HVT-vectored ND-IBD vaccine
The present invention regards a new and Improved HVT-vectored ND-IBD vaccine, comprising a recombinant HVT comprising the VP2 gene from IBDV and the F gene from NDV to a target animal. The recombinant HVT can be used in a vaccine for poultry, which displayed good viral vector replication, effective expression of the NDV F- and IBDV VP2 genes, improved immunoprotection against ND and IBD, and improved genetic stability over prior art constructs.
1. A recombinant DNA expression cassette comprising in the 5′ to 3′ direction and in the following order:
a. a murine cytomegalovirus immediate early 1 gene (mCMV-IE1) promoter,
b. an infectious bursal disease virus (IBDV) viral protein 2 (VP2) gene,
c. a transcription terminator,
d. a human cytomegalovirus immediate early 1 gene (hCMV-IE1) promoter, and
e. a Newcastle disease virus (NDV) fusion (F) protein gene.
2. The recombinant DNA expression cassette of claim 1 , wherein one or more or all of the conditions apply selected from the group consisting of: the mCMV-IE1 gene promoter is a complete promoter; the IBDV VP2 gene encodes a VP2 protein from a classic type IBDV; the transcription terminator comprises both a terminator region and a polyA region; the transcription terminator is derived from simian virus 40 (SV40); the hCMV-IE1 gene promoter is a core promoter; the NDV F gene is from a lentogenic NDV strain; the expression cassette comprises an additional transcription terminator which is located downstream of the NDV F gene; and the additional transcription terminator is derived from the hCMV-IE1 gene.
3. A recombinant DNA molecule comprising the recombinant DNA expression cassette of claim 1 .
4. A recombinant herpes virus of turkeys virus (HVT), comprising the recombinant DNA expression cassette of claim 1 , wherein the expression cassette is inserted in the Us region of the genome of the recombinant HVT.
5. A host cell comprising the recombinant HVT of claim 4 .
6. A vaccine for poultry comprising the recombinant HVT of claim 4 , and a pharmaceutically acceptable carrier.
7. The vaccine of claim 6 , comprising at least one additional immunoactive component.
8. A vaccine for poultry comprising the host cell of claim 5 and a pharmaceutically acceptable carrier.
9. The vaccine of claim 8 , comprising at least one additional immunoactive component.
10. A recombinant herpes virus of turkeys virus (HVT), comprising the recombinant DNA expression cassette of claim 2 , wherein the expression cassette is inserted in the Us region of the genome of the recombinant HVT.
11. A host cell comprising the recombinant HVT of claim 10 .
12. A vaccine for poultry comprising the host cell of claim 11 and a pharmaceutically acceptable carrier.
13. A method of constructing the recombinant HVT of claim 4 , said method comprising the insertion of the recombinant DNA expression cassette into the Us region of the genome of the recombinant HVT.
14. A method of preparing the vaccine of claim 6 , said method comprising the steps of:
infecting host cells with the recombinant HVT,
harvesting the infected host cells, and
admixing the harvested infected host cells with a pharmaceutically acceptable carrier.
15. A method for preventing or reducing infection by IBDV, NDV, or IBDV and NDV, or associated signs of disease, the method comprising the administration of the vaccine of claim 6 to poultry.
16. A method of vaccinating poultry, comprising the step of inoculating poultry with the vaccine of claim 6 .
17. A method of vaccinating poultry, comprising the step of inoculating poultry with the vaccine of claim 7 .
18. A method for preventing or reducing infection by IBDV, NDV, or IBDV and NDV, or associated signs of disease in poultry, the method comprising the administration of the vaccine of claim 7 to poultry.