OBJECTIVE: To identify biomarkers that distinguish psoriatic arthritis (PsA) from cutaneous psoriasis without arthritis (PsC) and healthy controls (HC) using single cell RNA sequencing (scRNA-seq). METHOD: Peripheral blood mononuclear cell samples from three patients with PsA fulfilling CASPAR criteria, three patients with PsC and two HC were profiled using scRNA-seq. Differentially expressed genes (DEGs) identified through scRNA-seq were validated on classical monocytes, and CD4 RESULTS: A total of 18 immune cell population clusters were identified. Across 18 cell clusters, we identified 234 DEGs. CONCLUSION: These results suggest that translation of