Objective: We sought to assess serum cutaneous T-cell-attracting chemokine (CTACK) levels and CTACK expression levels in skin from patients with systemic sclerosis (SSc), and determine whether serum CTACK levels correlate with clinical features in SSc patients.
Methods: Serum samples were obtained from 73 SSc patients, 32 patients with systemic lupus erythematosus and 26 patients with dermatomyositis. Serum CTACK levels were determined by enzyme-linked immunoabsorbent assay. CTACK mRNA expression in sclerotic skin was assessed by real-time reverse transcription-polymerase chain reaction.
Results: Serum CTACK levels were significantly increased in patients with diffuse cutaneous SSc (dSSc; n=32) and those with limited cutaneous SSc (lSSc; n=41) compared with normal controls (n=31; P<0.05 and P<0.0005, respectively). The presence of calcinosis and muscle involvement was more frequently detected in SSc patients with elevated CTACK levels (P<0.05 and P<0.05, respectively). Elevated C-reactive protein levels were also observed more frequently in SSc patients with increased CTACK levels (P<0.05). CTACK mRNA expression levels in the sclerotic skin of SSc patients were augmented. In a longitudinal study, serum CTACK levels were generally decreased during the follow-up.
Conclusions: The increased serum CTACK levels and enhanced skin CTACK expression in SSc patients suggest that CTACK is related to the inflammation associated with SSc.