Recombinant anti-IL-4Rα nanobody(Shanghai Novamab Biopharmaceuticals)

Treatment of severe eczema in patients with primary immunodeficiencies can be particularly challenging as there are no guidelines with regards to these conditions. Dupilumab is an interleukin (IL)‐4Rα antagonist that inhibits both IL‐4 and IL‐13 and is approved for the treatment of atopic dermatitis in pediatric patients. In this report, we describe a patient with a case of severe eczema in the context of Wiskott–Aldrich syndrome‐related disorder, who was successfully treated with dupilumab.

The present study aimed to evaluate the suppressive function of dupilumab and baricitinib on FcεRI-mediated human basophil activation in vitro.In line with previous reports, significant basophil infiltration was detected in the lesional skin of AD patients but not in the skin of healthy donors.Results from flow cytometric intracellular phosphoprotein staining demonstrated that the JAK1/2 inhibitor, but not dupilumab, specifically suppressed the activation of STAT3, an essential mol. in the JAK-STAT pathway.Western blot anal. confirmed that the JAK1/2 inhibitor suppressed the activation of STAT3 as well as FcεRI-mediated activation of Syk and PKC, indicating the JAK1/2 inhibitor suppresses basophil activation and degranulation via FcεRI-mediated signaling.Our study confirmed skin infiltration of basophils in the lesional skin of AD patients.Our results suggested that baricitinib may exert its anti-pruritic function by suppressing the activation of skin-infiltrating basophils in AD patients.Although the IL-4Rα antagonist did not display its suppressive function on basophil activation in our in vitro experiments, it is still possible that the IL-4Rα antagonistic biologics exert an indirect suppressive function on basophils through suppression of the activation of Th2 cells in vivo.The suppressive function of the JAK1/2 inhibitor baricitinib on activated basophils demonstrated here in vitro might be responsible for the fast and strong effect of.JAK inhibitors including baricitinib on allergic skin inflammation and skin lesions in AD patients observed in clin. studies.