转染TPO基因的骨髓基质细胞移植对放射损伤小鼠造血重建的影响

Influence of transplantation of TPO gene modified bone marrow stromal cells on hematopoietic reconstitution of radiation injured mice

目的通过观察转染TPO基因的BMSCs移植对放射损伤后小鼠在血小板恢复及造血重建方面的作用,探索基质细胞介导的造血生长因子基因治疗促进造血功能重建的可行性。方法用单次剂量6.5Gy的60Co-γ射线照射受体鼠,照射后动物40只随机分四组,单纯骨髓细胞移植组(A组)、未转染BMSCs+骨髓细胞移植组(B组)、转染TPO基因的BMSCs+骨髓细胞移植组(C组)、转染空载体的BMSCs+骨髓细胞移植组(D组),分别于照射后24小时内给予骨髓细胞、BMSCs移植,在不同时相点进行血细胞计数。结果B组、C组、D组WBC最低值较A组高,且WBC的恢复时间提前约7天,同时有一定程度加速PLT的恢复。各组在不同时间的外周血Hb均相近。C组PLT下降程度轻,最低值较A组、B组、D组高,且维持在较高水平。结论骨髓细胞联合BMSCs移植有利于造血快速重建,主要是加速WBC的恢复,而TPO基因疗法主要促进PLT的恢复。

Objective By observing the effect of implantation of BMSCs transfected with TPO genes on platelet recovery and hematopoietic reconstitution, we explore the gene therapy feasibility of hematopoietic growth factor mediated by BMSCs and the effects on promoting hematopoietic reconstitution. Methods The recipient mice were conditioned with 6.5Gy ^60Co-γ rays and divided into four groups randomly. Group A.. bone marrow cells; Group B： bone marrow cells plus untransfected BMSCs; Group C.. bone marrow cells plus BMSCs transfected with TPO gene; Group D.. bone marrow cells plus BMSCs transfected with void vector （pcDNA3.1 expressing plasmid）. The mice in 4 groups were infused with bone marrow cells and BMSCs respectively within 24 hours after irradiation. The blood cells in peripheral blood were counted at different time points after transplantation. Results The minimum peaks of WBC in Groups B, C and D were higher than that of Group A（P〈0. 05）. The recovery of WBC was 7 days earlier as compared to Group A. Meanwhile, there was a trend towards accelerated recovery of PLT（P〈0.05）. Hb levels were decreased continually in Groups A, B and D and the nadirs of Hb in these groups appeared on the 28th day, The minimum peak of Hb in Group C appeared on the 14th day. Subsequently, Hb level recoverd gradually and was obviously higher than that of other groups（P〈0.05）At day 28. The minimum peak of PLT level in Group C was higher than that in other groups （P〈0.05）. In addition, PLT level was sustained. Further, Hb level had a significant increase at the 28th day（P〈0. 05 ）, Conclusion Co-transplantation of bone marrow cells and BMSCs might be helpful for hematopoietic reconstitution, especially it could accelerate the recovery of WBC. However, TPO gene therapy could promote the recovery of PLT.