The present invention provides a modified paramyxovirus containing a reduced amount of
receptor-
binding protein compared with the
wild type; a method of preparing a modified paramyxovirus, comprising the following steps: (1) a step for introducing a
nucleic acid that suppresses the expression of a
receptor-
binding protein of a paramyxovirus into an animal
cell, (2) a step for infecting the paramyxovirus to the
cell, and (3) a step for isolating paramyxovirus particles replicated in the
cell; and a modified paramyxovirus prepared by the method of preparation mentioned above.The present invention also provides a
chimera protein wherein a
fusion protein of a
virus has been joined or bound to
a peptide that binds specifically to a cell
surface marker; a
nucleic acid that encodes the
chimera protein; an animal cell capable of expressing the
chimera protein on the cell surface thereof; a modified paramyxovirus expressing the chimera
protein on the
virus particle surface thereof; and a method of preparing a
tissue targeting paramyxovirus, comprising: (1) a step for supplying a
nucleic acid that encodes a chimera
protein wherein a
fusion protein of a
virus has been joined or bound to
a peptide that binds specifically to a cell
surface marker of the target cells, (2) a step for introducing the nucleic acid supplied in (1) into an animal cell in an expressible state, and expressing the same, (3) a step for infecting a paramyxovirus to the cell, and (4) a step for isolating paramyxovirus particles replicated in the cell.