title: Cytokine requirement for the development of T-lymphoid lineage potential in clonal lymphohaematopoietic progenitors in vitro.
abstract: The early process of T-cell development prior to thymic colonization has been poorly investigated because of the lack of a sensitive assay. We have developed a two-step in vitro culture system by combining a clonal culture with a fetal thymus organ culture (FTOC) and analysed the early development of T cells from lymphohaematopoietic progenitors. Cells of immature colonies derived from bone marrow cells of 5-fluorouracil (5FU)-treated mice using various combinations of early acting cytokines were transferred into a FTOC. All the combinations of stem cell factor (SCF), interleukin (IL)-3 and IL-6 capable of inducing colony formation supported T-cell generation. IL-11 and the Flt3 ligand possessed T-lineage promotional effects similar to IL-6 and SCF respectively. However, there were some quantitative differences in the final T-cell yield among cytokine combinations. Thus, the commitment towards T lineage in lymphohaematopoietic progenitors may be an event determined intrinsically rather than induced by specific stimuli, but there may be a hierarchy between the activity of cytokines in further development. Furthermore, we examined the T-lineage potential of individual colonies derived from Lin(-)c-Kit(+)Sca-1(+) cells clone-sorted from post-5FU marrow cells. No colonies that contained only myelocytic progenitors showed T-lineage potential, but 23.3% of colonies with a haematopoietic multipotentiality did. Therefore, the divergence of the T lineage from other lineages such as myeloid potential may occur at an early stage of the hierarchy of haematopoiesis. The proposed method should prove valuable for exploring the molecular and cellular changes that occur during early T-cell development before thymic colonization.
authors.affiliation: Department of Clinical Oncology, The Institute of Medical Science, The University of Tokyo, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Ma
authors.forename: F
authors.initials: F
authors.lastname: Yang
authors.forename: A
authors.initials: A
authors.lastname: Kaneko
authors.forename: A
authors.initials: A
authors.lastname: Manabe
authors.forename: R
authors.initials: R
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Asano
authors.forename: T
authors.initials: T
authors.lastname: Nakahata
authors.forename: K
authors.initials: K
authors.lastname: Tsuji
mesh_terms: D000818:Animals; D019070:Cell Lineage; D002999:Clone Cells; D016207:Cytokines / Q000494:pharmacology*; D004921:Erythropoietin / Q000494:pharmacology; D005260:Female; D005472:Fluorouracil; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D007166:Immunosuppressive Agents; D017370:Interleukin-11 / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D015851:Interleukin-7 / Q000494:pharmacology; D008297:Male; D008565:Membrane Proteins / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D009924:Organ Culture Techniques; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D019089:Stem Cell Factor / Q000494:pharmacology; D013234:Stem Cells / Q000502:physiology*; D013601:T-Lymphocytes / Q000502:physiology*; D013926:Thrombopoietin / Q000494:pharmacology; D013950:Thymus Gland / Q000196:embryology
chemical_list: D016207:Cytokines; D007166:Immunosuppressive Agents; D017370:Interleukin-11; D007377:Interleukin-3; D015850:Interleukin-6; D015851:Interleukin-7; D008565:Membrane Proteins; D011994:Recombinant Proteins; D019089:Stem Cell Factor; C084881:flt3 ligand protein; D004921:Erythropoietin; D016179:Granulocyte Colony-Stimulating Factor; D013926:Thrombopoietin; D005472:Fluorouracil