IL1B and rheumatoid arthritis: Compared to OA, all three macrophage clusters upregulated CXCL2, CXCL1, IL1B, TNFAIP3, ICAM1, CXCL3, PLAU, CCL4L2, CCL4, and TNF within the NF-kappa B signaling pathway.131 This study identifies macrophage subsets with different polarized states and their molecular signatures, providing a more precise understanding of these cell subtypes in RA and OA.