BIPHASIC PATTERN OF THYMUS REGENERATION AFTER WHOLE-BODY IRRADIATION

• DOI: 10.1084/jem.129.3.445
• Publication Date: 2004-06-23T23:23:31Z
• Authors: Akikazu Takada; Yumiko Takada; Chester C. Huang; Julian L. Ambrus
• Keywords: Mitotic index

Whole-body irradiation of mice with 300 or 400 R causes a precipitous fall in thymus weight, followed by an increase the mitotic index and almost complete restoration mass. This phase is secondary weight gradual recovery. can be prevented intravenous injection bone marrow shielding hind limbs during irradiation. The hypothesis proposed that depends on migration cells from to for maintenance its cell population. Bone chromosome markers injected intravenously into normal lightly irradiated (150 R) animals do not populate host any significant degree. After whole-body heavy doses (400 R), donor dominate marrow. There may competition between dividing which regulates proliferation hemic cells. marker chromosomes repopulate until long after repopulating It possible these have pass through blood-marrow barrier acquire characteristics needed entering thymus. 500 more, first regeneration thymus, represented index, does occur Apparently capable been largely eliminated, organ mass chiefly seeding other sources, probably 200 R, only loss takes place. Probably injury too small interfere supply