IL36B and rheumatoid arthritis: Focusing on autoimmune arthritis IL-36β (IL-1F8), another family member, induced the expression of IL-6, IL-8 and nitric oxygen (NO) in primary synovial fibroblasts; however, the level of IL-36β in serum and synovial fluid of patients with rheumatoid arthritis, osteoarthritis and septic shock did not correlate with the grade of inflammation [8].