title: Efficient thymic immigration of B220+ lymphoid-restricted bone marrow cells with T precursor potential.
abstract: Using a human CD25 reporter transgene controlled by regulatory sequences from the gene encoding pre-T cell receptor alpha, we identified a common lymphocyte precursor (CLP-2) population that, in contrast to the previously identified CLP-1 population, was c-Kit-B220+. In short-term culture, the CLP-2 could be derived from the CLP-1 subset, and contained cells that in clonogenic assays were assessed to be bipotent precursors of T and B cells. Intravenous injection of bone marrow cells yielded a selective accumulation of CLP-2 thymic immigrants that in thymic organ culture generated mature alphabeta T cells. Although the CLP-2 subset may represent the most differentiated population with T cell potential before commitment to the B cell lineage, other subsets of thymic immigrants capable of generating T cells may exist.
authors.affiliation: Department of Pathology, Harvard Medical School, Dana-Farber Cancer Institute Boston, Massachusetts, 02115, USA.
authors.forename: Colin H
authors.initials: CH
authors.lastname: Martin
authors.forename: Iannis
authors.initials: I
authors.lastname: Aifantis
authors.forename: M Lucila
authors.initials: ML
authors.lastname: Scimone
authors.forename: Ulrich H
authors.initials: UH
authors.lastname: von Andrian
authors.forename: Boris
authors.initials: B
authors.lastname: Reizis
authors.forename: Harald
authors.initials: H
authors.lastname: von Boehmer
authors.forename: Fotini
authors.initials: F
authors.lastname: Gounari
mesh_terms: D000818:Animals; D018941:Antigens, CD19 / Q000235:genetics / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D001854:Bone Marrow Cells / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation / Q000276:immunology; D019070:Cell Lineage; D002465:Cell Movement / Q000276:immunology; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000276:immunology; D012313:RNA / Q000737:chemistry / Q000235:genetics; D015375:Receptors, Interleukin-2 / Q000235:genetics / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*
chemical_list: D018941:Antigens, CD19; D015375:Receptors, Interleukin-2; D012313:RNA; D019009:Proto-Oncogene Proteins c-kit; D017493:Leukocyte Common Antigens