Electron microscopic study of penetration of newcastle disease virus into cells leading to formation of polykaryocytes

Abstract

Humanamnion (FL) or lung epithelial (Lu 106) cells grown in monolayers fuse into giant multinuclear cells within a few hours, when treated with Newcastle disease virus [NDV] at high input multiplicity. Cell monolayers grown on collodion films were treated with NDV and after periods of 2 min. to 3 hr. were prepared for electron microscopy. Ferritin labeled antibody was used to identify NDV. Within 2-10 min. of adsorption virions were demonstrable on the cell wall membranes, inside vacuoles, and also with viral envelope partly fused with cell wall membrane. In polykaryocytes induced by NDV in Lu 106 cells remnants of cell wall membranes showing numerous breaks may still be present after 3 hr.