Biomarker

Abstract

Clinical manifestation, disease progress, and prognosis are heterogeneous in each patient with systemic sclerosis (SSc). Therefore, biomarkers that can estimate these matters are essential for clinical practice. Although SSc-specific autoantibodies are very useful markers, other biomarkers have not been established. Regarding potential biomarkers of fibrosis, some cytokines, chemokines, adhesion molecules including connective tissue growth factor, interleukin-6, CCL2, CXCL4, and circulating intercellular adhesion molecule- 1 have been reported. The glycoprotein Krebs von den Lungen-6 and surfactant protein-D are currently the most reliable serum biomarkers of interstitial lung diseases of SSc. Serum or plasma levels of brain natriuretic peptide and N-terminal pro-brain natriuretic peptide have been used as useful biomarkers for SSc-related pulmonary arterial hypertension, although these are not specific for pulmonary arterial hypertension. It has been reported that interferoninducible chemokine score correlated with the Medsger Severity Index, particularly with the severity of the skin, muscle, and lung involvement. Further large multicenter prospective studies will be needed to identify critical biomarkers of SSc.