Cutaneous lupus erythematosus (CLE) is a complex autoimmune condition with limited data on its molecular underpinnings. Saliva, as plasma filtrate fluid may be a promising tool for biomarkers discovery, given its easy accessibility.
Objective
This study aimed to characterize the salivary proteomic profile of CLE patients compared to healthy controls to identify potential disease-specific biomarkers.
Methods
Ten females diagnosed with CLE and eleven controls without autoimmune conditions were included in the study. Saliva samples were collected under controlled conditions and analysed using mass spectrometry and chromatography, performed with the nanoElute nanoflow system coupled to a timsTof-Pro mass spectrometer.
Results
Among the 104 proteins identified, six showed statistically significant differences between groups. PEBP1 (RKIP), ARG1, TALDO, and CTSZ were upregulated in CLE, while TFF3 and PRDX4 were absent. PEBP1 and ARG1 showed high discriminatory power (AUROC = 1.0), suggesting their potential as CLE biomarkers. Data are available via ProteomeXchange with identifier PXD064580.
Conclusion
This study establishes a distinct salivary proteomic signature in CLE, highlighting proteins with diagnostic potential. Saliva proteomics offers a powerful approach to unravel CLE pathophysiology supporting future research on non-invasive biomarkers for disease monitoring and personalized care.
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