Serum interferon-α is a useful biomarker in patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis.
OBJECTIVE
We have tried to clarify the clinical importance of the measurement of serum type-I interferon (IFN) in patients with anti-melanoma differentiation-associated gene 5 Ab (MDA5 Ab)-positive dermatomyositis (DM).


METHODS
We studied 30 patients with DM: 10 were anti-MDA5 Ab-positive and 20 were anti-MDA5 Ab-negative. At each patient's initial visit, serum IFN-α, IFN-β, interleukin 18 (IL-18), ferritin, and the titer of anti-MDA5 Ab were measured using enzyme-linked immunosorbent assays (ELISAs). The associations between the IFNs and with the other variables were examined.


RESULTS
Rapidly progressive interstitial lung disease (RPILD) was confirmed in 10 patients, most of whom were complicated in the anti-MDA5 Ab-positive DM patients. The presence of clinically amyopathic dermatomyositis (CADM) as well as the serum concentrations of IFN-α and ferritin was significantly higher in the anti-MDA5 Ab-positive DM patients. Serum concentration of IL-18 did not differ between anti-MDA5 Ab-positive and anti-MDA5 Ab-negative groups; however, a positive correlation was found between IFN-α and IL-18 in the anti-MDA5 Ab-positive DM patients (r = 0.8139, p = 0.0146).


CONCLUSIONS
Serum IFN-α can be used as a useful biomarker in patients with anti-MDA5 Ab-positive DM, which may reflect the presence of RPILD.
Unit of Translational Medicine, Department of Immunology and Rheumatology, Nagasaki University Graduate School of Biomedical Sciences , Nagasaki , Japan.
Yoshiro
Y
Horai
Tomohiro
T
Koga
Keita
K
Fujikawa
Ayuko
A
Takatani
Ayako
A
Nishino
Yoshikazu
Y
Nakashima
Takahisa
T
Suzuki
Shin-ya
SY
Kawashiri
Naoki
N
Iwamoto
Kunihiro
K
Ichinose
Mami
M
Tamai
Hideki
H
Nakamura
Hiroaki
H
Ida
Tomoyuki
T
Kakugawa
Noriho
N
Sakamoto
Yuji
Y
Ishimatsu
Hiroshi
H
Mukae
Yasuhito
Y
Hamaguchi
Manabu
M
Fujimoto
Masataka
M
Kuwana
Tomoki
T
Origuchi
Shigeru
S
Kohno
Atsushi
A
Kawakami
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D053487:DEAD-box RNA Helicases / Q000276:immunology*; D003882:Dermatomyositis / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D000072640:Interferon-Induced Helicase, IFIH1; D016898:Interferon-alpha / Q000097:blood*; D020382:Interleukin-18 / Q000097:blood; D017563:Lung Diseases, Interstitial / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D055815:Young Adult
D001323:Autoantibodies; D015415:Biomarkers; D016898:Interferon-alpha; D020382:Interleukin-18; D005293:Ferritins; C452815:IFIH1 protein, human; D053487:DEAD-box RNA Helicases; D000072640:Interferon-Induced Helicase, IFIH1
CADM; Ferritin; IFN-α; RPILD; anti-MDA5 antibody