IL1B and rheumatoid arthritis: Pathway enrichment analysis indicates oxidative phosphorylation and endocytosis as key signaling pathways in the TREM2highVSIG4+ macrophage population while the inflammatory IL-1B+CCL20+ macrophages enriched in RA synovial tissue display enrichment of signaling pathways such as cell adhesion, antigen processing, and presentation in addition to key inflammatory signaling pathways (NF-κB and PI3K signaling; fig.