Factors affecting cell fusion induced by Sendai virus.

Cell fusion mediated by exogenous Sendai virus appears to occur in four temperature-dependent stages. The first two, which include viral adsorption, are pH dependent and can be inhibited by viral antibody. Viral envelope constituents remain detectable on the cell surface during the third stage and disappear only when cell-to-cell fusion supervenes. The relationship of these interactions to possible mechanisms of cell fusion are discussed.