Adenoviral expression vectors

Abstract

The present invention provides a recombinant adenovirus vector characterized by the partial or total deletion of adenoviral E2B function and having an expression cassette containing a heterologous sequence encoding a protein of interest inserted into the E1 region. Such vectors are designed to reduce or eliminate the occurrence of replication competent adenovirus contamination. Additionally, the expression cassette of the vector may contain one or more regulatory elements capable of increasing the expression of the heterologous sequence and/or reducing the expression of viral proteins. Such a reduction in expression of viral proteins reduces the cytotoxicty and immunogenicity of the adenovirus vectors when administered in vivo. Transformed production host cells and a method of producing recombinant proteins and gene therapy also are included within the scope of this invention.

1 . A recombinant adenoviral vector comprising 
 (a) an expression cassette inserted in to the E1 region of the adenoviral vector, wherein said expression cassette comprises 
 (i) a regulatory element operably linked to a first nucleic acid molecule comprising a nucleotide sequence encoding protein of interest; and  
 (ii) one or more elements selected from the group consisting of an insulator sequence, a polyA signal sequence that is substituted for the E1B polyA signal sequence; and a posttranscriptional regulatory element; and  
   (b) a mutation that deletes or inactivates the activity of the E2B polymerase.    
     
     
         2 . The vector of  claim 1 , wherein the expression cassette further comprises one or more elements selected from a CMV promoter, a tripartite leader sequence, a WPRE sequences a CTCF binding site.  
     
     
         3 . The vector of  claim 1 , wherein the nucleic acid sequence encodes an interferon.  
     
     
         4 . The vector of  claim 3 , wherein the interferon is interferon alpha 2b.  
     
     
         5 . The vector of  claim 1 , wherein the expression cassette is the expression cassette shown in  FIG. 5 .  
     
     
         6 . The vector of  claim 1 , wherein the vector comprises the sequence shown in  FIG. 6 .  
     
     
         7 . The vector of  claim 1  derived from a human adenovirus serotype 5.  
     
     
         8 . The vector of  claim 7 , comprising a deletion beginning at nucleotide 357 and ending at nucleotide 4030 or 4050, a deletion beginning at nucleotide 28,597 and ending at nucleotide 30,471 and a deletion beginning at 28,597 and ending at nucleotide 30,471.  
     
     
         9 . A method for treating cancer comprising administering the vector of  claim 1  to a subject in need of such treatment.  
     
     
         10 . The method of  claim 9 , wherein the cancer is bladder cancer.  
     
     
         11 . The method of  claim 9 , wherein the vector is administered in the range of between about 1×10 8  particles/ml to about 1×10 12  particles/ml.  
     
     
         12 . The method of  claim 11 , wherein the vector is administered in the range of between about 1×10 9  particles/ml to about 1×10 11  particles/ml.  
     
     
         13 . The method of  claim 9 , wherein the vector is administered in conjunction with an enhancing agent.  
     
     
         14 . The method of  claim 13 , wherein the enhancing agent is SYN-3.