IL-17B binds specifically to IL-17RB but not IL-17R . It shares 88% sequence identity between humans and mice , enabling cross-species functional studies.
Proinflammatory Effects: Stimulates TNF-α and IL-1β release in monocytes and IL-8 in hepatocytes .
Anti-inflammatory Modulation: Antagonizes IL-25-driven inflammation in colitis and asthma by suppressing IL-6 production in epithelial cells .
Tissue-Specific Expression: Highly expressed in the spinal cord, brain, and gastrointestinal tract .
IL-17B deficiency exacerbates colitis in mice, increasing neutrophil infiltration and proinflammatory cytokines (e.g., S100A9) in macrophages .
Recombinant IL-17B administration reduces colitis severity by modulating myeloid cell responses .
Upregulated in aggressive breast cancer, promoting tumorigenicity via IL-17RB signaling .
Enhances vascular endothelial cell migration while inhibiting adhesion .
Expressed in bone collars and chondrocytes, influencing skeletal development and fracture repair .
Dual Roles: IL-17B exhibits both pro- and anti-inflammatory effects depending on context .
Therapeutic Targeting: While promising in colitis, its role in cancer and arthritis requires careful modulation .
Mechanistic Gaps: The interplay between IL-17B and other IL-17 family members remains poorly understood .