Patent ID: 7858296

Claim:
A method of preparing a cell concentrate comprising: providing a physiological fluid which has not been previously subjected to centrifugation and which comprises platelets, plasma, nucleated cells and red blood cells, combining a hypotonic fluid with the physiological fluid, the hypotonic fluid being in an amount which does not cause the cells to lyse in the physiological fluid/hypotonic fluid combination, subjecting the combined physiological fluid/hypotonic fluid to a first filtration device to produce a filter retentate, which is a first product, and a permeate fluid, wherein said filter retentate comprises platelets and nucleated cells per unit volume greater than in the physiological fluid, and wherein said permeate fluid comprises plasma and red blood cells, removing the filter retentate from the filter, and subjecting the filter retentate to a second filtration device to produce a cell concentrate, which is a second product.