title: 'Radioresistant' CD4-CD8- intrathymic T cell precursors differentiate into mature CD4+CD8- and CD4-CD8+ T cells. Development of 'radioresistant' CD4-CD8- intrathymic T cell precursors.
abstract: Using lectin (PNA) and monoclonal antibodies for Pgp-1, IL-2R, H-2k, CD3, and F23.1 (T cell receptor V beta 8), we characterized the 'radioresistant' CD4-CD8- double negative thymocytes at an early stage after 800 rad irradiation. Most of the CD4-CD8- cells on day 8 after irradiation expressed a high level of Thy-1, H-2k, and PNA, while a small proportion of these cells were CD3+ and/or F23.1+. The appearance of Pgp-1 and IL-2R on the 'radioresistant' double negative precursors was also sequentially examined from day 5 to day 9 after irradiation. The double negative thymocytes at day 5 expressed the highest level of Pgp-1 antigens and these cells gradually decreased in number from day 7 to day 9. By contrast, IL-2R was transiently expressed on the double negative cells on the day 7 and 8 after irradiation. These results indicate that progression of thymocyte development occurred within the CD4-CD8- thymocytes after irradiation. We further examined the homing ability of the double negative 'radioresistant' intrathymic T cell precursors to the periphery by intrathymic cell transplantation method. The double negative thymocytes proliferate and differentiate into CD4+CD8+ cells and CD4+CD8- cells but few CD4-CD8+ cells in the thymus, while only CD4-CD8+ cells were detected in the peripheral lymphoid organs 14 days after intrathymic transplantation of the double negative cells in the H-2 compatible Thy-1 congenic mice. These results suggest that the 'radioresistant' intrathymic precursors differentiate and mature in the thymus and migrate to the periphery.
authors.affiliation: Department of Immunology, Kyushu University, Fukuoka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ayukawa
authors.forename: S
authors.initials: S
authors.lastname: Tomooka
authors.forename: T
authors.initials: T
authors.lastname: Asano
authors.forename: K
authors.initials: K
authors.lastname: Taniguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshikai
authors.forename: K
authors.initials: K
authors.lastname: Nomoto
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D017252:CD3 Complex; D015704:CD4 Antigens / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000502:physiology* / Q000528:radiation effects; D016827:CD8 Antigens; D002454:Cell Differentiation; D005260:Female; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D051379:Mice; D008806:Mice, Inbred AKR; D011836:Radiation Tolerance; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D015375:Receptors, Interleukin-2 / Q000032:analysis; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000502:physiology* / Q000528:radiation effects
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D011948:Receptors, Antigen, T-Cell; D015375:Receptors, Interleukin-2