 Moreover, the oncolytic potential of paramyxovirus can be enhanced by mutations in the fusion (F) gene protease-cleavage site, which allows the F-protein to be more efficiently processed by cellular proteases.The introduction of the F gene of SeV in the form of a plasmid into the tumor tissue in mice by electroporation showed that the expression of the F gene increases the T cell infiltration of the tumor with CD4 + and CD8 + cells and inhibits tumor growth.It was also shown in other similar experiments that cancer cells themselves, transfected with plasmids that encode viral membrane glycoproteins with fusion function, cause the collective death of neighboring cells forming syncytium with them.