ABSTRACT
Virtually any method of cell separation that maintains cells in single-cell suspensions can be used to enrich samples in a particular subpopulation before flow sorting. Examples include various types of centrifugal separation, immunomagetic separation, immunoabsorption, and selective lysis of unwanted cells. Since most other methods allow the sample to be efficiently processed in bulk, flow sorting is best used as a last step. A recent example of the use of immunomagnetic separation before sorting is described by Olweus (28). CD34+ bone marrow prepartions were made 90% pure with 70-80% recover ies before sorting. It is also sometimes useful to do “two-pass” flow sorting, by first running the sample through at a high rate in enrichment mode and then resorting the enriched sample in a high-purity mode.
