Psoralen-inactivated dengue virus vaccine and method of preparation

Abstract

A method to inactivate virus for vaccine uses by exposing said virus to a predetermined concentration of an inactivating psoralen, and exposing said virus to a preselected intensity of ultraviolet radiation for a time period sufficiently long to render the virus non-infectious but less than that which would result in degradation of its antigenic characteristics.

We claim: 
     
         1 . A vaccine prepared by psoralen inactivation, comprising one or more types of inactivated viruses. 
     
     
         2 . The vaccine of  claim 1 , wherein said inactivated virus comprising an Arbovirus. 
     
     
         3 . The vaccine of  claim 2 , wherein said inactivated virus comprising a dengue virus. 
     
     
         4 . The vaccine of  claim 3 , wherein said dengue virus is selected from the serotype consisting: dengue-1, dengue-2, dengue-3, dengue-4, and a combination thereof. 
     
     
         5 . The vaccine of  claim 1 , wherein said vaccine further comprises an adjuvant. 
     
     
         6 . The vaccine of  claim 5 , wherein said adjuvant is aluminum hydroxide or ASO4. 
     
     
         7 . The vaccine of  claim 1 , wherein said vaccine is prepared by:
 a) exposing said virus to an inactivating psoralen, wherein said psoralen is selected from the group consisting of 4′-Aminomethyltrioxalen hydrochloride (AMT), 8-Methoxypsoralen (8-MOP), 4, 5′,8-Trimethylpsoralen (TMP) and a combination thereof, and   b) exposing said virus to a preselected intensity of an ultraviolet radiation for 5 to 30 minutes, which is sufficiently long to render the virus non-infectious but would notresult in degradation of its antigenicity.   
     
     
         8 . The vaccine of  claim 7 , wherein said inactivating psoralen is added to a medium containing said live virus in 1-4 additions. 
     
     
         9 . The vaccine of  claim 8 , wherein said psoralen is added to the medium at a concentration of 1-100m/ml. 
     
     
         10 . The vaccine of  claim 8 , wherein the concentration of said psoralen is 5-25 μg/ml. 
     
     
         11 . The vaccine of  claim 7 , wherein said ultraviolet radiation exposure is 5 to 10 minutes. 
     
     
         12 . The vaccine of  claim 7 , wherein the intensity of ultraviolet radiation is 150 μW/cm2 to 200 mW/cm2. 
     
     
         13 . The vaccine of  claim 7 , wherein the intensity of ultraviolet radiation is 150 μW/cm2 to 1500 μW/cm2. 
     
     
         14 . The vaccine of  claim 7 , wherein temperature of said medium is maintained below 250 C during said ultraviolet irradiation exposure. 
     
     
         15 . A method for immunizing a subject against viral infection, comprising administering a vaccine of  claim 1 . 
     
     
         16 . The method of  claim 15 , wherein said vaccine is administered in a route selected from the group consisting: oral, transdermal, epidermal, transcutaneous, and mucosal. 
     
     
         17 . The method of  claim 15 , wherein said vaccine is administered with or without an adjuvant. 
     
     
         18 . The method of  claim 15 , further comprising one or more boosting dose of said vaccine.