Targeting interleukin 4 and interleukin 13: a novel therapeutic approach in bullous pemphigoid

Aim: Bullous pemphigoid (BP) is an organ-specific autoimmune bullous disease characterized by autoantibodies that target the cellular adhesion molecules BP180 and BP230. Both immunoglobulin (Ig)G and IgE are involved in the induction of subepidermal blisters. Specifically, IgE autoantibodies are presumed to be responsible for the pruritic and erythematous features of BP. Histologically, eosinophil infiltration is a prominent feature in BP. Eosinophils and IgE are mostly associated with the Th2 immune response. Th2 cytokines, particularly interleukin (IL)-4 and IL-13, are presumed to contribute to the pathology of BP. The aim of this review is to discuss the role of IL-4/13 in the pathogenesis of BP and the potential of using IL-4/13 antagonists for treatment.Methods: After searching in PubMed and Web of Science databases using 'bullous pemphigoid', 'interleukin-4/13', and 'dupilumab' as keywords, studies related was compiled and examined.Results: Overall, IgE, eosinophils, IL-4, and IL-13 may interact with each other in the pathogenesis of BP; these potential interactions provide clues concerning targets for molecular treatment.Conclusion: Anti-IL-4/13 treatment has been experimentally used in patients with BP, with satisfactory outcomes and few side effects. However, before this novel therapy can be approved for regular usage, further studies are needed concerning the long-term safety and systemic usage of IL-4/13 monoclonal antibody treatment in BP. KEY MESSAGES BP is an autoimmune skin disease with Th2-mediated autoimmune response involvement. As typical Th2 cytokines, IL-4 and IL-13 may contribute to the pathogenesis of BP in multiple ways, such as promoting Th2 cell polarization, driving the immunoglobulin class switching, recruiting eosinophils and basophils, and inducing pruritus. As a promising therapeutic approach for BP, IL-4/13 antagonists have shown satisfactory outcomes in preliminary clinical studies.