Immunization agents and methods of use

1. A method of immunization of a mammalian subject comprising (a) administering to an inoculation site region in the body of the mammalian subject a composition comprising an effective amount of a replication-competent controlled herpesvirus which is a recombinant virus in which one or more replication-essential genes have been placed under the control of a gene switch that is inserted in the genome of the recombinant virus and that can be activated deliberately, and (b) exposing the inoculation site region in the body of the mammalian subject to a localized activation treatment that activates the recombinant virus to undergo a round of replication in the inoculation site region wherein the replication-competent controlled herpesvirus comprises a gene encoding an influenza virus antigen.

2. The method for immunization according to claim 1 , wherein the replication-competent controlled herpesvirus is a recombinant herpesvirus that comprises an inserted gene encoding a small-molecule regulator-activated transactivator which gene is functionally linked to a nucleic acid sequence that acts as a heat shock promoter as well as a transactivator-responsive promoter, and one or more transactivator-responsive promoters that are functionally linked to the one or more replication-essential genes.

3. The method for immunization according to claim 2 , wherein the replication-competent controlled herpesvirus further comprises at least one gene from another pathogen, a heterologous gene encoding an immune-modulatory polypeptide and a heterologous gene encoding another polypeptide.

4. The method of immunization according to claim 1 , wherein the replication-competent controlled herpesvirus is a recombinant virus selected from the group consisting of an HSV-1, an HSV-2, a varicella zoster virus, a cytomegalovirus and a roseola virus.

5. The method for immunization according to claim 2 , wherein the replication-competent controlled herpesvirus is a recombinant HSV-1 or HSV-2 and the replication-essential viral genes that are functionally linked to transactivator-responsive promoters include at least all copies of the ICP4 gene or the ICP8 gene.

6. The method for immunization according to claim 2 , wherein the small-molecule regulator-activated transactivator contains a ligand-binding domain from a progesterone receptor and is activated by a progesterone receptor antagonist or other molecule capable of interacting with the ligand-binding domain and activating the transactivator.

7. The method for immunization according to claim 2 , wherein the replication-competent controlled herpesvirus is a recombinant HSV-1 selected from the group consisting of HSV-GS1, HSV-GS3, HSV-GS4 and derivatives therefrom.

8. The method for immunization according to claim 2 , further comprising administering a second virus that has a host range that overlaps that of the replication-competent controlled herpesvirus, the second virus having a replication-essential gene functionally linked to a transactivator-responsive promoter.

9. The method for immunization according to claim 2 , further comprising a second virus that has a host range that overlaps that of the replication-competent controlled herpesvirus, wherein a replication-essential gene from the second virus is expressed under the control of a transactivator-responsive promoter by the replication-competent controlled herpesvirus and the second virus is defective in said replication-essential gene.

10. The method for immunization according to claim 2 , wherein the composition that is administered to the inoculation site region further comprises an effective amount of a small-molecule regulator that is capable of activating the transactivator.

11. The method for immunization according to claim 2 , wherein:

(a) the composition comprising an effective amount of the replication-competent controlled herpesvirus of claim 3 is administered to the inoculation site region, and

(b) the inoculation site region is exposed to an activating heat dose in the presence in the inoculation site region of an effective concentration of a small-molecule regulator that activates the transactivator of the replication-competent controlled herpesvirus.

12. The method for immunization according to claim 10 , wherein:

(a) the composition further comprising an effective amount of a small-molecule regulator is administered to the inoculation site region, and

(b) the inoculation site region is exposed to an activating heat dose.

13. The method for immunization according to claim 1 , wherein the replication-competent controlled herpesvirus is a recombinant herpesvirus that comprises an inserted gene encoding a transactivator activated by a small-molecule regulator, wherein the gene encoding the transactivator is functionally linked to a nucleic acid that acts as a heat shock promoter, and one or more transactivator-responsive promoters that are functionally linked to one or more replication-essential genes.

14. The method for immunization according to claim 13 , wherein the replication-competent controlled herpesvirus further comprises at least one gene from another pathogen, a heterologous gene encoding an immune-modulatory polypeptide and a heterologous gene encoding another polypeptide.

15. The method for immunization according to claim 1 , wherein the replication-competent controlled herpesvirus is a recombinant herpesvirus that comprises an inserted gene encoding a small-molecule regulator-activated transactivator wherein the gene encoding the transactivator is functionally linked to a nucleic acid that acts as a constitutively active promoter or a transactivator-responsive promoter, a first replication-essential gene of the replication-competent controlled herpesvirus is functionally linked to a promoter activated by heat and a second replication-essential gene of the replication-competent controlled herpesvirus is functionally linked to a transactivator-responsive promoter.

16. The method for immunization according to claim 15 , wherein the replication-competent controlled herpesvirus further comprises at least one gene from another pathogen, a heterologous gene encoding an immune-modulatory polypeptide and a heterologous gene encoding another polypeptide.

17. The method of immunization of claim 1 , wherein the effective amount of a replication-competent controlled virus is an amount of the replication-competent controlled virus that upon single or repeated administration to the subject followed by the activation treatment detectably enhances the subject's resistance to infection by the wild type virus from which the replication-competent controlled virus was derived and/or detectably reduces disease severity, disease duration or mortality subsequent to infection with said wild type virus and wherein a corresponding amount of a replication-defective comparison virus, administered in a similar composition and to a similar body region of a similar subject induces a lower level of such functional immunity.

18. The method of immunization of claim 1 , wherein said recombinant virus is replication-competent controlled herpesvirus comprising a gene encoding a small-molecule regulator-activated transactivator which gene is functionally linked to a nucleic acid sequence that acts as a heat shock promoter as well as a transactivator-responsive promoter, and one or more transactivator-responsive promoters that are functionally linked to at least all copies of the ICP4 gene or the ICP8 gene.

19. The method of immunization of claim 18 , wherein the small-molecule regulator-activated transactivator contains a ligand-binding domain from a progesterone receptor and is activated by a progesterone receptor antagonist or other molecule capable of interacting with the ligand-binding domain and activating the transactivator.

20. The method of immunization of claim 1 , wherein said replication-competent controlled herpesvirus is HSV-GS1 or HSV-GS3.