Increased expression of T cell immunoglobulin and mucin domain 4 is positively associated with the disease severity of patients with ankylosing spondylitis.

Monocytes and associated cytokines have been shown to be involved in the pathogenesis of ankylosing spondylitis (AS). T cell immunoglobulin and mucin domain 4 (Tim-4) was identified on monocytes/macrophages and dentritic cells (DCs) and plays important roles in regulating the activities of macrophages and DCs. The current study investigated the association between Tim-4 expression and AS. Our results showed that Tim-4 expression on monocytes and Tim-4 level in plasma were highly increased in AS patients than in controls. Furthermore, TNF-α production and bath ankylosing spondylitis disease activity index (BASDAI) have positive relationships with Tim-4 expression in AS patients. High expression of Tim-4 was thought to contribute to the pathogenesis and an underlying mechanism of AS.