Chien-Hui Hong1, Chih-Hung Lee2, Hsin-Su Yu3, Shau-Ku Huang4. 1. Department of Dermatology, National Yang Ming University, Taipei, Taiwan; Department of Dermatology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan. 2. Department of Dermatology, Kaohsiung, Chang Gung Memorial Hospital, Kaohsiung, Taiwan; Department of Dermatology, Chang Gung University, Taoyuan, Taiwan. 3. Department of Dermatology, Kaohsiung Medical University, Kaohsiung, Taiwan; National Health Research Institute, Miao-Li, Taiwan. 4. National Health Research Institute, Miao-Li, Taiwan. Electronic address: skhuang@nhri.org.tw.
Abstract
BACKGROUND: Atopic dermatitis (AD) is a common disease with genetic and environmental interactions. We previously reported lifetime exposure to cigarette smoke is associated with adult-onset AD. Aryl hydrocarbon receptor (AhR) is important in regulating environmental exposure to xenobiotics, including benzopyrenes (BP), a major polycyclic aromatic hydrocarbon (PAH) present in cigarette smoke. However, how AhR regulates immune responses in sensitization phase of AD remained elusive. METHODS: We investigated how BP affects epicutaneous sensitization response through AhR axis. We compared AhR expression in skin from AD patients and healthy controls. We measured immune responses (Langerhans cell migration and T cell polarization in epicutaneous Ova sensitization in mice with or without AhR defect. RESULTS: We found AhR and ARNT (AhR nuclear translocator) are upregulated in AD skin. BP exposure increases Langerhans cell migration, and increases IL-5, IL-13, and IL-17 levels when lymph node cells were re-challenged with Ova. The increased cytokine levels were attenuated in AhR defected mice. AhR agonists (BP and ITE) decreased E-cadherin expression, while AhR antagonist (CH223191) increased it in human primary keratinocytes. CONCLUSIONS: These results suggested AhR interacts with BP to polarize T cell responses, along with Langerhans cell migration. This study revealed a regulatory mechanism how cigarette smoking affects atopic sensitization through the benzopyrene-AhR interaction.
BACKGROUND:Atopic dermatitis (AD) is a common disease with genetic and environmental interactions. We previously reported lifetime exposure to cigarette smoke is associated with adult-onset AD. Aryl hydrocarbon receptor (AhR) is important in regulating environmental exposure to xenobiotics, including benzopyrenes (BP), a major polycyclic aromatic hydrocarbon (PAH) present in cigarette smoke. However, how AhR regulates immune responses in sensitization phase of AD remained elusive. METHODS: We investigated how BP affects epicutaneous sensitization response through AhR axis. We compared AhR expression in skin from ADpatients and healthy controls. We measured immune responses (Langerhans cell migration and T cell polarization in epicutaneous Ova sensitization in mice with or without AhR defect. RESULTS: We found AhR and ARNT (AhR nuclear translocator) are upregulated in AD skin. BP exposure increases Langerhans cell migration, and increases IL-5, IL-13, and IL-17 levels when lymph node cells were re-challenged with Ova. The increased cytokine levels were attenuated in AhR defected mice. AhR agonists (BP and ITE) decreased E-cadherin expression, while AhR antagonist (CH223191) increased it in human primary keratinocytes. CONCLUSIONS: These results suggested AhR interacts with BP to polarize T cell responses, along with Langerhans cell migration. This study revealed a regulatory mechanism how cigarette smoking affects atopic sensitization through the benzopyrene-AhR interaction.
Authors: Agnieszka Strzelak; Aleksandra Ratajczak; Aleksander Adamiec; Wojciech Feleszko Journal: Int J Environ Res Public Health Date: 2018-05-21 Impact factor: 3.390