Objectives: To measure serum levels of CXCL10 and CCL2 chemokines in patients with SSc, and relate the findings to clinical phenotype and disease progression.
Methods: Serum CXCL10 and CCL2 were assayed in 72 consecutive newly diagnosed SSc patients and in 72 sex- and age-matched controls. In 37 SSc and 37 controls, serum CXCL10 and CCL2 were re-evaluated 5 yrs later.
Results: SSc at onset showed significantly higher CXCL10 serum levels than controls (216 +/- 126 vs 92 +/- 53 pg/ml; P < 0.0001), as well as CCL2 (388 +/- 172 vs 318 +/- 120 pg/ml; P = 0.01). CXCL10 was significantly increased in SSc with interstitial lung involvement or with kidney involvement (P = 0.01 and P = 0.02, respectively). A significant decrease of CXCL10 was observed from the baseline after 5 yrs in SSc (137 +/- 112 vs 270 +/- 122 pg/ml, respectively; P < 0.0001), while no significant change was observed for CCL2 (418 +/- 176 vs 405 +/- 164 pg/ml; P = NS); the CCL2/CXCL10 ratio significantly increased at the fifth year (1.7 +/- 0.8 vs 3.5 +/- 2.5; P < 0.0001). No significant variations were observed in controls from the basal to the 5-yr evaluation with regards to CXCL10, CCL2 or CCL2/CXCL10 ratio.
Conclusions: Our study demonstrates high serum levels of CXCL10 (Th1) and CCL2 (Th2) chemokines in newly diagnosed SSc. High values of CXCL10 are associated with a more severe clinical phenotype (lung and kidney involvement). CXCL10 declined during the follow-up, while CCL2 remained unmodified, suggesting that the disease progresses from the early Th1 inflammatory condition to the advanced Th2-like stage.