Interleukin-32 Gamma as a New Face in Inflammatory Bone Diseases

ABSTRACT

Interleukin-32 (IL-32), a recently identified pro-inflammatory cytokine, is involved in the pathogenesis and progression of infections, cancer, chronic inflammation, and autoimmune disease. IL-32γ is the most active isoform in cell death and cell activation among nine distinct isoforms of IL-32. IL-32γ potentiates both osteogenic and osteoclastogenic capacities, and is critical in the coupling of bone resorption and bone formation for maintenance of bone homeostasis. IL-32γ is strongly associated with inflammatory bone disorders such as rheumatoid arthritis, ankylosing spondylitis, and osteoporosis. In this review, we summarize current research on the role of IL-32γ in inflammatory bone disorders, highlighting this cytokine as a novel target for prognostic marker and control of these diseases.