Abstract: Zeng Yueping, Zhu Chenyu, Chen Cheng, Jia Qiannan, Jin Hongzhong Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Center for Translational Medicine, Beijing 100730, China Corresponding author: Jin Hongzhong, Email: jinhongzhong@263.net 【Abstract】 Objective To evaluate the effect of microRNA-143 （miR-143） on interleukin （IL）-13-induced of kallikrein 7（KLK7） in primary normal human epidermal keratinocytes（NHEKs）. Methods Some NHEKs at exponential growth phase were divided into 4 groups to be treated with recombinant human IL-13 at different concentrations of 0, 2, 10 and 50 μg/L respectively for 24 hours, and some NHEKs were treated with 50 μg/L IL-13 for 0, 6, 12, 24 and 48 hours separately. After the treatment, NHEKs were collected, and total RNA was extracted. Real-time fluorescence-based quantitative PCR was performed to determine the mRNA of KLK7. Some other NHEKs were divided into another 4 groups: NHEK group （blank control group） receiving no treatment, IL-13 group treated with 50 μg/L IL-13, miR-NC group transfected with miRNA mimics negative control followed by the treatment with 50 μg/L IL-13, and miR-143 group transfected with miR-143 mimics followed by the treatment with 50 μg/L IL-13. After 24-hour treatment with IL-13, real-time fluorescence-based quantitative PCR and Western blot analysis were conducted to determine the mRNA and protein of KLK7 respectively in the above groups. Results After 24-hour treatment with IL-13 at concentrations of 0, 2, 10 and 50 μg/L, the mRNA of KLK7 in NHEKs was 1.00 ± 0.12, 0.89 ± 0.04, 1.15 ± 0.09 and 1.70 ± 0.10 respectively, and significantly increased along with the increase of IL-13 concentrations （F = 92.48, P < 0.05）. After 0-, 6-, 12-, 24- and 48-hour treatment with 50 μg/L IL-13, the mRNA of KLK7 in NHEKs was 1.00 ± 0.05, 1.05 ± 0.12, 1.71 ± 0.20, 1.97 ± 0.19 and 2.48 ± 0.13 respectively, and significantly increased over time （F = 206.44, P < 0.05）. Compared with the miR-NC group, the miR-143 group showed significantly decreased mRNA and protein of KLK7 （t = 6.76, 4.23 respectively, both P < 0.05）. Conclusion In NHEKs, IL-13 can up-regulate the of KLK7, likely by the regulation of miR-143.

Key words: Dermatitis, atopic, Keratinocytes, Interleukin-13, Kallikrein 7, MicroRNA-143