Serum cytokine profiles of patients with interstitial lung disease associated with anti-CADM-140/MDA5 antibody positive amyopathic dermatomyositis.

BACKGROUND: Patients with amyopathic dermatomyositis (ADM) sometimes develop rapidly progressive interstitial lung disease (ILD) predominantly in Asia. Although anti-CADM-140/MDA5 antibody titer could correlate with disease activity and predict the course of ILD associated with ADM, it is not clear how this antibody is involved in the pathogenesis of ILD in ADM.

METHODS: We retrospectively collected clinical records and preserved serum before treatment of consecutive patients with ADM-ILD treated in the Niigata University Medical and Dental Hospital since 2000. We measured anti-CADM-140/MDA5 antibody titer and compared it between survivors and non-survivors. Serum cytokine/growth factor protein concentration was measured using a multiplex immunoassay system. The associations between anti-CADM-140/MDA5 antibody titer and each cytokine/growth factor protein concentration were evaluated.

RESULTS: Thirteen patients were enrolled into the study. Among them, four patients did not respond to intensive immunosuppressive therapy and died. The mean anti-CADM-140/MDA5 antibody titer was significantly higher in patients who did not responded to therapy than in those who survived (p < 0.05). Relationship analyses between the antibody titer and each cytokine/GF protein concentration revealed that Spearman's rank correlation coefficients were more than 0.4 in thirteen cytokine/GF proteins. In particular, the strongest correlation was found between anti-CADM-140/MDA5 antibody titer and CX3CL1 (r = 0.8897).

CONCLUSIONS: These results confirmed that anti-CADM-140/MDA5 antibody levels could predict outcomes of ADM-ILD. Relationship analyses suggested that CX3CL1 might be involved in the pathogenesis of anti-CADM-140/MDA5 antibody positive ADM-ILD.