Aquaporin 3 and E-Cadherin Expression in Perilesional Vitiligo Skin

To investigate the keratinocyte adhesion in perilesional vitiligo skin through the immunolocalization of Aquaporin-3 (AQP3) and E-cadherin. Setting and design: Sixty five subjects were selected. These included 40 cases with vitiligo and 25 age and gender-matched healthy subjects as a control group. Materials and

The following sequence of events can be suggested for vitiligo pathogenesis, based on findings in perilesional skin: AQP3 is downregulated by a primary unknown factor and this will lead to down regulation of its downstream molecules, mainly phosphatidylinositol 3-kinase, E-cadherin and catenins, which is followed by defective keratinocyte adhesion and decreased release of keratinocyte-derived growth factors. Subsequently a secondary event, physical trauma, oxidative stress or autoantibodies, may lead to exfoliation of keratinocytes and pigmented cells.

Skin biopsies were taken from perilesional skin of cases and from site-matched areas of control subjects. The expression of AQP3 and E-cadherin was evaluated by immunohistochemical techniques. Statistical analysis:

Regarding AQP3 expression, strong intensity, diffuse distribution, higher percent of expression and higher H-score (p<0.001 for all) were significantly associated with control skin compared with perilesional skin in follicular and inter-follicular epidermis. Regarding E-cadherin expression, moderate intensity, higher percent of expression and higher H- score (p<0.001 for all) were significantly associated with control skin compared with perilesional skin in follicular and inter-follicular epidermis. No significant association was found between E-cadherin and AQP3 H-scores or percent of expression and clinical data of selected cases. No significant correlation was detected between E-cadherin and AQP3 H-scores or percent of expression and age of cases, disease duration or Vitiligo Disease Activity (VIDA) score.