Considering the mean number of spectral counts for the proteins detected in the study groups included in our LC-MS analyses, the three most upregulated proteins in pSS patients (black) that are involved in immunological reactions, when compared to both non-SS subjects (grey) and healthy controls (white), were LMO7, HUWE1, and TPD52, in descending order. Here, HUWE1 is linked to peeling skin syndrome.