Cytokines and chemokines are critical components of the immune system and play important roles in autoimmune diseases. Comprehensive profiling of proteins in blood can provide deeper insights into the mechanisms underlying this highly complex and heterogeneous group of diseases. However, many of these proteins are present at very low concentrations in plasma, below the limit of detection of current immunoassays. We recently developed a novel automated multiplex immunoassay technology, NULISA™, capable of attomolar-level sensitivity, and a 200-plex inflammation-focused panel targeting 124 cytokines/chemokines and 80 other important inflammation and immune response-related proteins. We analyzed 21 plasma samples from patients with rheumatoid arthritis (n=5), Sjögren’s syndrome (n=5), systemic lupus erythematosus (n=5), and ulcerative colitis (n=6), and 79 healthy donor samples using the 200-plex NULISAseq™ Inflammation Panel and the Olink Explore 384 Inflammation assay. Differential expression analysis using linear models identified 114 (56%) and 94 (26%) significant targets at a 5% false discovery rate in the NULISAseq and Olink Explore datasets, respectively. Among the 92 targets shared between these two platforms, 54 and 43 significant targets were identified by NULISAseq and Olink, respectively, with 36 in common. Many of the targets identified only by NULISAseq were low-abundance targets that were poorly detected by the Olink assay (IL4, IL5, IL20, IL17A, IL17F, IL33, and IL2RB) but have important roles in autoimmune diseases. In summary, with improved sensitivity and the most comprehensive inflammatory cytokine/chemokine panel, NULISA promises to be a powerful discovery tool for autoimmune disease research, which may lead to new diagnostic biomarkers and therapeutic targets.
