Fetal liver and bone marrow JORO 75+ lymphocyte progenitors are precursors of CD4+8- TCR/CD3- early thymocytes.
We show here that cell sorter purified JORO 75+ lymphocyte progenitors from fetal liver or bone marrow of adult mice give rise in vitro to CD4+8- T cell receptor (TCR)/CD3- early thymocytes and CD4+8- TCR/CD3+ thymocyte subsets after coculture with the EH6 subcapsular thymic epithelial cell line, recombinant interleukin 7 (rIL-7) and F (supernatants from the FLS4.1 fetal liver stromal cell line). We find that in cultures that had additionally received rIL-2, CD4-8+ TCR/CD3+ cells were also generated. The results strongly suggest that fetal liver and marrow JORO 75+ lymphocyte progenitors are precursors to the early CD4+8- TCR/CD3- intrathymic population previously identified in the adult mouse. The EH6 subcapsular thymic epithelial cell line should facilitate the study of the molecular events responsible for very early stages of T cell development including T lymphocyte-lineage commitment.
Golunski
E
E
Department of Immunology, University of Texas, MD Anderson Cancer Center, Houston 77030.
Palacios
R
R
D000818:Animals; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D017252:CD3 Complex; D015704:CD4 Antigens; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D016827:CD8 Antigens; D002460:Cell Line; D005333:Fetus / Q000166:cytology / Q000276:immunology; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D008099:Liver / Q000166:cytology* / Q000196:embryology / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D011948:Receptors, Antigen, T-Cell
D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D011948:Receptors, Antigen, T-Cell