Echovirus type 19 and herpes simplex type 2 infection in human placenta tissue explants

1. Light and electron microscopy have been used to characterize echovirus 19 and herpes simplex type 2 infection of human placenta tissue in vitro. Immunofluorescence, autoradiography and virus adsorption were used to determine virus replication in this system. 2. Placental tissue was permissive to echovirus 19. Trophoblast cells were lysed with liberation of mature virions. However, during the 48-h period of observation, few cells were damaged and the trophoblastic structure was maintained. 3. HSV-2 infection in placental tissue was aborted although trophoblastic cells allowed virus adsorption, penetration and uncoating. A characteristic cytopathic effect was observed in infected trophoblastic cells in spite of the abortive infection