免疫对辐射损伤小鼠造血重建的影响——(一)辐射损伤小鼠造血重建规律

为了减轻或避免骨髓移植受体发生移植物抗宿主反应(GVHR),深入揭示免疫嵌合体形成机制,我们开展了“辐射损伤小鼠造血重建免疫学影响的研究。本文主要观察了骨髓移植后各类造血细胞重建规律。结果表明,每根股骨骨髓细胞数和每脾细胞数均随照后时间后延而不断增加,二者间呈明显正相关关系;每根股骨内CFU—S、CFU—C、CFU—E含量则随照后时间延长呈指数增加。各类造血细胞重建过程中,CFU—S起步早、增殖速率快、CFU—E、BFU—E后照9天才开始再建。说明致死剂量照射机体仍具有调控造血重建能力,其程序为先促进CFU—S增殖机能,待干细胞池数目抵一定程度时,再增强其分化机能,从而,渐渐恢复正常造血过程。

Effects of immunization on the hemopoietic reconstruction after radiation injury in mice (Ⅰ)Regular patterns of hemopoietic reconstruction after radiation injuries

To study the mechanisms of forming immunochimeras and accelerating the production of immunologic tolerance by lymphocytes differentiated from hemopoietic stem cells which were transplanted into the host in order to relieve or avoid GVHR,we studied the effects of immunization on reconstruction after radiation injury. We first investigated the regular patterns of hemopoietic reconstruction in mice which were exposed to 9.5 Gy y-irradiation and received homologous BMT. The results obtained are:1. After the 2nd day of irradiation the cellularities of BM and spleen were in a low level in comparison to the control group; after the 9th day, however, these parameters increased sharply by a tenfold to those of the control; then the cellularities increased continuously, it became normal approximately by the 30th day. 2 .The contents of CFU-S, CFU-G and CFU-E per 105 BMC also increased with the time linearly; proliferation of CFU-S started earliest and it grew faster than others; by the 23rd day CFU-S reached the peak, after which they decreased gradually. It is suggested that in the early stage of BMT the predominant proliferation is CFU-S, followed by the rapid differentiation and gradually repopulating to normal. 3 .The reconstruction of erythroid hemopoiesis started just by the 9th day after BMT, but its growth rate was apparently faster than that of granulopoiesis.