However, its expression is upregulated in rheumatoid arthritis (167–169), ankylosing spondylitis (170), Grave’s disease (171), and systemic lupus erythematosus (172–174), with a relatively lower IL-37 level correlating with higher disease activity (175); this indicates the potential anti-inflammatory effect of IL-37 against inflammatory situations. Here, IL37 is linked to ankylosing spondylitis.