Mehr R, Fridkis-Hareli M, Abel L, Segel L, Globerson A
Theoretical Division, Los Alamos National Laboratory, NM 87545, USA.
J Theor Biol. 1995 Nov 21;177(2):181-92. doi: 10.1006/jtbi.1995.0237.
Lymphocyte development in irradiated thymuses was analyzed using two complementary strategies: an in vitro experimental model and computer simulations. In the in vitro model, fetal thymus lobes were irradiated and the regeneration of cells that survived irradiation were examined, with the results compared to those of reconstitution of the thymus by donor bone marrow cells and their competition with the thymic resident cells. In vitro measurements of resident cell kinetics showed that cell proliferation is slowed down significantly after a relatively low (10 Gy) irradiation dose. Although the number of thymocytes that survived irradiation remained low for several days post-irradiation, further colonization by donor cells was not possible, unless performed within 6 h after irradiation. These experimental results, coupled with the analysis by computer simulations, suggest that bone marrow cell engraftment in the irradiated thymus may be limited by the presence of radiation-surviving thymic resident cells and the reduced availability of seeding niches.
体外实验模型和计算机模拟。在体外模型中，对胎儿胸腺叶进行辐照，并检查辐照后存活细胞的再生情况，将结果与供体骨髓细胞对胸腺的重建及其与胸腺驻留细胞的竞争情况进行比较。驻留细胞动力学的体外测量表明，相对低剂量（10戈瑞）辐照后，细胞增殖显著减慢。尽管辐照后存活的胸腺细胞数量在辐照后数天内仍保持较低水平，但除非在辐照后6小时内进行，否则供体细胞无法进一步定植。这些实验结果，再加上计算机模拟分析，表明受辐照胸腺中骨髓细胞的植入可能受到辐射存活的胸腺驻留细胞的存在以及植入龛位可用性降低的限制。
