title: Interleukin 29 enhances expression of Toll receptor 3 and mediates antiviral signals in human keratinocytes.
abstract: OBJECTIVE
  Interleukin 29 (IL-29) is a class II cytokine and displays numerous immune functions other than its anti-viral and antiproliferation activities. This study is focused on the effect of IL-29 on human keratinocytes (KCs).
  
  
  METHODS
  Primary KCs were stimulated by various concentrations of IL-29 for different time periods, and antiviral proteins and TLR3 gene expression were then analyzed by real-time PCR. The signal pathways activated by IL-29 in KCs were detected by western blot. The antiviral activity of IL-29 was determined by methylthiazolyldiphenyl-tetrazolium bromide, and small interfering RNA knockdown was used to analyze the role of toll receptor 3 (TLR3) in the antiviral activity of IL-29.
  
  
  RESULTS
  IL-29 was able to induce expression of antiviral proteins and TLR3 gene expression in KCs. IL-29 pretreatment strongly enhanced herpes simplex virus type 1 (HSV-1)-induced expression of the interferon β (IFN-β) gene and protected the KCs from HSV-1 challenge. The IL-29 antiviral activity was partially dependent on TLR3 expression induced by this cytokine, and mechanistic studies demonstrated that the regulation of TLR3 expression by IL-29 might be partially dependent on Janus kinase /signal transducer and activator of transcription (JAK-STATs) activation.
  
  
  CONCLUSIONS
  IL-29-induced TLR3 expression is involved in antiviral activity of IL-29 in KCs, which suggests a feasible method to cure certain viral infections of the skin.
authors.affiliation: Institute of Dermatology, Department of Dermatology, 1st Affiliated Hospital, Anhui Medical University, 69 Meishan Road, Hefei, 230032, Anhui, China.
authors.forename: Sheng-Quan
authors.initials: SQ
authors.lastname: Zhang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xin
authors.initials: X
authors.lastname: Luo
authors.forename: Sen
authors.initials: S
authors.lastname: Yang
authors.forename: Yu
authors.initials: Y
authors.lastname: Chai
authors.forename: Hai-Liang
authors.initials: HL
authors.lastname: Huang
authors.forename: Xian-Yong
authors.initials: XY
authors.lastname: Yin
authors.forename: Dao-Jun
authors.initials: DJ
authors.lastname: Hu
authors.forename: Chun-Jun
authors.initials: CJ
authors.lastname: Yang
authors.forename: Jun-Lin
authors.initials: JL
authors.lastname: Liu
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Zhang
mesh_terms: D000998:Antiviral Agents / Q000378:metabolism; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation; D006561:Herpes Simplex / Q000276:immunology; D018259:Herpesvirus 1, Human / Q000378:metabolism; D006801:Humans; D016899:Interferon-beta / Q000378:metabolism; D007372:Interferons; D007378:Interleukins / Q000378:metabolism*; D015603:Keratinocytes / Q000378:metabolism* / Q000821:virology; D010766:Phosphorylation; D012313:RNA / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D050791:STAT Transcription Factors / Q000378:metabolism; D015398:Signal Transduction; D012867:Skin / Q000821:virology*; D051196:Toll-Like Receptor 3 / Q000378:metabolism*; D000095022:Interferon Lambda
chemical_list: D000998:Antiviral Agents; D016899:Interferon-beta; D007372:Interferons; D007378:Interleukins; D012313:RNA; D034741:RNA, Small Interfering; D050791:STAT Transcription Factors; D051196:Toll-Like Receptor 3; C000624353:interferon-lambda, human; D000095022:Interferon Lambda; C495344:TLR3 protein, human