title: Antiviral activity of polysaccharide extract from Laminaria japonica against respiratory syncytial virus.
abstract: This study was designed to investigate the inhibition activity of polysaccharide extract from Laminaria japonica against RSV. The polysaccharide from Laminaria japonica was isolated by ethanol precipitation. HEK293 cells were infected with RVS, and the antiviral activity of polysaccharide extract against RSV in host cells was tested. By using ELISA and western blot assay, the expression level of IFN-α and IRF3 and their functional roles in polysaccharide-mediated antiviral activity against RSV were investigated. The polysaccharide extract from Laminaria japonica had low toxicity to HEK293 cell. The TC50 to HEK293 cells was up to 1.76mg/mL. Furthermore, the EC50 of polysaccharide extract to RSV was 5.27μg/mL, and TI was 334. The polysaccharide extract improved IRF-3 expression which promoted the level of IFN-α.
  
  
  CONCLUSIONS
  Polysaccharide extract from Laminaria japonica elicits antiviral activity against RSV by up-regulation of IRF3 signaling-mediated IFN-α production.
authors.affiliation: Clinical Laboratory, Liaocheng People's Hospital of Taishan Medical University, Shandong 252000, China; Shandong University School of Medicine, Shandong 250012, China.
authors.forename: Yin-Guang
authors.initials: YG
authors.lastname: Cao
authors.affiliation: Clinical Laboratory, Liaocheng People's Hospital of Taishan Medical University, Shandong 252000, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Hao
authors.affiliation: Clinical Laboratory, Liaocheng People's Hospital of Taishan Medical University, Shandong 252000, China; Shandong University School of Medicine, Shandong 250012, China. Electronic address: 13065081930@163.com.
authors.forename: Zhi-Hui
authors.initials: ZH
authors.lastname: Li
authors.affiliation: Clinical Laboratory, Liaocheng People's Hospital of Taishan Medical University, Shandong 252000, China.
authors.forename: Shun-Tao
authors.initials: ST
authors.lastname: Liu
authors.affiliation: School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia. Electronic address: lwang@csu.edu.au.
authors.forename: Le-Xin
authors.initials: LX
authors.lastname: Wang
mesh_terms: D000998:Antiviral Agents / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D015153:Blotting, Western; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D000431:Ethanol / Q000737:chemistry; D057809:HEK293 Cells; D054884:Host-Pathogen Interactions; D006801:Humans; D050838:Interferon Regulatory Factor-3 / Q000378:metabolism; D016898:Interferon-alpha / Q000378:metabolism; D007795:Laminaria / Q000737:chemistry; D008517:Phytotherapy; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D010946:Plants, Medicinal; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D012136:Respiratory Syncytial Viruses / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D015398:Signal Transduction / Q000187:drug effects; D012997:Solvents / Q000737:chemistry; D015854:Up-Regulation; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; C494232:IRF3 protein, human; D050838:Interferon Regulatory Factor-3; D016898:Interferon-alpha; D010936:Plant Extracts; D011134:Polysaccharides; D012997:Solvents; D000431:Ethanol
keywords: Antiviral activity; Interferon-alpha; Laminaria japonica; Polysaccharide extract; Respiratory syncytial virus