Soluble factors released from fibroblast-like synoviocytes of JIA patients with future extended course can condition persistent JIA synovial fibroblasts for increased IL-6 production

Our findings suggest factors secreted by ETB FLS including IL-6 protein may contribute to disease extension. These data highlight the potential role of early synovial signaling in shaping disease trajectory and support further investigation into IL-6 and FLS as possible therapeutic targets to prevent progression.