Cell proliferation and thymocyte subset reconstitution in sublethally irradiated mice: Compared kinetics of endogenous and intrathymically transferred progenitors

Journal Article · Sat Jul 01 04:00:00 EDT 1989 · Proc. Natl. Acad. Sci. USA; (United States)

DOI:https://doi.org/10.1073/pnas.86.14.5547· OSTI ID:5696612

Penit, C; Ezine, S

After sublethal (6 Gy) whole-body irradiation, the C57BL/Ba (Thy-1.1) murine thymus regenerated in two waves, on days 3-10 and 25-32, separated by a severe relapse. The second phase of depletion-reconstitution reproduced the first one, in a less synchronous manner. The depletion affected all cell subsets, but CD4+ CD8- cells decreased later than immature cells. Cell proliferation, measured by BrdUrd incorporation, started on day 3 after irradiation and concerned CD4- CD8-, CD4- CD8+, and CD4+ CD8+ cells, sequentially. CD4+ CD8- cells never represented a significant percentage of cycling cells. When irradiation was immediately followed by an intrathymic injection of 10(5) C57BL/Ka (Thy-1.2) bone marrow cells, the relapse in thymus reconstitution was no longer observed. Detected with anti-Thy-1.2 antibodies, donor cells started cycling on day 14 and showed only one wave of proliferation. In these chimeras, recipient thymocytes behave exactly like thymocytes of solely irradiated mice. Intrathymically transferred CD4- CD8- thymocytes 10(5) showed the same proliferation kinetics as endogenous cells, with a peak in number on day 10 but completely disappeared from the thymus on days 14-21. These data reflect maturational differences between intrathymic and bone marrow precursor cells and suggest different radiosensitivities not linked to proliferative status. The resting state of the thymus immigrants was shown by the absence of Thy-1 acquisition by bone marrow cells continuously labeled for 10 days with BrdUrd in vivo before intrathymic transfer. When such labeled bone marrow cells were injected in the thymus, only the minor BrdUrd- subset gave rise to Thy-1+ cells.

• Research Organization: Institut National de la Sante et de la Recherche Medicale Unite 25, Paris (France)
• OSTI ID: 5696612
• Journal Information: Proc. Natl. Acad. Sci. USA; (United States), Journal Name: Proc. Natl. Acad. Sci. USA; (United States) Vol. 86:14; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

560152* -- Radiation Effects on Animals-- Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANIMALS
ANTIGENS
ANTIMETABOLITES
AZINES
BIOLOGICAL MATERIALS
BIOLOGICAL RECOVERY
BLOOD
BLOOD CELLS
BODY
BODY FLUIDS
BONE MARROW CELLS
BROMOURACILS
BUDR
CELL PROLIFERATION
CHIMERAS
CONNECTIVE TISSUE CELLS
DNA REPLICATION
DRUGS
EXTERNAL IRRADIATION
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
IRRADIATION
LEUKOCYTES
LYMPHATIC SYSTEM
LYMPHOCYTES
MAMMALS
MATERIALS
MICE
MOSAICISM
NUCLEIC ACID REPLICATION
NUCLEOSIDES
NUCLEOTIDES
ORGANIC BROMINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PYRIMIDINES
RADIATION CHIMERAS
RADIOSENSITIVITY
RECOVERY
RIBOSIDES
RODENTS
SOMATIC CELLS
SPECIFICITY
SUBLETHAL IRRADIATION
THYMOCYTES
THYMUS
URACILS
VERTEBRATES
WHOLE-BODY IRRADIATION