Serum soluble interleukin-2 receptor as a biomarker in immunoglobulin G4-related disease

Mod Rheumatol. 2018 Sep;28(5):838-844. doi: 10.1080/14397595.2017.1416739. Epub 2018 Jan 8.


Objectives: Serum soluble interleukin-2 (IL-2) receptor (sIL-2R) might reflect disease activity in immunoglobulin G4-related disease (IgG4-RD). We aimed to elucidate the clinical significance of blood markers, including sIL-2R, in patients with IgG4-RD.

Methods: We enrolled 59 patients with IgG4-RD and investigated the association between blood markers (white blood cells, C-reactive protein, sIL-2R, IgG, IgG4, IgE, total hemolytic complement), and clinical indices.

Results: At baseline, serum sIL-2R (Rs = 0.532, p < .001) and IgG4 (Rs = 0.545, p < .001) levels showed significant correlation to the number of organs involved. During follow-up period (median, 70 months; range, 7-195 months), 40 patients were treated with corticosteroids. Receiver operating characteristic (ROC) analysis showed that baseline sIL-2R levels most accurately predicted patients requiring glucocorticoid treatment (area under the ROC curve, 0.807). Among the 46 patients who improved, sIL-2R and IgG4 levels decreased in 42 and 41 patients, respectively. Among them, serum sIL-2R levels decreased to a normal range in 42 patients (91%), whereas IgG4 levels normalized in 19 (41%).

Conclusion: The serum sIL-2R level is a potential biomarker for IgG4-RD that may reflect the number of involved organs and may predict patients requiring glucocorticoid treatment.

Keywords: Biomarker; IgG4-related disease; soluble IL-2 receptor.

MeSH terms

  • Adult
  • Autoimmune Diseases / blood*
  • Biomarkers / blood
  • Female
  • Humans
  • Immunoglobulin G / blood*
  • Male
  • Middle Aged
  • Receptors, Interleukin-2 / blood*


  • Biomarkers
  • Immunoglobulin G
  • Receptors, Interleukin-2