Elevated serum RANTES chemokine levels in autoimmune Addison disease

INTRODUCTION    Regulated on activation, normal T‑cell expressed and secreted chemokine (RANTES), the product of the CCL5 gene, is involved in trafficking immune cells into the inflammation site. It acts as coactivator of T cells and promotes polarization of the immune response towards the Th1 profile. In autoimmune Addison disease (AAD), the adrenal cortex is gradually destroyed by adrenal‑specific immune cell infiltration. RANTES might be implicated in autoimmune adrenal failure through recruitment and activation of the immune cells. Furthermore, the promoter CCL5 variant, rs2107538, seems to be associated with autoimmune endocrine conditions: diabetes and thyroid disease. OBJECTIVES    Our analysis was designed to evaluate the prevalence of rs2107538 and serum RANTES levels in AAD. PATIENTS AND METHODS    rs2107538 was genotyped using TaqMan technology in 239 individuals with AAD and 542 controls, while serum RANTES levels were evaluated by an enzyme‑linked immunosorbent assay in 114 patients with AAD and 111 healthy age- and sex‑matched individuals. RESULTS    No differences were found in rs2107538 genotype or allele frequencies between patients and controls (P = 0.53 and P = 0.39, respectively), and no association was detected with age at AAD onset (P = 0.14). Serum RANTES levels were elevated in patients with AAD compared with controls (mean [SD], 59.2 [30.3] ng/ml vs 45.5 [20.4] ng/ml, P = 0.001). Healthy carriers of various rs2107538 genotypes demonstrated differences in serum RANTES levels (P = 0.02), whereas AAD patients did not (P = 0.26). No correlation was found between circulating RANTES levels and age, AAD duration, serum autoantibodies, hydrocortisone dose, and body mass (P >0.05). CONCLUSIONS    This study demonstrates for the first time elevated serum RANTES levels in AAD and confirms that rs2107538 may affect serum chemokine levels.