Modified viral particles with immunogenic properties and reduced lipid content useful for treating and preventing infectious diseases

Abstract

The present invention relates to a method for reducing the occurrence and severity of infectious diseases, especially infectious diseases in which lipid-containing infectious viral organisms are found in biological fluids, such as blood. The present invention employs solvents useful for extracting lipids from the lipid-containing infectious viral organism thereby creating modified viral particles with reduced infectivity and enhanced antigenicity. The present invention provides vaccine compositions, comprising these modified viral particles with reduced infectivity and enhanced antigenicity, optionally combined with a pharmaceutically acceptable carrier or an immunostimulant. The vaccine composition is administered to a patient to provide protection against the lipid-containing infectious viral organism. The vaccine compositions of the present invention include combination vaccines of modified viral particles obtained from one or more strains of a virus and/or one or more types of virus.

1 . A modified viral particle comprising at least a partially delipidated viral particle, wherein the partially delipidated viral particle:
 initiates a positive immune response in an animal or human patient; and,   incites protection against a virus,   
       wherein the modified viral particle is a modified hepatitis virus particle or a modified pestivirus particle, and 
       wherein the partially delipidated viral particle comprises an envelope comprising proteins and is obtained by treating a lipid-containing viral particle by a process consisting essentially of treating the lipid-containing viral particle with an organic solvent that is not a detergent, a surfactant or β-propiolactone. 
     
     
         2 . The modified viral particle of  claim 1 , wherein the organic solvent is an alcohol, an ether, an amine, a hydrocarbon, or a combination thereof. 
     
     
         3 . The modified viral particle of  claim 2 , wherein the ether is C4 to C8 ether and the alcohol is a C1 to C8 alcohol. 
     
     
         4 . A vaccine composition, comprising at least a partially delipidated viral particle and a pharmaceutically acceptable carrier, wherein the partially delipidated viral particle is capable of provoking a positive immune response when administered to a patient, and wherein the partially delipidated viral particle comprises an envelope comprising proteins and is produced by exposing a non-delipidated viral particle to a delipidation process consisting essentially of treating a lipid-containing viral particle with an organic solvent that is not a detergent, a surfactant or β-propiolactone. 
     
     
         5 . The vaccine composition of  claim 4 , wherein the organic solvent is an alcohol, an ether, or a combination thereof. 
     
     
         6 . The vaccine composition of  claim 5 , wherein the ether is C4 to C8 ether and the alcohol is a C1 to C8 alcohol.