Influence of dextran sulfate on the fusion of Sendai virus with liposomes.

Liposomes made from phosphatidylserine and labeled with the fluorescence probe pyrene-phosphatidylcholine were used for studies of the influence of dextran sulfate on the fusion process. The fusion is monitored by the increase of the fluorescence signal due to the dilution of the fluorescence probes as a result of the fusion of liposomes with the virus. Addition of dextran sulfate inhibits the fusion process. Binding of the sulfate groups of the polymer to aminogroups on the virus proteins is considered as the reason for the inhibiting effect of this polymer on fusion.