Patent ID: 7534609

Claim:
A method of expanding an undifferentiated hemopoietic stem cell population to increase the number of the hemopoietic stem cells without the undifferentiated hemopoietic stem cells undergoing differentiation, the method comprising: (a) culturing stromal cells to confluence in a stationary phase plug-flow bioreactor under continuous flow of 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 stationary phase three-dimensional confluent stromal cell culture; (b) separating a stromal cell conditioned medium from said stationary phase three-dimensional confluent stromal cell culture; (c) collecting said stromal cell conditioned medium; (d) obtaining an undifferentiated hemopoietic stem cell population; (e) adding said undifferentiated hemopoietic stem cell population to a medium containing said stromal cell conditioned medium; and (f) culturing said undifferentiated hemopoietic stem cell populations in a medium containing said stromal cell conditioned medium, thereby expanding the undifferentiated hemopoietic stem cell population to increase the number of undifferentiated hemopoietic stem cells without the undifferentiated hemopoietic stem cells undergoing differentiation to obtain an expanded undifferentiated hematopoietic stem cell population.