Single cell sorting and cloning

Cell sorters now allow the selection of cells and other bodies according to a range of quite diverse criteria. The additional refinement that allows t he sorting of individual cells based on these criteria has seen application in many fields of research. Single cells may be sorted for microscopy, for culture and for genetic analysis by way of single cell PCR (polymerase cha in reaction). In practical terms, in the setting up of an instrument for si ngle cell sorting, there are additional requirements to ensure that each de tected event is indeed a single cell or body, that this cell can be reliabl y sorted via saline droplet, separate from its fellow travelers, that the a iming of the droplet deflection is sufficiently precise to find the target vessel and that the cell will be undamaged on arrival. Among the diverse re ported applications of the technique, two fields which have benefited great ly are lymphocyte development and haemopoiesis. In the former case, the ana lysis of gene rearrangements in lymphocytes, both in the pre- and post-anti genic phases of development, has been enabled by the combined technologies of single cell sorting and PCR. It is argued that such experiments could no t have been done without that partnership. In a similar way, the single cel l sorting technique has been found to be the perfect way to demonstrate pre cursor/progeny relationships between haemopoietic cells and, further, to de monstrate rigorously the effects of particular cytokines on the haemopoieti c system. (C) 2000 Elsevier Science B.V. All rights reserved.