title: The role of cell swelling and haemolysis in Sendai virus-induced cell fusion and in the diffusion of incorporated viral antigens.
abstract: The role of the haemolytic activity of Sendai virus in cell-cell fusion has been examined in monolayers of human erythrocytes and erythrocyte ghosts fused with either haemolytic or non-haemolytic virus. Morphological observations indicate that cell swelling and haemolysis is a distinct event in cell-cell fusion irrespective of whether it is virally induced or, in the case of non-haemolytic virus, experimentally induced. Osmotic swelling appears to be the driving force by which cells which have established sites of membrane fusion expand such sites to form poly-erythrocytes. Immunofluorescent labelling of viral antigens incorporated into the erythrocyte membrane as a result of viral envelope-cell fusion indicates that diffusion of antigens in the plane of the membrane is restricted in intact erythrocytes and resealed erythrocyte ghosts but not in haemolysed erythrocytes or unsealed ghosts. A perturbation of the erythrocyte membrane resulting from osmotic lysis appears to form a prerequisite for the lateral diffusion of viral elements.
mesh_terms: D000956:Antigens, Viral; D002459:Cell Fusion; D004910:Erythrocyte Membrane / Q000648:ultrastructure; D004912:Erythrocytes / Q000648:ultrastructure*; D005614:Freeze Fracturing; D006461:Hemolysis; D006801:Humans; D066298:In Vitro Techniques; D008855:Microscopy, Electron, Scanning; D008858:Microscopy, Phase-Contrast; D010222:Parainfluenza Virus 1, Human / Q000276:immunology
chemical_list: D000956:Antigens, Viral