Chapter 20 Strategies for Rare Cell Detection and Isolation

Abstract

This chapter discusses a fairly nontechnical, practical, and pragmatic way what one can do with conventional flow cytometry and cell sorting instrumentation to analyze and sort rare cells. It also attempts to point out some of the methodological pitfalls. Most flow cytometers use cell light scatter as a default system trigger for obvious reasons. All cells should have a light scatter signal, whereas only some cells will be fluorescent. Light scatter can also be used to eliminate debris at the analog level prior to digital signal processing, which can greatly reduce the effective dead time of the instrument. The chapter demonstrates that with sensitivity to the problems of rare cell analysis and sorting, it is possible to analyze rare and, in some cases, ultrarare cells. Impure sorts may suffice for many situations. The theoretical discussions in this chapter are designed to enable experimenters to determine whether their experiments are at all feasible. Each biological application should be approached pragmatically; the analysis or sort may not need to be perfect, only good enough to answer the question at hand.