CFU-S的不均一性与放射损伤效应的研究

正常(NBM)与3Gy照射(IBM)骨髓细胞形成的7～13天脾结节数量变化过程不同。NBM组: 7～9天脾结节数呈指数性增加I 9～11天呈指数性下降;11～13天再次增加。IBM组: 7～9天脾结节数增加幅度加大, 但9天后脾结节数无明显改变。NBM组：8天脾结节以红系为主, 13天脾结节以混合型为主。IBM组。8天脾结节中, 红系较对照组明显下降, 13天时与对照无明显差别。 8天CFU-S的放射敏感性高于13天CFU-S, D0值分别为1.09和1.48Gy。在8Gy全身照射后, 小鼠骨髓中8天和13天CFU-S的恢复过程大致相似。本文的实验结果表明, CFU-S的放射敏感性也是不均一的。在7～9天的CFU-S中, 可能存在一个趋向红系分化而对射线更敏感的亚群。

Studies on the heterogeneity and radiosen-sitivity of CFU-S

Mice irradiated with 8.5 Gy were in-jected with bone marrow cells obtained from normal(NBM) or 3 Gy irradiated (IBM)donors.At various intervals(7-13 days)after injection, groups of mice were killed and spleen colohies were count-ed.It was found that the colonies increas-ed in ntmabcr exponentially from days 7 to 9, decreased from days 9 to 11 and increased again from days 11 tol3 in NBM group.In IBM group, the increase of colonies from days 7 to 9 was more pronounced than that of NBM, but no apparent difference was observed from dags 9 to 1 3.The morpholo-gical analysis showed that 50%of d 8 colonies was erythrOpOietic type in NBM, only 27.7% in IBM, d 13 colonies were predominantly mixed type both in NBM (57.7%)and IBM(50.7%).Further stud-ies demonstrated that the radiosensitivity of d 8 CFU-S was significantly higher than that of d 13 CFU-S with D₀ values of 1.48 and 1.09 Gy respectively.The pattern of recovery of d 8 CFU-S in the bone marrow of mice following 3 Gy total body irradiation was similar to that of d 13 CFU-S. All these results indicate that CFU-S is a heterogenous population, and it is supposed that there probably exists a highly radio-sensitive subpopulation in d 7-9 CFU-S with commitment to erythropOietic lineage.