The thymus and T-cell commitment: the right niche for Notch?
The current dogma is that the thymus is colonized by progenitors that retain the capacity to generate both T cells and B cells, and that intrathymic Notch signalling determines lineage choice so that T cells, rather than B cells, develop in the thymus. However, evidence is now accumulating to indicate that, at least during fetal life, this is not the case. Rather, it now seems that the fetal thymus is colonized by progenitors that have already made the T-cell versus B-cell lineage choice. We propose an alternative role for Notch signalling in the thymus, which is not to mediate this choice but instead to reveal it by supporting further T-cell differentiation in the thymic microenvironment.
Jenkinson
Eric J
EJ
MRC Centre for Immune Regulation, Division of Immunity and Infection, Institute for Biomedical Research, Medical School, University of Birmingham, Birmingham B15 2TT, UK. e.j.jenkinson@bham.ac.uk
Jenkinson
William E
WE
Rossi
Simona W
SW
Anderson
Graham
G
D000818:Animals; D002454:Cell Differentiation / Q000276:immunology*; D019070:Cell Lineage / Q000276:immunology; D006801:Humans; D018448:Models, Immunological; D051880:Receptors, Notch / Q000276:immunology* / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology
D051880:Receptors, Notch