Static cell culture maintenance system

A method of maintaining animal cells in vitro in a substantially arrested state of proliferation with continuous secretion of cell product which comprises:

• (a) suspending said cells in a semi-rigid matrix of finely divided particles disposed in a cell culture reactor chamber and having interstices for passage of fluid nutrient medium,
• (b) supplying fresh nutrient medium for said cells by passing said nutrient medium through an external inlet in the reactor into the lumen of at least one first porous tube disposed in said chamber substantially throughout the length or width of said matrix and perfusing said nutrient medium through the walls of said porous tube into said matrix,
• (c) withdrawing expended nutrient medium and cell product from said matrix by perfusing through the walls of at least one second porous tube disposed in said chamber substantially throughout the length or width of said matrix and passing said spent medium and cell product through an external outlet in said reactor, said second porous tube having a pore size larger than the pore size of said first porous tube, wherein the pore size of the first porous tube is from about 0.2 to about 5.mu. and wherein the pore size of the second porous tube is from about 10.mu. to about 150.mu. and said first and second porous tubes having closures at their ends within said chamber which are distal to the exterior culture medium inlet and outlet means, and
• (d) supplying oxygenated gaseous medium for said cells by perfusing into said chamber through the walls of at least one selectively-permeable tubular membrane disposed in said matrix substantially throughout the expanse of said matrix and having openings at both ends of its lumen for inlet and outlet of said gas to and from the outside of said reactor.