828 Targeted proteomics and spectral flow cytometry analysis of cutaneous lupus erythematosus

Cutaneous Lupus Erythematosus (CLE) is an inflammatory skin disease characterized by perivascular and periadnexal lymphohistiocytic infiltrate interface dermatitis. Using suction blister biopsies of lesional nonlesional from four CLE patients three healthy donors, we did spectral flow cytometry to study the immune cells infiltrating cytokines in interstitial fluid. We identified a significant increase HLA-DR+antigen-presenting (P<0.0001) compared controls. detected presence T-cells, B-cells, natural killer cells, plasmacytoid dendritic key cell populations thought drive immunopathogenesis. found different clusters expressing CXCR3 skin, while total frequency MFI CXCR3+cells were not significantly CLE. Further, measured 184 protein analytes fluid using targeted proteomics. Our data confirmed elevation chemokine ligands previously reported highly inflamed CXCL9 CXCL11 (P=0.0007), validating biopsy as minimally invasive method monitor activity. potential novel biomarkers, including CASP8 (P=0.002), CTF1 (P=0.01), HGF (P=0.0005), Flt3L (P<0.0001), IFNL1 (P=0.02), CXCL6 CCL25 (P=0.005), CCL28 (P=0.03) that are increased healthy. uncovered proteins with concentration clinically normal patients, which may define preclinical stage disease. These differentially expressed (DEPs) between controls included (0.01), (P=0.003), decreased CEACAM3 (P=0.0002). hypothesize these serve early activity biomarkers or predictors progression.