title: Effects of human parvovirus B19 VP1 unique region protein on macrophage responses.
abstract: BACKGROUND
  Activity of secreted phospholipase A (sPLA2) has been implicated in a wide range of cellular responses. However, little is known about the function of human parvovirus B19-VP1 unique region (VP1u) with sPLA2 activity on macrophage.
  
  
  METHODS
  To investigate the roles of B19-VP1u in response to macrophage, phospholipase A2 activity, cell migration assay, phagocytosis activity, metalloproteinase assay, RT-PCR and immunoblotting were performed.
  
  
  RESULTS
  In the present study, we report that migration, phagocytosis, IL-6, IL-1beta mRNA, and MMP9 activity are significantly increased in RAW264.7 cells by B19-VP1u protein with sPLA2 activity, but not by B19-VP1uD175A protein that is mutated and lacks sPLA2 activity. Additionally, significant increases of phosphorylated ERK1/2 and JNK proteins were detected in macrophages that were treated with B19-VP1u protein, but not when they were treated with B19-VP1uD175A protein.
  
  
  CONCLUSIONS
  Taken together, our experimental results suggest that B19-VP1u with sPLA2 activity affects production of IL-6, IL-1beta mRNA, and MMP9 activity, possibly through the involvement of ERK1/2 and JNK signaling pathways. These findings could provide clues in understanding the role of B19-VP1u and its sPLA2 enzymatic activity in B19 infection and B19-related diseases.
authors.affiliation: Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan. bstzang@csmu.edu.tw
authors.forename: Bor-Show
authors.initials: BS
authors.lastname: Tzang
authors.forename: Chun-Ching
authors.initials: CC
authors.lastname: Chiu
authors.forename: Chun-Chou
authors.initials: CC
authors.lastname: Tsai
authors.forename: Yi-Ju
authors.initials: YJ
authors.lastname: Lee
authors.forename: I-Jung
authors.initials: IJ
authors.lastname: Lu
authors.forename: Jing-Yu
authors.initials: JY
authors.lastname: Shi
authors.forename: Tsai-Ching
authors.initials: TC
authors.lastname: Hsu
mesh_terms: D000818:Animals; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000502:physiology*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D016732:Parvovirus B19, Human / Q000201:enzymology* / Q000235:genetics / Q000276:immunology*; D010587:Phagocytosis / Q000502:physiology; D010741:Phospholipases A / Q000235:genetics / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D053583:Interleukin-1beta; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D010741:Phospholipases A; D020780:Matrix Metalloproteinase 9