Antibodies to hepatitis C virus asialoglycoproteins

Abstract

Two Hepatitis C Virus envelope proteins (E1 and E2) are expressed without sialylation. Recombinant expression of these proteins in lower eukaryotes, or in mammalian cells in which terminal glycosylation is blocked, results in recombinant proteins which are more similar to native HCV glycoproteins. When isolated by GNA lectin affinity, the E1 and E2 proteins aggregate into virus-like particles.

1 - 43 . (canceled)  
     
     
         44 . An isolated antibody specific for a hepatitis C virus (HCV) glycoprotein having mannose-terminated glycosylation, wherein less than about 10% of the total N-linked carbohydrate on said HCV glycoprotein is sialic acid, wherein said HCV glycoprotein is selected from the group consisting of a glycoprotein expressed from the E1 region of HCV, a glycoprotein expressed from the E2 region of HCV, and aggregates thereof.  
     
     
         45 . The antibody of  claim 44 , wherein said HCV glycoprotein is a glycoprotein expressed from the E1 region of HCV.  
     
     
         46 . The antibody of  claim 44 , wherein said HCV glycoprotein is a glycoprotein expressed from the E2 region of HCV.  
     
     
         47 . The antibody of  claim 44 , wherein said HCV glycoprotein is an aggregate of a glycoprotein expressed from the E1 region of HCV and a glycoprotein expressed from the E2 region of HCV.  
     
     
         48 . The antibody of  claim 44 , wherein said HCV glycoprotein is an aggregate of glycoproteins expressed from the E1 region of HCV.  
     
     
         49 . The antibody of  claim 44 , wherein said HCV glycoprotein is an aggregate of glycoproteins expressed from the E2 region of HCV.  
     
     
         50 . The antibody of  claim 44 , wherein the antibody is a polyclonal antibody.  
     
     
         51 . The antibody of  claim 45 , wherein the antibody is a polyclonal antibody.  
     
     
         52 . The antibody of  claim 46 , wherein the antibody is a polyclonal antibody.  
     
     
         53 . The antibody of  claim 47 , wherein the antibody is a polyclonal antibody.  
     
     
         54 . The antibody of  claim 48 , wherein the antibody is a polyclonal antibody.  
     
     
         55 . The antibody of  claim 49 , wherein the antibody is a polyclonal antibody.  
     
     
         56 . An isolated antibody specific for a hepatitis C virus (HCV) glycoprotein having mannose-terminated glycosylation, wherein less than about 10% of the total N-linked carbohydrate on said HCV glycoprotein is sialic acid, wherein said HCV glycoprotein is selected from the group consisting of a glycoprotein expressed from the E1 region of HCV, a glycoprotein expressed from the E2 region of HCV, and aggregates thereof, and further wherein said HCV glycoprotein is produced by the method comprising the steps of: 
 growing a host cell transformed with a structural gene encoding an HCV glycoprotein expressed from the E1 region of HCV or the E2 region of HCV in a suitable culture medium;    causing expression of said structural gene, under conditions inhibiting sialylation; and    isolating said HCV glycoprotein from said cell culture by contacting said HCV glycoprotein with a mannose-binding protein specific for mannose-terminated glycoproteins, and isolating the protein that binds to said mannose-binding protein.    
     
     
         57 . The antibody of  claim 56 , wherein said HCV glycoprotein is a glycoprotein expressed from the E1 region of HCV.  
     
     
         58 . The antibody of  claim 56 , wherein said HCV glycoprotein is a glycoprotein expressed from the E2 region of HCV.  
     
     
         59 . The antibody of  claim 56 , wherein said HCV glycoprotein is an aggregate of a glycoprotein expressed from the E1 region of HCV and a glycoprotein expressed from the E2 region of HCV.  
     
     
         60 . The antibody of  claim 56 , wherein said HCV glycoprotein is an aggregate of glycoproteins expressed from the E1 region of HCV.  
     
     
         61 . The antibody of  claim 56 , wherein said HCV glycoprotein is an aggregate of glycoproteins expressed from the E2 region of HCV.  
     
     
         62 . The antibody of  claim 56 , wherein the antibody is a polyclonal antibody.  
     
     
         63 . The antibody of  claim 57 , wherein the antibody is a polyclonal antibody.  
     
     
         64 . The antibody of  claim 58 , wherein the antibody is a polyclonal antibody.  
     
     
         65 . The antibody of  claim 59 , wherein the antibody is a polyclonal antibody.  
     
     
         66 . The antibody of  claim 60 , wherein the antibody is a polyclonal antibody.  
     
     
         67 . The antibody of  claim 61 , wherein the antibody is a polyclonal antibody.  
     
     
         68 . The antibody of  claim 56 , wherein the structural gene is linked to a sequence encoding a secretion leader that directs the glycoprotein to the endoplasmic reticulum and said conditions inhibiting sialylation comprise inhibiting transport of glycoproteins from the endoplasmic reticulum to the golgi.