests; D012307:Risk Factors
D001323:Autoantibodies; D015415:Biomarkers
Antibody; Asthma; Chronic obstructive pulmonary disease; Eosinophils; Rheumatoid factor