Patent 7531351 was granted and assigned to ProBioGen AG on May, 2009 by the United States Patent and Trademark Office.
Initiation of growth and cultivation of cells can be performed by introducing the cells into culture compartments of a liquid-gas-phase exposure bioreactor containing a supply chamber in which there are disposed hollow-filament membranes having an inside diameter of no larger than 5 mm, wherein an inner volume of said hollow-filament membranes forms the culture compartments. Approximately one half of the supply chamber is filled with a nutrient medium and a remainder is filled with a gas mixture. Perfusion of medium and gas is turned on simultaneously or separately. The hollow-filament membranes and the cells contained therein are cyclically exposed to the gas or liquid phase.