Process for inactivating prions in lipoproteins

Abstract

A process for treatment of a purified lipoprotein material to inactivate prions in a manner that does not substantially adversely affect the biological activity of the lipoprotein is provided that includes treating the lipoprotein prion composition with a solution of base at a pH of between 10 and 13 for a sufficient time to cause inactivation.

We claim:  
     
         1 . A process for treatment of a purified lipoprotein material to inactivate prions in a manner that does not substantially adversely affect the biological activity of the lipoprotein or cholesterol, that includes treating the material with a solution of base at a pH of between 10 and 13 for a sufficient time to cause prion inactivation.  
     
     
         2 . The process of  claim 1 , carried out at approximately room temperature.  
     
     
         3 . The process of  claim 1 , wherein the base is sodium hydroxide.  
     
     
         4 . The process of  claim 1 , wherein the base is potassium hydroxide.  
     
     
         5 . The process of  claim 1 , wherein the base is hydroxide ion.  
     
     
         6 . The process of  claim 1 , wherein the base is an ammonium ion or amine.  
     
     
         7 . The process of  claim 1 , wherein the base is in concentration of between 0.1 and 1N solution.  
     
     
         8 . The process of  claim 1 , wherein the time from initial contact is up to 10 hours.  
     
     
         9 . The process of  claim 1 , wherein the lipoprotein is treated for at least 2 hours.  
     
     
         10 . The process of  claim 1 , wherein the lipoprotein is treated for at least 4 hours.  
     
     
         11 . The process of  claim 1 , wherein the lipoprotein is treated for at least 6 hours.  
     
     
         12 . The process of  claim 1 , wherein the lipoprotein is treated for at least 8 hours.  
     
     
         13 . The process  claim 1 , wherein the lipoprotein is treated for at least 10 hours.  
     
     
         14 . The process of  claim 1 , wherein the lipoprotein is maintained at a pH of about 12 for about 8 hours.  
     
     
         15 . The process of  claim 1 , wherein the lipoprotein is treated at a temperature between between about 16° C. and about 24° C.  
     
     
         16 . The process of  claim 1 , wherein concentration is between 10 and 3,500 mg/dL.  
     
     
         17 . The process of  claim 1 , wherein the concentration is between 50 and 500 mg/dL.  
     
     
         18 . The process of  claim 1 , further comprising after treatment with the base for a sufficient time to allow a desired degree of prion inactivation, adjusting the pH to neutral or another desired pH, using a pH-adjusting agent that does not adversely affect the biologic material.  
     
     
         19 . The process of  claim 1 , wherein the purified lipoprotein (other than contaminating prion) consists essentially of lipoprotein material and solvent.  
     
     
         20 . The process of  claim 1 , wherein the lipoprotein material is substantially pure.  
     
     
         21 . The process of  claim 1 , wherein the lipoprotein is in a solvent selected from water, saline, or buffer.  
     
     
         22 . The process of  claim 1 , wherein the purified lipoprotein material contains cholesterol.  
     
     
         23 . The process of  claim 1 , wherein the lipoprotein includes material selected from the group consisting of a triglyceride, a fatty acid and a phospholipid.  
     
     
         24 . A process for removing prions from a lipoprotein material solution by contacting the solution with an adsorbant that binds more tightly to the lipoprotein than to the prion.  
     
     
         25 . The process of  claim 24 , wherein the adsorbant is silica.  
     
     
         26 . The process of  claim 24 , wherein the lipoprotein material is mixed with silica at a pH that does not cause the removal of the lipoprotein from the silica.  
     
     
         27 . The process of  claim 26 , wherein the pH is between 6 and 8.  
     
     
         28 . The process of  claim 26 , further comprising separating the silica/lipoprotein material particulate from the prion-containing liquid by filtration.  
     
     
         29 . The process of  claim 28 , further comprising removing the lipoprotein material from the silica.  
     
     
         30 . The process of  claim 29 , wherein the lipoprotein material is removed via an elevated pH.  
     
     
         31 . The process of  claim 29 , wherein the removal is carried out by passing a high pH buffered solution through the lipoprotein-adsorbent complex until the lipoprotein material is substantially removed from the adsorbent.  
     
     
         32 . The process of  claim 24 , wherein the lipoprotein material contains cholesterol.  
     
     
         33 . The process of  claim 24 , wherein the lipoprotein material includes material selected from the group consisting of a triglyceride, a fatty acid and a phospholipid.