Adenoviral vectors

1. An adenoviral vector comprising a repressible Major Late Promoter (MLP) and a plurality of adenoviral late genes, wherein the MLP comprises one or more repressor elements which are capable of regulating or controlling transcription of the adenoviral late genes, and wherein the nucleotide sequence of the MLP consists of the nucleotide sequence set forth in SEQ ID NO: 6 or 7.

2. The adenoviral vector as claimed in claim 1 , additionally comprising a plurality of adenoviral early genes and a transgene.

3. The adenoviral vector as claimed in claim 2 , wherein the transgene comprises a Tripartite Leader (TPL) in its 5′-UTR.

4. The adenoviral vector as claimed in claim 2 , wherein the transgene encodes a therapeutic polypeptide.

5. The adenoviral vector as claimed in claim 2 , wherein the transgene encodes a virus protein, or a protein that is capable of assembly in or outside of a cell to produce a virus-like particle.

6. The adenoviral vector as claimed in 5 , wherein the transgene encodes Norovirus VP1 or Hepatitis B HBSAG.

7. The adenoviral vector as claimed in claim 2 , wherein the transgene encodes an AAV Rep polypeptide, an AAV Cap polypeptide, an AAV Rep-Cap polypeptide and/or the transgene encodes an AAV genome.

8. A process for producing a transgene product, the process comprising the steps:

(a) infecting mammalian cells with an adenoviral vector as claimed in claim 2 ;

(b) culturing the infected mammalian cells in a culture medium under conditions such that a product of the transgene is expressed; and

(c) isolating or purifying the transgene product from the cells or from the cell culture medium.

9. The adenoviral vector as claimed in claim 1 , wherein a gene encoding a repressor protein which is capable of binding to the one or more repressor elements is encoded within the adenoviral vector.

10. The adenoviral vector as claimed in claim 9 , wherein the gene encoding the repressor protein is transcribed under the control of the MLP.

11. The adenoviral vector as claimed in claim 1 , wherein the adenoviral vector further encodes an adenovirus L4 100K protein and wherein the L4 100K protein is not under control of the MLP.

12. The adenoviral vector as claimed in claim 1 , wherein a transgene is inserted within an adenoviral early region, or within an adenoviral E1 region.

13. A composition comprising an adenovirus particle comprising an adenoviral vector as claimed in claim 1 , together with one or more physiologically-acceptable carriers, excipients or diluents.

14. A kit comprising an adenoviral vector as claimed in claim 1 , wherein the kit additionally comprises:

(i) a cell line that allows the adenoviral vector to infect the cells and replicate the adenoviruses' genome, wherein the cell line represses the adenoviral vector's MLP; and/or

(ii) one or more DNA plasmids for aiding in the construction of the adenoviral vector.

15. A mammalian cell comprising an adenoviral vector as claimed in claim 1 .

16. A process for producing a modified mammalian cell, the process comprising the step:

(a) infecting a mammalian cell with an adenoviral vector as claimed in claim 1 , whereby the mammalian cell then comprises the adenoviral vector.