白血病小鼠经不同预处理方案的骨髓移植后移植细胞归巢特点

摘要

本研究构建白血病小鼠模型,通过这个模型探讨经不同预处理方案骨髓移植后骨髓细胞的归巢特点.采用非清髓性和放、化疗两种清髓性预处理方案.非清髓性预处理方案为5 Gy60Co γ射线全身照射(A组),放疗清髓性方案为9 Gy 60 Co γ射线全身照射(B组),化疗清髓性预处理方案为大剂量化疗(C组).经上述预处理方案处理的白血病小鼠分别在骨髓移植后24、48、72、96 h检测受鼠外周血、骨髓和脾中有核细胞数和供鼠阳性细胞数,计算供鼠骨髓细胞在受鼠骨髓和脾的归巢率.结果显示:供鼠骨髓细胞在受鼠体内的表现分别为:A组是先归巢再出巢；B组是归巢,出巢,再归巢；C组同B组,但是在脾中的归巢比在骨髓中延迟.比较3组的归巢率显示,供鼠骨髓细胞在骨髓的归巢率在A组早期比B组和C组高,随着时间的推移,部分细胞出巢,归巢率迅速下降至各组中最低,为(0.90±0.09)％(P＜0.05)；B、C两组早期归巢率较低,随着时间推移,细胞出巢后再次归巢,第4天的归巢率迅速上升,B组升至最高,为(2.17±0.26)％(P＜0.05)；在脾中的归巢率与骨髓中相似,C组仍有延迟.结论:经非清髓性预处理的白血病小鼠骨髓移植术后,早期归巢率较高,72 h后明显减低；经放疗清髓性预处理小鼠,其早期归巢率较低,72 h后明显增高；经化疗清髓性预处理小鼠,早期和72 h后归巢率无明显变化,归巢率介于其他两组之间.%The aim of this study was to investigate the homing characteristics of bone marrow cells in leukemia mice after allogenic bone marrow transplantation with different conditioning regimens on the basis of a leukemia mouse model. Allogenic bone marrow transplantation was performed after three different kinds of conditioning regimen, including nonmyeloablative conditioning regimen (5 Gy "Co 7 ray total body irradiation, A group) , radiotherapeutic myeloablative conditioning regimen (9 Gy °° Co 7 ray total body irradiation, B group) and chemotherapeutic myeloablative conditioning regimen (large dose chemotherapy, C group). In the recipient mice, the nucleated cell number in peripheral blood, bone marrow and spleen was counted, the percentage of positive cells capable of connecting with FITC labeled anti-mouse H-2Kb antibody was detected by flow cytometry and the homing ratio in bone marrow and spleen was calculated at 24, 48, 72, 96 h after bone marrow transplantation. The results showed that donor myeloid cells displayed homing and then mobilization (going out of home) in group A; homing, mobilization, and rehoming in group B and C, and there was a little delay of homing in the spleen in group C. In bone marrow, the homing efficiency of A group was the highest in early period and the lowest [ (0. 90 ± 0. 09)% ] in the fourth day with the mobilization of myeloid cells (P <0. 05), and the homing efficiency of B and C groups was lower in the early period and the highest [(2.17±0.26)%, B group ] in the fourth day with the rehoming of myeloid cells (P < 0.05). In spleen, the homing efficiency was similar to that in bone marrow and there still was a little delay in C group. It is concluded that the homing ratio is high in the early period and decrease obviously in 72 h after bone marrow of leukemia mice treated with nonmyeloablative conditioning regimen. The homing ratio is low in the early period and increases obviously in 72 h after bone marrow of leukemia mice treated with radio-or chemotherapeutic myeloablative conditioning regimens. The homing ratio does not obviously change between the early period and 72 h after bone marrow of leukemia mice treated with chemotherapeutic myeloablative conditioning regimen, and lies between group A and B.