Peripheral T cell populations are maintained by production of naive T cells in the thymus,
clonal expansion of activated cells, cellular self-renewal (or homeostatic proliferation), and
density dependent cell life spans. A variety of experimental techniques have been employed
to quantify the relative contributions of these processes. In modern studies lymphocytes are
typically labeled with 5-bromo-2′-deoxyuridine (BrdU), deuterium, or the fluorescent dye
carboxy-fluorescein diacetate succinimidyl ester (CFSE), their division history has been …