US 5,981,211 A · Maintaining cells for an extended time by entrapment in a contracted matrix

Abstract

Methods of maintaining animal cells for product production, for supporting hepatocyte function and viability to treat a patient suffering from hepatic failure and for preserving tissue-specific function of mammalian cells are carried out with a bioreactor containing a feed and waste chamber and a cell chamber separated by a selectively permeable membrane. Within the cell chamber, a biocompatible contracted three-dimensional gel matrix entraps animal cells or genetic modifications thereof, and a liquid phase contains a concentrated solution of the cell product. The bioreactor uses only two chambers to achieve three distinct zones within the bioreactor. The bioreactor can be of either hollow fiber or flat-bed configuration. In the configuration using hollow fibers, the two fluid paths correspond to the cavity surrounding the hollow fibers (the extracapillary space), and to the lumens of the hollow fibers themselves. Both fluid paths have inlet and outlet ports. Communication between the two fluid paths is across the permeable medium--the hollow fiber material. To prepare a bioartificial liver, hepatocytes are inoculated into the hollow fibers in a solution which quickly forms a highly porous gel. The gel subsequently contracts, leaving an open channel within the hollow fiber adjacent to the gel core entrapped hepatocytes. This channel can be perfused with nutrient media for hepatocytes. The channel can also serve as a waste stream to remove toxins that the hepatocytes have modified to a water soluble form.

Claims22

Dependent claims

A method for maintaining animal cells and genetically altered derivative cells thereof in vitro over a sustained period of time for continuous production of a desired cell product comprising the steps of:

(a) introducing a matrix precursor including said cells into a cell chamber;
(b) inducing said matrix precursor including said cells to form an insoluble cell-biocompatible matrix means including said cells;
(c) contracting said insoluble cell-biocompatible matrix means including said cells in situ within said cell chamber approximately one-third of the original volume occupied within said cell chamber by said matrix precursor and said cells to form a contracted insoluble matrix entrapping said cells and another chamber comprising a liquid phase for accumulating the desired cell product;
(d) supplying nutrient medium of said cells by passing said nutrient medium through an inlet means leading to a chamber for cell nutrient and cell waste, said chamber for cell nutrient and cell waste separated from said cell chamber by a selectively permeable membrane, and perfusing said nutrient medium through said membrane into said cell chamber;
(e) withdrawing expended nutrient medium and cell waste which have traveled from said cell chamber to said chamber for cell nutrient and cell waste through said permeable membrane from the chamber for cell nutrient and cell waste through an outlet means;
and
(f) withdrawing the desired cell product from said cell chamber through a second outlet means in flow communication with said cell chamber.

4 more elements

A method of supporting hepatocyte function and viability for treating a patient suffering from hepatic failure comprising the steps of:

(a) introducing a matrix precursor including hepatocytes into a cell chamber;
(b) inducing said matrix precursor including said hepatocytes to form an insoluble hepatocyte-biocompatible matrix means including said hepatocytes:
(c) contracting said insoluble hepatocyte-biocompatible matrix means including said hepatocytes in situ within said cell chamber approximately one-third of the original volume occupied within said cell chamber by said matrix precursor and said hepatocytes to form a contracted insoluble matrix entrapping said hepatocytes and another chamber comprising a liquid phase within said cell chamber;
(d) supplying a fluid flow of blood or plasma from said patient through a first fluid flow means to said cell chamber containing said contracted insoluble matrix entrapping said hepatocytes such that communication between said blood or plasma and said hepatocytes is exclusively through a selectively permeable membrane to allow diffusion of waste products through said membrane from said blood or plasma for detoxification by said hepatocytes;
and
(e) supplying a fluid flow of a hepatocyte support medium containing growth factors for said hepatocytes through a second fluid flow means such that said medium flows through said another chamber in said cell chamber in contact with said contracted insoluble matrix entrapping said hepatocytes and separated from said blood or plasma by said membrane to effect hepatocyte waste removal and support hepatocyte function and viability.

3 more elements

A method of preserving tissue-specific function of mammalian cells comprising the steps of:

(a) introducing a matrix precursor including said mammalian cells into a cell chamber;
(b) inducing said matrix precursor including said cells to form an insoluble cell-biocompatible matrix means including said cells;
(c) contracting said insoluble cell-biocompatible matrix means including said cells in situ within said cell chamber approximately one-third of the original volume occupied within said cell chamber by said matrix precursor and said cells to form a contracted insoluble matrix entrapping said cells and another chamber comprising a liquid phase within said cell chamber;
(d) supplying a fluid flow of perfusing medium through a first fluid flow means to said cell chamber containing said contracted insoluble matrix entrapping said cells such that communication between said perfusing medium and said cells is exclusively through a selectively permeable membrane to support cell function and viability of said cells;
and
(e) supplying a fluid flow of liquid medium through a second fluid flow means such that said liquid medium flows through said another chamber within said cell chamber in contact with said contracted insoluble matrix entrapping said cells and separated from said perfusing medium by said membrane to effect waste removal and support cell function and viability.

3 more elements

Dependencies are inferred from the claim text.

Maintaining cells for an extended time by entrapment in a contracted matrix

Life of this patent

Maintaining cells for an extended time by entrapment in a contracted matrix

Life of this patent

Abstract

Claims22