Interleukin-8 content in the stratum corneum as an indicator of the severity of inflammation in the lesions of atopic dermatitis.

BACKGROUND

Atopic dermatitis (AD) is an inflammatory skin disease characterized by both acute and chronic eczema. Various markers are used to clinically evaluate the severity of AD. In order to identify a marker of local severity of AD, we measured IL-8, IL-18, vascular endothelial growth factor (VEGF), and transforming growth factor-α (TGF-α) levels in the stratum corneum (scIL-8, scIL-18, scVEGF and scTGF-α) and evaluated the correlation between the levels of these cytokines and the clinical severity scores of localized skin lesions.

METHODS

Stratum corneum samples were collected from the skin lesions of 50 patients with AD using the tape-stripping technique, and the scIL-8, scIL-18, scVEGF and scTGF-α levels were evaluated using the ELISA method. The trans-epidermal water loss and skin water content of the lesions were also measured prior to tape stripping.

RESULTS

The levels of scIL-8, scIL-18, scVEGF and scTGF-α were significantly higher in patients with AD than in healthy controls. Additionally, the levels of scIL-8, scIL-18 and scVEGF significantly correlated with the severity of AD.

CONCLUSIONS

Among these cytokines, scIL-8 showed the highest correlation with the severity scores of lesions in AD as well as other parameters. Our results also suggest that measuring cytokines in the stratum corneum by using ELISA combined with tape stripping is a convenient method to evaluate the severity of skin lesions in AD.