The expression levels of IL-4 and IL-13 in the serum and blister fluid of patients with bul-lous pemphigoid
Objective To investigate the expression levels of type 2 inflammatory cytokines,IL-4 and IL-13,in the serum and blister fluid of patients with bullous pemphigoid(BP).Meth-ods The serum or blister fluid was collected from BP patients(49 cases)and healthy individuals(33 cases).ELISA was used to measure the concentrations of IL-4 and IL-13.The expression levels of IL-4 and IL-13 were compared between the BP patients and healthy controls.The correla-tions of IL-4 and IL-13 with total serum IgE levels,eosinophils,skin erythema score and pruritus severity(NRS)in BP patients were analyzed.Moreover,the associations of BP180 and BP230 IgG antibodies with IL-4,IL-13 and total serum IgE levels,and eosinophils were determined.Re-sults The concentrations of IL-4 and IL-13 in the blister fluid,but not in the serum,were signif-icantly higher in the BP patients than in the healthy controls(P<0.01).Serum levels of either IL-4 or IL-13 were not significantly correlated with total serum IgE levels,eosinophils,erythema score and NRS in BP patients.However,IL-4 levels in blister fluid were positively correlated with total serum IgE levels in BP patients(r=0.98,P=0.021).The IL-13 levels in blister fluid were associated with serum BP180 positive,but BP230 negative(r=0.58,P=0.009).Conclu-sions Elevated IL-4 and IL-13 levels in the involved skin site of bullous pemphigoid suggest the present of local type 2 inflammation.Total IgE levels may reflect the severity of local type 2 in-flammation.BP180 complex may affect the development of type 2 inflammation through increasing local IL-13 levels.These findings might be helpful in the target therapy in the future.