Figure 4: Median and interquartile range of GCDFP-15/PIP optical density of patients and healthy controls (p<0.0001 by ANOVA analysis). GCDFP-15/PIP is differently expressed between primary Sjögren’s syndrome patients (pSS) and non-SS sicca syndrome patients (CTL), with p=0.01 (*), and between pSS and healthy control subjects (HC), with p<0.0001 (***).