To determine whether interleukin (IL)-33 and soluble ST2 (sST2) are associated with primary Sjogren's Syndrome (pSS).
Serum levels of IL-33 and sST2 in 110 pSS patients and 78 healthy controls were measured by enzyme-linked immunosorbent assay (ELISA). Immunoglobulins, rheumatoid factors (RF), antinuclear antibody (ANA), anti-SSA/RO-52 antibody, anti-SSB antibody and erythrocyte sedimentation rate (ESR) were measured by standard laboratory techniques. Interstitial lung disease (ILD) was identified on high-resolution computed tomography (HRCT). Disease activity in pSS was scored with the European League Against Rheumatism Sjogren's Syndrome Disease Activity Index (ESSDAI).
Serum levels of IL-33 and sST2 were significantly elevated in pSS patients, especially in patients with ILD. There was significant positive correlation between IL-33 and RF, anti-SSB antibody.
IL-33/sST2 may be involved in the pathogenesis of pSS and partly contribute to the ILD in pSS patients.