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Updated: May 11, 2026

Human Serum Anti-aquaporin-4 Immunoglobulin G Detection by Cell-based Assay
Published on: April 5, 2019
Normal immunostaining pattern for aquaporin-5 in the lesions of palmoplantar hyperhidrosis
Kyoko Nakahigashi1, Takashi Nomura, Yoshiki Miyachi
1Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Abstract:
Aquaporin-5 (AQP-5) is a water-transporting protein expressed in mammal sweat glands. It has been reported that the expression of AQP-5 is involved in sweating of mice, rats, and horses. However, the physiological function of human AQP-5 is still uncertain. In this report, we examined the expression pattern of AQP-5 in the skin lesions of palmoplantar hyperhidrosis in patients with Nagashima-type palmoplantar hyperkeratosis (PPK). We found that there was no significant difference in AQP-5 expression in the palmoplantar skin of healthy subjects and patients with palmoplantar hyperhidrosis. Our findings suggest that a mechanism other than AQP-5 may be involved in the pathogenesis of hyperhidrosis in PPK.
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