Placental endothelial cells can be productively infected by Parvovirus B19.
BACKGROUND
Parvovirus B19 vertical transmission occurs in about 30% of cases of maternal infection and may result in foetal hydrops or intrauterine foetal death. Details on the mechanism of transplacental transmission of B19 virus and subsequent foetal infection have not been elucidated.


OBJECTIVE
To investigate the extent and distribution of B19 virus infection in placental tissues.


METHODS
Virological, histological, electron microscopy, immunohistochemical and immunofluorescence analysis of placental tissues obtained from a case of intrauterine foetal death caused by B19 virus.


RESULTS
Real-time PCR analysis showed B19 virus DNA in placental samples. Histology, immunohistochemistry and electron microscopy demonstrated the concomitant infection of both foetal erythroid precursors and placental endothelial cells. In situ hybridisation for B19 virus nucleic acids, immunohistochemistry for B19 virus proteins and double labelling immunofluorescence confirmed that endothelial cells were productively infected by B19 virus.


CONCLUSIONS
Foetal capillary endothelium in placental villi can be an additional target of productive B19 virus infection. Infection of placental endothelial cells may lead to a structural and functional damage critical both for altering maternal-foetal blood exchanges and for spreading the infection to the foetus, possibly concurring to the development of foetal hydrops and intrauterine foetal death.
Pasquinelli
Gianandrea
G
Division of Clinical Pathology, Department of Radiological and Histocytopathological Sciences, University of Bologna, Bologna, Italy.
Bonvicini
Francesca
F
Foroni
Laura
L
Salfi
Nunzio
N
Gallinella
Giorgio
G
D000328:Adult; D000818:Animals; D002478:Cells, Cultured; D004279:DNA, Viral / Q000302:isolation & purification; D042783:Endothelial Cells / Q000648:ultrastructure / Q000821:virology*; D015672:Erythroid Precursor Cells / Q000821:virology; D005260:Female; D006801:Humans; D010322:Parvoviridae Infections / Q000473:pathology* / Q000635:transmission*; D016732:Parvovirus B19, Human / Q000254:growth & development*; D010920:Placenta / Q000473:pathology / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy
D004279:DNA, Viral