Serum Human β-Defensin 2 Is Increased in Angioedema Accompanying Chronic Spontaneous Urticaria

Abstract

Introduction: Chronic spontaneous urticaria (CSU) is a common cutaneous disease caused by mast-cell degranulation. Human β-defensin 2 (HBD2) is a well-known antimicrobial peptide that is also a pruritogen inducing vascular permeability via non-IgE-mediated mast-cell degranulation. Objective: We investigated the associations between serum HBD2 levels and the clinical characteristics of CSU patients. Methods: Serum samples from 124 CSU patients and 56 healthy controls were screened for the levels of HBD2 and translationally controlled tumor protein (TCTP)_ by using ELISA. The urticaria activity score over 7 days (UAS7) was used to measure disease activity in CSU patients. Accompanying angioedema was self-reported. Results: Serum HBD2 levels were higher in the CSU group than in healthy subjects (median [interquartile range], 84.1 [43.5, 142.5] vs. 59.5 [26.7, 121.5], p = 0.034). In CSU patients, serum HBD2 level was negatively correlated with the peripheral basophil percentages (Spearman's rho =-0.229, p = 0.01) and vitamin D levels (-0.262, p = 0.02), but positively correlated with TCTP levels (0.252, p = 0.006). In CSU patients, HBD2 level was higher in those with than without angioedema (101.7 [50.9, 184.2] vs. 66.7 [37.9, 132.0], p = 0.019). It did not differ by aspirin hypersensitivity or atopy status, or autologous serum skin test positivity. Conclusion: A known mast-cell degranulator, HBD2 was elevated in the sera from CSU patients compared to healthy controls and may be involved in the pathogenesis of accompanying angioedema.