Replication-defective arenavirus vectors
The invention relates to an infectious arenavirus particle that is engineered to contain a genome with the ability to amplify and express its genetic information in infected cells but unable to produce further infectious progeny particles in normal, not genetically engineered cells. One or more of the four arenavirus open reading frames glycoprotein (GP), nucleoprotein (NP), matrix protein Z and RNA-dependent RNA polymerase L are removed or mutated to prevent replication in normal cells but still allowing gene expression in arenavirus vector-infected cells, and foreign genes coding for an antigen or other protein of interest or nucleic acids modulating host gene expression are expressed under control of the arenavirus promoters, internal ribosome entry sites or under control of regulatory elements that can be read by the viral RNA-dependent RNA polymerase, cellular RNA polymerase I, RNA polymerase II or RNA polymerase III. The modified arenaviruses are useful as vaccines and therapeutic agents for a variety of diseases.
1. An infectious arenavirus particle comprising a genome wherein
i) one or more of the four arenavirus open reading frames coding for the glycoprotein (GP), nucleoprotein (NP), matrix protein Z and RNA-dependent RNA polymerase L are removed or mutated such that the infectious arenavirus particle is unable to produce further infectious progeny particles in normal, not genetically engineered cells but still allowing gene expression in arenavirus vector-infected cells; and
ii) the genome comprises a foreign ribonucleic acid coding for one or more tumor antigens.
2. The arenavirus particle according to claim 1 wherein the arenavirus open reading frame coding for glycoprotein (GP) is removed or mutated.
3. The arenavirus particle according to claim 1 wherein the genome comprises additional nucleic acids modulating host gene expression.
4. The arenavirus particle according to claim 1 wherein the arenavirus is lymphocytic choriomeningitis virus (LCMV).
5. A pharmaceutical preparation comprising an arenavirus particle according to claim 1 .
6. The arenavirus particle according to claim 1 , wherein an internal ribosome entry site is introduced into the viral genome.
7. The infectious arenavirus particle of claim 1 or claim 2 , wherein the open reading frames for the NP protein and the RNA-dependent RNA polymerase L of the arenavirus are intact.
8. The arenavirus particle according to claim 1 , wherein the foreign ribonucleic acid is expressed under control of one or more of the four arenavirus promoters 5′ UTR and 3′ UTR of the S segment, and 5′ UTR and 3′ UTR of the L segment, and/or under control of regulatory elements that can be read by the viral RNA-dependent RNA polymerase, cellular RNA polymerase I, RNA polymerase II or RNA polymerase III, expressed either by themselves or as read-through by fusion to arenavirus protein open reading frames.
9. The arenavirus particle according to claim 1 , wherein the tumor antigen is HER2/neu (breast cancer), GD2 (neuroblastoma), EGF-R (malignant glioblastoma), CEA (medullary thyroid cancer), CD52 (leukemia), MUC1 (expressed in hematological malignancies), gp100 protein, MELAN-A/MART1, or the product of the tumor suppressor gene WT1.
10. The arenavirus particle according to claim 1 , wherein the genome is engineered to have the ability to amplify and express its genetic information in the arenavirus vector infected cells.
11. A method of expressing a tumor antigen in a cell culture wherein the cell culture is infected with an arenavirus particle according to claim 1 .