title: Interleukin-13 Inhibits Lipopolysaccharide-Induced BPIFA1 Expression in Nasal Epithelial Cells.
abstract: Short palate, lung, and nasal epithelium clone 1 (SPLUNC1) protein is expressed in human nasopharyngeal and respiratory epithelium and has demonstrated antimicrobial activity. SPLUNC1 is now referred to as bactericidal/permeability-increasing fold containing family A, member 1 (BPIFA1). Reduced BPIFA1 expression is associated with bacterial colonization in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). Interleukin 13 (IL-13), predominately secreted by T helper 2 (TH2) cells, has been found to contribute to airway allergies and suppress BPIFA1 expression in nasal epithelial cells. However, the molecular mechanism of IL-13 perturbation of bacterial infection and BPIFA1 expression in host airways remains unclear. In this study, we found that lipopolysaccharide (LPS)-induced BPIFA1 expression in nasal epithelial cells was mediated through the JNK/c-Jun signaling pathway and AP-1 activation. We further demonstrated that IL-13 downregulated the LPS-induced activation of phosphorylated JNK and c-Jun, followed by attenuation of BPIFA1 expression. Moreover, the immunohistochemical analysis showed that IL-13 prominently suppressed BPIFA1 expression in eosinophilic CRSwNP patients with bacterial infection. Taken together, these results suggest that IL-13 plays a critical role in attenuation of bacteria-induced BPIFA1 expression that may result in eosinophilic CRSwNP.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, China Medical University and Hospital, Taichung, Taiwan.|Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Yung-An
authors.initials: YA
authors.lastname: Tsou
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, China Medical University and Hospital, Taichung, Taiwan.|Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Chia-Der
authors.initials: CD
authors.lastname: Lin
authors.affiliation: Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Hui-Chen
authors.initials: HC
authors.lastname: Chen
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, China Medical University and Hospital, Taichung, Taiwan.|Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Hui-Ying
authors.initials: HY
authors.lastname: Hsu
authors.affiliation: Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Lii-Tzu
authors.initials: LT
authors.lastname: Wu
authors.affiliation: Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chuan
authors.initials: C
authors.lastname: Chiang-Ni
authors.affiliation: Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan.|Division of Paediatric Infectious Diseases, Department of Paediatrics, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Chih-Jung
authors.initials: CJ
authors.lastname: Chen
authors.affiliation: Department of Applied Cosmetology, Hung Kuang University, Taichung, Taiwan.
authors.forename: Tsu-Fang
authors.initials: TF
authors.lastname: Wu
authors.affiliation: Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Min-Chuan
authors.initials: MC
authors.lastname: Kao
authors.affiliation: Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Yu-An
authors.initials: YA
authors.lastname: Chen
authors.affiliation: Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Ming-Te
authors.initials: MT
authors.lastname: Peng
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, China Medical University and Hospital, Taichung, Taiwan.
authors.forename: Ming-Hsui
authors.initials: MH
authors.lastname: Tsai
authors.affiliation: Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Chuan-Mu
authors.initials: CM
authors.lastname: Chen
authors.affiliation: Graduate Institute of Basic Medical Science, School of Medicine, China Medical University and Hospital, Taichung, Taiwan.|Department of Microbiology and Immunology, Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan.|Department of Nursing, Asia University, Taichung, Taiwan.
authors.forename: Chih-Ho
authors.initials: CH
authors.lastname: Lai
mesh_terms: D001419:Bacteria / Q000302:isolation & purification; D045744:Cell Line, Tumor; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D018793:Interleukin-13 / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D009297:Nasal Mucosa / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology; D010750:Phosphoproteins / Q000235:genetics*; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D015854:Up-Regulation
chemical_list: C485599:BPIFA1 protein, human; D006023:Glycoproteins; D018793:Interleukin-13; D008070:Lipopolysaccharides; D010750:Phosphoproteins; D016755:Proto-Oncogene Proteins c-jun; D048670:MAP Kinase Kinase 4