Wet-wrap treatment using dilutions of tacrolimus ointment and fluticasone propionate cream in human APOC1 (+/+) mice with atopic dermatitis
Background: Wet-wrap treatment (WWT) with diluted topical steroids is widely used in atopic dermatitis (AD). Mice with transgenic overexpression of human apolipoprotein C1 (APOC1) in the liver and the skin are not only characterized by hyperlipidaemia and raised IgE levels, but also by pruritic dermatitis and a disturbed skin barrier function, providing a novel in vivo mouse model for AD. Objectives: We investigated an adapted WWT method in the AD model in APOC1 mice in order to establish its efficacy. Methods: The effect of topical 0.1% and 0.03% tacrolimus ointment, tacrolimus base ointment, different dilutions of 0.05% fluticasone propionate (FP) cream and emollient on the development of dermatitis in APOC1 mice was investigated. WWT was performed with 0.03% tacrolimus ointment or 0.017% FP cream. Results: AD in APOC1 mice responded to topical treatment with tacrolimus or FP. In contrast to tacrolimus treatment, FP treatment was associated with loss of body weight. WWT reinforced several therapeutic aspects, notably improvements in transepidermal water loss and in epidermal thickness. WWT using tacrolimus 0.03% ointment was more effective than WWT using FP 0.017% cream. Conclusions: AD in APOC1 mice responds to treatment with (diluted) tacrolimus or FP; treatment with FP cream, but not tacrolimus ointment, was associated with weight loss. In this study, the adapted WWT using tacrolimus or FP in mice had a limited improving effect as compared with open application of tacrolimus or FP.