The invention pertains to a method of manufacturing a defined population of target cells from a mixed population of blood cells using an apparatus that is configured for processing such cells using a sterile tubing set,wherein the tubing set comprises:(a) an input port configured to receive and deliver the sample to a rotating container,(b) said rotating container, which is configured to rotate about an axis and thereby to apply centrifugal force to a sample contained in a processing chamber in the container so as to separate cells from the sample from other components of the sample；(c) an output port configured to transfer cells processed by the rotating container to a cell separation column；(d) said separation column, which is configured to separate labeled cells from unlabeled cells； and(e) an output port configured to transfer cells separated by the cell separation column to a product collection container.According to the invention, the the method comprises:(1) delivering the sample through the input port into the tubing set； and(2) operating the apparatus such that the sample is processed by the rotating container and by the separation column in the tubing set whereby the target cells are delivered into the product collection container while maintaining sterility of the target cells throughout the aforelisted components of the tubing set.
