Method for Proliferation of Cells Within a Bioreactor Using a Disposable Pumphead and Filter Assembly

Abstract

A method for promoting biological activity uses a filter system to increase cell production of a fed batch bioreactor. The filter system cycles bioreactor fluid through a hollow fiber tangential flow filter which separates metabolic wastes (as well as proteins) from cells produced in bioreactor and returned to fed batch bioreactor, improving cell production in the fed batch bioreactor. The filter system includes a disposable pump and filter, and a reusable control system. The pump is a low shear gamma stable pump gently cycling bioreactor fluid through the filter with minimal damage to the cells produced in the bioreactor. The pumphead and hollow fiber tangential flow filter are disposable. The pump motor is part of the control system and is reusable. The pumphead and filter are provided as an assembled and pre-sterilized unit allowing simple and quick attachment to the fed batch bioreactor, and simple and quick disposal.

1 . A thick walled hollow fiber tangential flow filter, comprising:
 a polyethylene wall having a thickness of 1.2-1.7 mm, said wall defining a plurality of tortuous paths therethrough, said tortuous paths comprising narrowing channels and settling zones.   
     
     
         2 . A method of filtration of a bioreactor fluid, comprising:
 circulating a bioreactor fluid through a thick walled hollow fiber tangential flow filter according to  claim 1 , thereby separating the bioreactor fluid into a retentate flow comprising the cells that is returned from the tangential flow filter through the return tubing to the bioreactor and a permeate flow.   
     
     
         3 . A system for proliferation of cells within a bioreactor, comprising: (a) a bioreactor vessel containing bioreactor fluid, the bioreactor fluid comprising: cells residing in the bioreactor vessel, the cells including cells produced in the bioreactor vessel; additional material including at least one of waste material, expressed proteins and viruses of interest residing in the bioreactor vessel; (b) bioreactor feed tubing in fluid communication with the bioreactor vessel, (c) retentate return tubing in fluid communication with the bioreactor vessel, (d) a disposable filtering system configured for attachment to the bioreactor vessel and comprising in serial order of flow: a first aseptic connector; first bioreactor fluid flow tubing connected to the first aseptic connector; a disposable pumphead connected to the first bioreactor fluid flow tubing; second bioreactor fluid flow tubing connected to the disposable pumphead; a thick walled hollow fiber tangential flow filter according to  claim 1  connected to the second bioreactor fluid flow tubing; permeate tubing connected to a permeate port of the thick walled hollow fiber tangential flow filter; third bioreactor fluid flow tubing connected to a retentate port the thick walled hollow fiber tangential flow filter; a third connector attached to the third bioreactor fluid flow tubing in fluid communication with an interior of the third bioreactor fluid flow tubing; and a second aseptic connector connected to the third bioreactor fluid flow tubing; and (e) a reusable control system including a reusable pump motor configured for cooperation with the disposable pumphead. 
     
     
         4 . A method for proliferation of cells within a bioreactor using the system of  claim 3 , the method comprising:
 circulating the bioreactor fluid through the thick walled hollow fiber tangential flow filter; thereby separating the bioreactor fluid into a retentate flow comprising the cells that is returned from the thick walled hollow fiber tangential flow filter through the retentate return tubing to the bioreactor vessel and a permeate flow comprising the material that is removed from the thick walled hollow fiber tangential flow filter through the permeate tubing.   
     
     
         5 . The method of  claim 4 , further comprising:
 aseptically connecting the bioreactor feed tubing to the first aseptic connector;   aseptically connecting the retentate return tubing to the second aseptic connector;   engaging the disposable pumphead with the reusable pump motor; and   priming the pump head through the third connector.