Patent ID: 6911201

Claim:
A method of expanding undifferentiated hemopoietic stem cells to increase the number of the hemopoietic stem cells, the method comprising the steps of: (a) culturing in a stationary phase plug-flow bioreactor a stromal cell culture under continuous flow of a culture medium on a substrate in the form of a sheet, said substrate including a non-woven fibrous matrix forming a physiologically acceptable three-dimensional network of fibers to thereby generate a three dimensional stromal cell culture; and (b) seeding undifferentiated hemopoietic stem cells into said stationary phase plug-flow bioreactor including said three dimensional stromal cell culture and under said continuous flow of said culture medium, thereby expanding the undifferentiated hemopoietic stem cells to increase the number of the hemopoietic stem cells without the hemopoietic stem cells undergoing differentiation to obtain expanded undifferentiated hemopoietic stem cells.