Abstract
A novel continuous-flow cell separation method can separate a large number of cells into five fractions according to their densities. It has been developed for application to the transfusion medicine. In the past the capability of the method has been demonstrated on the separation of nucleated cells from human peripheral blood. Nucleated cells (>107) present among a large population of erythrocytes (>1010) were separated from 10ml of peripheral blood for about 100 minutes. At the last annual meeting, we reported that a variety of progenitor cells such as CFU-E, CFU-GM and CFU-GEMM were found among harvested cells without the loss of viability. In the batch method, low-density nucleated cells are separated by density gradient centrifugation from a much smaller volume of blood. Generally, a polysucrose solution, adjusted to a density of 1.077, is used for the preparation of cell samples for the colony-forming cell assay. Therefore, we compared the performance between the above two separation methods. Using the batch method, mononuclear cells trapped above the interface and within the polysucrose layer were collected and examined. CFU-GEMMs, multi-potential progenitor cells, were found not only at the interface, but also within the polysucrose layer which was usually discarded. This result suggested that the batch method may lose substantial amount of progenitor cells whereas a novel cell separation method could prevent the potential loss of progenitor cells. [J Physiol Sci. 2007;57 Suppl:S215]
