Serum human β-defensin-1 (hBD-1) and -20G/A DEFB1 gene polymorphism in Behçet’s disease patients: Relation to clinical characteristics

Aim of the work:

Behçet’s disease (BD) is a multisystemic inflammatory disease of unknown cause. Beta defensins (β-defensins) are endogenous antimicrobial peptides that have the ability to kill or inactivate a wide spectrum of bacteria and fungi by changing their membranes stability. It also plays a significant role in inflammation owing to its chemotactic activity for T cells and immature dendritic cells. To explore whether β-defensins might be involved in BD pathogenesis, serum human β-defensin-1 (hBD-1) and defensin-β-1 (DEFB1)-20 G/A gene polymorphism were assessed in patients with BD.

Patients and methods

The study included 40 BD patients and 40 matched controls. Serum hBD-1 was assessed by enzyme-linked immunosorbent assay (ELISA) and the -20G/A genotypes (rs11362) were determined by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) analysis.

Results

The mean age of patients was 33.5 ± 10.8 years. They were 32 males and 8 females (M:F 4:1). Disease duration was 8.5 ± 7.3 years. In patients, the median serum hBD-1 concentration was 295.5 pg/ml (27.6–1776.6 pg/ml) and was significantly higher than in the control (median 129.6 pg/ml; 23.7–986.3 pg/ml) (p < 0.001). Serum hBD-1 significantly correlated with C-reactive protein (r = 0.85, p = 0.001) and platelets (r = 0.4, p = 0.012). No significant difference was found between patients and control regarding genotyping of -20G/A DEFB1 (rs11362). Skin manifestations were significantly higher among patients with GA genotype 18/23 (78.2 %) than patients with AA genotype 7/16 (43.8 %)(p = 0.027). However, there was no association between serum hBD-1 and −20A/G polymorphism.

Conclusions

The hBD-1 is implicated in the pathogenesis of BD and may be a possible therapeutic target.