Abstract: Described is a replication-competent virus capable of replication and having lytic capacity in target cells. The virus comprises in the genome thereof, at least one DNA sequence coding for a silencing factor functional in reducing expression of a target gene in the target cells, operably linked to one or more expression control sequences, functional in the target cells. The use thereof in the preparation of a medicament and the use thereof in a method for lysing target cells expressing a virus inhibitory factor are also described.

Abstract: A method for producing viral gene delivery vehicles which can be transferred to pre-selected cell types by using targeting conjugates. The gene delivery vehicles comprise: 1) the gene of interest; and 2) a viral capsid or envelope carrying a member of a specific binding pair, the counterpart of which is not directly associated with the surface of the target cell. These vehicles can be rendered unable to bind to their natural cell receptor. The targeting conjugates include the counterpart member of the specific binding pair, linked to a targeting moiety which is a cell-type specific ligand (or fragments thereof). The number of the specific binding pair present on the viral vehicles can be, for example, an immunoglobulin binding moiety (e.g., capable of binding to a Fc fragment, protein A, protein G, FcR or an anti-Ig antibody), or biotin, avidin or streptavidin. The virus' outer membrane or capsid may contain a substance which mediates entrance of the gene delivery vehicle into the target cell.

Abstract: Described is a replication competent recombinant virus, being capable to replicate and having lytic capacity in target cells, the said cell being hampered in the p53 dependent apoptosis pathway, the virus including in the genome thereof, the coding sequence of at least one restoring factor functional in restoring the p53 apoptosis pathway in the said target cells, operably linked to one or more expression control sequences, functional in the said target cells, as well as the use thereof in the preparation of a medicament, in particular for suppressing uncontrolled cell growth.