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

Abstract

<b><i>Introduction:</i></b> 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. <b><i>Objective:</i></b> We investigated the associations between serum HBD2 levels and the clinical characteristics of CSU patients. <b><i>Methods:</i></b> 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. <b><i>Results:</i></b> 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], <i>p</i> = 0.034). In CSU patients, serum HBD2 level was negatively correlated with the peripheral basophil percentages (Spearman’s rho = −0.229, <i>p</i> = 0.01) and vitamin D levels (−0.262, <i>p</i> = 0.02), but positively correlated with TCTP levels (0.252, <i>p</i> = 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], <i>p</i> = 0.019). It did not differ by aspirin hypersensitivity or atopy status, or autologous serum skin test positivity. <b><i>Conclusion:</i></b> 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.