Attenuated microorganism strains and their uses

Abstract

This application relates to the use of attenuated prokaryotic microorganism strains (such as Salmonella) expressing nucleic acid encoding HPV proteins as vaccines against HPV infection and the associated increased risk of cancer. In particular, the work shows that it is possible to assemble VLPs in a prokaryotic organism and that nasal immunization of mice with the strains HPV-specific conformationally dependent and neutralizing antibodies in serum and genital secretions. The experiments described herein show that it is also possible to assemble chimeric VLPs of a HPV including a fusion partner and that tumour protection can be induced.

1 . An attenuated strain of a prokaryotic microorganism transformed with nucleic acid encoding papillomavirus virus major capsid protein wherein the protein assembles in the microorganism to form virus like particles (VLPs).  
     
     
         2 . The attenuated microorganism strain of  claim 1  which is an attenuated stain of Salmonella.  
     
     
         3 . The attenuated microorganism strain of  claim 2  wherein the Salmonella strain is  Salmonella typhimurium, Salmonella typhi, Salmonella dublin,  or  Salmonella enteretidis.    
     
     
         4 . The attentuated microorganism strain of  claim 1  which is an attenuated strain of  Escherichia coli,  Shigella, Yersinia, Lactobacillus. Mycobacteria or Listeria.  
     
     
         5 . The attenuated microorganism strain of  claim 1  wherein the nucleic acid encodes a human papillomavirus virus major capsid protein.  
     
     
         6 . The attenuated microorganism strain of  claim 1  wherein the HPV strain is HPV16, 18, 31, 45 or 56.  
     
     
         7 . The attenuated microorganism strain of  claim 1  wherein the papillomavirus virus major capsid protein is L1 protein.  
     
     
         8 . The attenuated microorganism strain of  claim 1  wherein the papillomavirus virus major capsid protein is expressed as a chimera with a fusion partner.  
     
     
         9 . The attenuated microorganism strain of  claim 8 , wherein the papillomavirus major capsid protein is coexpressed with L2 protein, the L2 protein being fused to the fusion partner.  
     
     
         10 . The attenuated microorganism strain of  claim 8  wherein the fusion partner is E6, E7 or E2 HPV protein, an immunogenic protein from a non-HPV pathogen or a tumour specific antigen.  
     
     
         11 . The attenuated microorganism strain of  claim 1  wherein the microorganism is transformed with nucleic acid encoding two or more papillomavirus virus major capsid proteins.  
     
     
         12 . A composition comprising one or more of the attenuated microorganisms of  claim 1 , in combination with a physiologically acceptable carrier.  
     
     
         13 . A vaccine comprising one or more of the attenuated microorganisms of claims  1 , in combination with a physiologically acceptable carrier.  
     
     
         14 . The vaccine of  claim 13  formulated for mucosal immunization.  
     
     
         15 . The vaccine of  claim 14  wherein the mucosla immunization is via oral, rectal, nasal, or genital routes.  
     
     
         16 . The vaccine of  claim 13  wherein the vaccine provides protection against papillomavirus infection or cancer of the anogenital tract.  
     
     
         17 . A method for producing assembled papillomavirus virus like particles comprising culturing an attenuated microorganism strain of  claim 1  and recovering the assembled virus like particles thus produced.  
     
     
         18 . A method of detecting the presence of anti-papillomavirus antibodies in a sample from a subject, the method comprising immobilizing the HPV VLPs on a solid support, exposing the support to the sample and detecting the antibodies binding to the immobilized HPV VLPs, wherein the HPV VLPs are produced by an attenuated microorganism stain of  claim 1 .  
     
     
         19 . A method of treating a patient in need of prophylaxis or therapy of a papillomavirus infection or papillomavirus associated cancer of the anogenital tract comprising administering to that patient a prophylactically or therapeutically effective amount of an attenuated microorganism as claimed in  claim 1.