title: Differential astrocyte response to Theiler's murine encephalomyelitis virus infection.
abstract: OBJECTIVE
  We aimed to address if selective astrocyte apoptosis is involved in the lack of murine demyelinating disease following infection by the L*-1 variant of Theiler's virus. In addition, we investigated whether L*-1-infected astrocytes were able to selectively express molecules whose effects would play a role as pathogenic factors.
  
  
  METHODS
  Murine cultured astrocytes were infected with two Theiler viruses, the DA strain and the mutated DA variant L*-1, which does not synthesize the out of frame L* protein.
  
  
  RESULTS
  Neither DA nor L*-1 provoked apoptosis, although they replicated in astrocytes inducing GFAP and iNOS expression, as well as subsequent nitric oxide production. In addition, both viruses caused an enhanced expression of ICAM-1, VCAM-1 and decay accelerating factor (DAF). In this connection, values of VCAM-1 and DAF induced by L*-1 were higher and lower, respectively, than those induced by DA.
  
  
  CONCLUSIONS
  Since no apoptosis was found, such mechanism would not be involved in the lack of TMEV-induced demyelinating disease by L*-1. In contrast, selective expression of VCAM-1 and DAF molecules induced by L*-1 could have a role in virus clearance from the central nervous system.
authors.affiliation: Department of Thrombosis and Haemostasis, Hematological Research Institute, National Academy of Medicine, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Roberto G
authors.initials: RG
authors.lastname: Pozner
authors.forename: Maria I
authors.initials: MI
authors.lastname: Berría
authors.forename: Soledad
authors.initials: S
authors.lastname: Negrotto
authors.forename: Mirta
authors.initials: M
authors.lastname: Schattner
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Gómez
mesh_terms: D000818:Animals; D017209:Apoptosis; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology* / Q000821:virology*; D018958:CD55 Antigens / Q000032:analysis; D002478:Cells, Cultured; D004679:Encephalomyelitis / Q000453:epidemiology; D015870:Gene Expression; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D051379:Mice; D009569:Nitric Oxide / Q000032:analysis; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D017945:Theilovirus / Q000502:physiology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000032:analysis
chemical_list: D018958:CD55 Antigens; D005904:Glial Fibrillary Acidic Protein; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse