title: Cloning thymic precursor cells: demonstration that individual pro-T1 cells have dual T-NK potential and individual pro-T2 cells have dual alphabeta-gammadelta T cell potential.
abstract: Thymic progenitors have the capacity to generate alphabeta T cells, gammadelta T cells, and NK cells. To determine whether these three lineages derive from a single precursor cell or from different precursors, a procedure was developed for cloning precursor cells from mouse embryonic thymus. The progeny of each pro-T cell clone were then tested for the potential to generate alphabeta, gammadelta, and NK cells. Of these precursor clones, about half displayed dual potential, developing into either T cells or NK cells, demonstrating the existence of a common T/NK precursor cell in the thymus. The other half of the clones were restricted to T cell development. No precursor clones were restricted to NK development. The common T/NK precursors were shown to be of the pro-T1 (CD25(-)) stage whereas the T-restricted precursors were shown to be of the later pro-T2 (CD25(+)) stage. Both alphabeta and gammadelta T cells were generated from all clones derived from either pro-T1 or -T2 precursors. This shows that commitment of a cell to the alphabeta versus gammadelta lineages does not precede rearrangement of the TCR genes (which occurs immediately after the pro-T2 stage).
authors.affiliation: Laboratory of Immunoregulation, Division of Basic Sciences, National Cancer Institute, Frederick, Maryland 21702-1201, USA.
authors.forename: C K
authors.initials: CK
authors.lastname: Lee
authors.forename: K
authors.initials: K
authors.lastname: Kim
authors.forename: T M
authors.initials: TM
authors.lastname: Geiman
authors.forename: W J
authors.initials: WJ
authors.lastname: Murphy
authors.forename: K
authors.initials: K
authors.lastname: Muegge
authors.forename: S K
authors.initials: SK
authors.lastname: Durum
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage / Q000276:immunology*; D002999:Clone Cells; D046508:Culture Techniques / Q000379:methods*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology*; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000196:embryology / Q000276:immunology*