Three more proteins were differently expressed in pSS with respect to sSS (Table 4): lipocalin [UniProtKB:P31025] and rheumatoid factor D5 light chain [UniProtKB:A0N5G5] which were respectively increased and decreased in RA-sSS, and Cystatin C [UniProtKB:P01034], which was significantly reduced in SSc-sSS. Here, CST3 is linked to rheumatoid arthritis.