Neonatal, moribund and undead T cells: the role of the liver in T cell development.
T lymphocytes may be isolated from the mouse liver, and these cells have been interpreted as immature T cells in an extrathymic development pathway. However, the evidence in favor of this hypothesis is indirect, and there is some evidence that is contradictory. Most significantly, the genes RAG-1 and RAG-2, which are necessary for T cell receptor gene recombination to occur, are not expressed in liver T cells. A subset of liver T cells are undergoing apoptosis, which is the basis of an alternative model in which the liver is a site of peripheral T cell deletion. This model also provides an explanation for the accumulation of abnormal T cells in mice with the lpr mutation.
Crispe
I N
IN
Immunobiology Section, Yale University School of Medicine, New Haven, CT 06510.
Huang
L
L
D000818:Animals; D016923:Cell Death; D002454:Cell Differentiation; D008099:Liver / Q000166:cytology*; D008232:Lymphoproliferative Disorders / Q000235:genetics / Q000276:immunology; D051379:Mice; D008817:Mice, Mutant Strains; D013601:T-Lymphocytes / Q000502:physiology*