Figure 3From: Epistasis with HLA DR3 implicates the P2X7 receptor in the pathogenesis of primary Sjögren's syndromeBoxplots of serum IL-18 levels (pg/mL) in controls ( n = 36), autoantibody negative pSS ( n = 18), and autoantibody positive primary Sjögren's syndrome (pSS) ( n = 54). Serum IL-18 levels were significantly different between the three groups (P = 0.0003, Kruskal-Wallis test), and highest in autoantibody-positive pSS.Back to article page