Interleukin-31 (IL-31) is a cytokine primarily produced by activated T cells, particularly Th2 cells, and is implicated in pruritus (itching) and inflammatory skin diseases. It signals through a receptor complex composed of IL-31 receptor alpha (IL-31RA) and oncostatin M receptor beta (OSMRβ), activating pathways like JAK/STAT, which drive inflammation and sensory nerve stimulation. Dysregulated IL-31 expression is linked to chronic pruritic conditions, including atopic dermatitis (AD), allergic contact dermatitis, and prurigo nodularis.
IL-31-targeting antibodies, such as anti-IL-31 or anti-IL-31RA monoclonal antibodies, aim to neutralize IL-31 signaling to alleviate itching and skin inflammation. For example, nemolizumab, an anti-IL-31RA antibody, has shown efficacy in clinical trials for AD, significantly reducing pruritus and lesion severity. These therapies offer a targeted approach compared to broad immunosuppressants, potentially minimizing systemic side effects. Research continues to explore their long-term safety, broader applications in eosinophilic disorders, and combination strategies with other biologics. IL-31 antibodies represent a promising frontier in managing chronic pruritic diseases, addressing both symptoms and underlying inflammation.