Increase of interferon-γ inducible α chemokine CXCL10 but not β chemokine CCL2 serum levels in chronic autoimmune thyroiditis

Objective: To measure serum levels of CXCL10 and CCL2 prototype chemokines of the two major sub-class (CXC and CC) in patients with newly diagnosed chronic autoimmune thyroiditis (AT), and relate the findings to the clinical phenotype. Design and methods: Serum CXCL10 and CCL2 were assayed in 70 consecutive patients with newly diagnosed chronic AT, in sex- and age-matched healthy volunteers (n = 37) and in 20 patients with non-toxic multinodular goiter, extracted from a random sample of the general population from the same geographic area. Results: CXCL10 serum levels were significantly higher in patients with thyroiditis than in controls or multinodular goiter patients, while comparable CCL2 levels were found between groups. CXCL10 levels were significantly increased in hypothyroid patients and in those with an hypoechoic pattern (P = 0.0004 and P = 0.0001, respectively) while serum CCL2 levels were significantly increased in patients older than 50 years and in those with hypothyroidism (P = 0.0001 and P = 0.03, respectively). No correlation between CXCL10 and CCL2 serum levels could be demonstrated. CXCL10 and CCL2 were studied separately in relation to clinical features of AT patients. Two separate multiple linear regression models for CXCL10 and CCL2 were performed, including age, thyroid volume, thyroid stimulating hormone (TSH), FT4, anti-thyroid peroxidase (AbTPO), hypoechoic pattern, and the presence of hypervascularity, demonstrating that In of serum CXCL10 levels was associated with TSH independently of other possible confounders levels [regression coefficient (R.C.) 0.143 confidence interval (C.I.) (0.042-0.245); P = 0.0059], while serum CCL2 were significantly associated only with age [R.C. 5.412 C.I. (3.838-6.986); P <0.0001]. Conclusion: Our results, obtained in a large cohort of newly diagnosed AT patients demonstrate increased CXCL10 especially in hypothyroid patients with a more aggressive disorder, and normal CCL2 serum levels in AT.