Identification and characterization of thymic epithelial progenitor cells.
T cell differentiation and repertoire selection depend critically on several distinct thymic epithelial cell types, whose lineage relationships are unclear. We have investigated these relationships via functional analysis of the epithelial populations within the thymic primordium. Here, we show that mAbs MTS20 and MTS24 identify a population of cells that, when purified and grafted ectopically, can differentiate into all known thymic epithelial cell types, attract lymphoid progenitors, and support CD4(+) and CD8(+) T cell development in nude mice. In contrast, other epithelial populations in the thymic primordium can fulfill none of these functions. These data establish that the MTS20(+)24(+) population is sufficient to generate a functional thymus in vivo and thus argue strongly that all thymic epithelial cell types derive from a common progenitor cell.
Centre for Genome Research and Institute for Cell, Animal and Population Biology, The University of Edinburgh, King's Buildings, West Mains Road, Edinburgh EH9 3JQ, United Kingdom.
Andrea R
AR
Bennett
Alison
A
Farley
Natalie F
NF
Blair
Julie
J
Gordon
Linda
L
Sharp
C Clare
CC
Blackburn
D000818:Animals; D000911:Antibodies, Monoclonal; D015415:Biomarkers; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D002454:Cell Differentiation; D004847:Epithelial Cells / Q000166:cytology; D005260:Female; D005434:Flow Cytometry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008819:Mice, Nude; D010641:Phenotype; D013234:Stem Cells / Q000166:cytology*; D013601:T-Lymphocytes / Q000166:cytology*; D013950:Thymus Gland / Q000166:cytology*
D000911:Antibodies, Monoclonal; D015415:Biomarkers