IL17RA

Interleukin-17 receptor A (IL17RA), also known as CD217 or IL-17R, is a transmembrane protein that serves as a critical component of the IL-17 receptor complex. It binds interleukin-17A (IL-17A) and related cytokines (IL-17F, IL-17A/F heterodimer), initiating proinflammatory signaling through heterodimerization with IL17RC. This interaction activates downstream pathways, including NF-κB, MAPK, and C/EBP, driving the expression of chemokines (CXCL1, CXCL8) and antimicrobial peptides. IL17RA is essential for host defense against extracellular pathogens but is also implicated in pathological inflammation.
Dysregulated IL17RA signaling is linked to autoimmune disorders such as psoriasis, rheumatoid arthritis, and ankylosing spondylitis. Therapeutic strategies targeting this axis include monoclonal antibodies like brodalumab, a direct IL17RA antagonist approved for moderate-to-severe plaque psoriasis. Small-molecule inhibitors disrupting IL17RA-cytokine interactions are under preclinical investigation, aiming to mitigate systemic side effects associated with biologics. Recent studies also explore its role in cancer-associated inflammation and inflammatory bowel disease, expanding potential therapeutic applications.