title: The susceptibility of pregnant mice to encephalomyocarditis (EMC) virus infection on different days of gestation.
abstract: Pregnant mice of the BALB/c CrSlc strain were experimentally infected with the D variant of encephalomyocarditis virus (EMC-D, 5 x 10(2) PFU/head) on three different gestational days (GD). Mice were intraperitoneally inoculated with EMC-D on 11, 13 and 15 GD and sacrificed 3 days post inoculation. There was no significant difference in the fetal mortality among all inoculation groups. Placenta showed higher virus titer than fetus and dam's serum in all inoculation groups, and the virus titer of the fetus was lowest in the 15GD group. Histopathological changes and signals of viral RNAs detected by in situ hybridization were observed almost restricted to the spongiotrophoblast layer of the placenta in all inoculation groups, and the signals were strongest in the 11GD group. In the fetus of the11GD group, signals of viral RNAs were also seen in myocardium and hepatocytes. Ultrastructurally, intracytoplasmic aggregations of virus-like particles in crystalline array were observed in trophoblast cells and giant cells in the spongiotrophoblast layer in all inoculation groups.
authors.affiliation: Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Nakayama
authors.forename: Weiping
authors.initials: W
authors.lastname: Su
authors.forename: Kei-Ichi
authors.initials: K
authors.lastname: Katayama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakayama
authors.forename: Kunio
authors.initials: K
authors.lastname: Doi
mesh_terms: D000818:Animals; D018188:Cardiovirus Infections / Q000097:blood / Q000473:pathology / Q000821:virology*; D004195:Disease Models, Animal; D004198:Disease Susceptibility / Q000821:virology; D004686:Encephalomyocarditis virus / Q000235:genetics*; D005260:Female; D005333:Fetus / Q000821:virology; D005865:Gestational Age; D006652:Histological Techniques; D017403:In Situ Hybridization; D051379:Mice; D008807:Mice, Inbred BALB C / Q000821:virology*; D010920:Placenta / Q000648:ultrastructure / Q000821:virology; D011247:Pregnancy; D011270:Pregnancy, Animal; D012367:RNA, Viral / Q000235:genetics
chemical_list: D012367:RNA, Viral