Unravelling stem cell dynamics by lineage tracing

The rules governing cell fate choice are key to understanding the mechanisms that regulate stem cell behaviour in development and homeostasis and to identifying the factors leading to their dysregulation in disease.Lineage-tracing approaches are essential to obtain information on the long-term self-renewal potential and fate choice of stem and progenitor cell populations.Population-based methods involving the incorporation of thymidine analogues, such as 5-bromodeoxyuridine (BrdU), or the dilution of histone 2B (H2B)–GFP, provide quantitative information on proliferation kinetics and fate specification of cell populations.Lineage-tracing methods based on the use of transgenic animal models provide access to quantitative information on the activity, potency and fate choice of individual stem cells and their progeny.The quantitative analysis of lineage-tracing data following inducible genetic labelling has contributed to the understanding of the proliferative hierarchy and fate behaviour of stem and progenitor cell populations in the mouse interfollicular epidermis and the intestinal epithelium in homeostasis.Lineage-tracing methods can also be used to study the renewal and lineage potential of precursors in adult tissue, as well as during embryonic and postnatal development.Lineage-tracing assays in animal models provide new quantitative insights into the fate behaviour and tumour-maintaining potential of cells within solid tumours.