Table 1.

Comparison of different methods used to study the generation of new cells in the adult mammalian nervous system

(1) In vivo imaging allows real-time visualization of cells in their natural environment.

(2) Lineage tracing is the utilization of transgenic animals to label single precursor cells and retrospectively analyze the fate choices made by these cells.

(3) Fate mapping entails the study of lineage decision made by populations of cells, utilizing either using transgenic animals or administration of thymidine analogues.

(4) Adenovirus, lentivirus, and retrovirus, when injected into the brain, can be used to trace single cells or population of cells depending on the virus used and the amount of virus injected into the animals.

(5) Transplantation of precursor cells is a useful tool to examine the intrinsic and extrinsic regulation of precursor cells in the brain.

(6–7) Ex vivo methods involve sections in the brain being maintained in culture media, whereas in in vitro studies, the dissociated cells are cultured either as neurospheres or in a monolayer culture system.