Cultures of E1-immortalized cells and processes for culturing the same to increase product yields therefrom

Abstract

The invention provides processes for culturing cells derived from embryonic retinoblast cells immortalized by adenovirus E1 sequences, preferably PER.C6® cells, to improve product yields from such cells. Feed strategies for such cells and cultures with very high cell densities are provided, resulting in high yields of products, such as recombinant antibodies.

1 .- 20 . (canceled)  
   
   
       21 . A culture of human embryonic retina (HER) cells immortalized by adenovirus E1 sequences, wherein said culture of cells comprises at least 10×10 6  cells/ml.  
   
   
       22 . The culture of cells of  claim 21 , wherein said culture of cells comprises at least 12×10 6  cells/ml.  
   
   
       23 . The culture of cells of  claim 22 , wherein said culture of cells comprises at least 15×10 6  cells/ml.  
   
   
       24 . The culture of cells of  claim 23 , wherein said culture of cells comprises at least 20×10 6  cells/ml.  
   
   
       25 . The culture of cells of  claim 24 , wherein said culture of cells comprises at least 30×10 6  cells/ml.  
   
   
       26 . The culture of cells of  claim 25 , wherein said culture of cells comprises at least 40×10 6  cells/ml.  
   
   
       27 . The culture of cells of  claim 21 , wherein at least 80% of the cells are viable.  
   
   
       28 . A culture of cells according to  claim 21 , wherein culture medium is exchanged at a rate of about 0.2-3 culture volumes/day.  
   
   
       29 . The culture of cells of  claim 21 , wherein cells in said culture of cells express a recombinant protein.  
   
   
       30 . The culture of cells of  claim 29 , wherein said cells produce at least 10 pg protein/cell/day.  
   
   
       31 . The culture of cells of  claim 21 , wherein said culture of cells is a batch culture and wherein cells in said culture of cells express a recombinant immunoglobulin with a yield of at least 500 mg/l.  
   
   
       32 . The culture of cells of  claim 30 , wherein said yield is at least 700 mg/l.  
   
   
       33 . The culture of cells of  claim 29 , wherein said culture of cells is a perfusion or fed-perfusion culture and wherein said recombinant protein is an immunoglobulin that is expressed with a yield of at least 150 mg/l/day.  
   
   
       34 . The culture of cells of  claim 21 , wherein said cells are PER.C6 cells as represented by the cells deposited under ECACC No. 96022940.  
   
   
       35 . The culture of cells of  claim 21 , wherein said culture of cells is a suspension culture.  
   
   
       36 .- 41 . (canceled)