在小鼠骨髓移植中CCR5与急性移植物抗宿主病的相关性研究

本研究评价供者CCR5在经过强化预处理的骨髓移植动物模型受者体内的作用,为今后的异基因造血干细胞移植的临床应用提供科学依据.经过致死剂量照射的BALB/c小鼠接受异基因C57BL/6小鼠的骨髓移植.根据回输的细胞不同实验分为4组:B6 CCR5 KO组,受者接受C57BL/6 CCR5-/-小鼠骨髓和脾脏细胞;B6 WT组,受者接受野生型C57BL/6小鼠骨髓和脾脏细胞;B6 CCR5 KO BMC组,受者只接受C57BL/6 CCR5-/-小鼠骨髓细胞;B6 WT BMC组,受者只接受野生型C57BL/6小鼠骨髓细胞.结果表明:较之B6 WT组,B6 CCR5 KO组小鼠以更快的速度死于急性GVHD;其受者体内的CD8+T细胞更大量的增殖;其T细胞恢复后产生更多的INF-γ和TNF-α并且由于其T细胞有丝分裂原刀豆素水平处于较高水平,从而进一步促进T细胞的增殖,提示CCR5的作用之一是下调参与排异反应的供者CD8+T细胞的增殖.组织学评价提示,移植剔除CCR5基因受者细胞的小鼠肾脏出现了病理损伤并且肝脏存在有更为严重的病理变化.结论:剔除CCR5基因的异基因骨髓移植使GVHD发病率的增加,供者CD8+T细胞在受者体内增殖增加以及肝肾损害加重,这提示CCR5在异基因骨髓移植中起着重要作用.

Relationship Between CCR5 and Acute Graft-Versus-Host Disease in Murine Bone Marrow Transplantation

This study was aimed to eveluate the role of CCR5 on donor cells in recipient models received intensive conditioning, so as provide the scientific evidence for clinical application of allo-HSCT. Lethally irradiated BALB/cmice received allogeneic bone marrow transplants from C57BL/6 mice. Mice divided into 4 groups according to receiving variant donor cells: B6 CCR5 KO group, receiving C57BL/6 CCR5 -/- mice bone marrow cells and splenocytes; B6 WT BMC group, receiving C57BL/6 mice bone marrow cells and splenocytes; B6 CCR5 KO BMC group, receiving C57BL/6 CCR5 -/ bone marrow cells alone; B6 WT BMC group, receiving C57BL/6 mice bone marrow cells alone.The result showed that compared to B6 WT BMC group, B6 CCR5 KO group succumbed to acute GVHD at an accelerated rate. Donor CD8 + T cells expanded to a significantly greater extent in recipients of CCR5 KO, compared with B6 WT control cells. T cells recovered from recipients of CCR5 KO cells produced more IFN-γ and TNF-α and proliferated to a T-cell at a significantly higher level than T cells from recipients of WT cells, indicating that CCR5 plays a role in downregualting donor alloreative CD8 + T-cells expansion. Histological assessment of the mice indicated pathological le sions in the kidneys and a greater degree of liver pathological changes in mice that received CCR5 KO donor grafts. It is concluded that the knock-out of CCR5 on donor cells results in increase of GVHD and donor CD8 + T cell expansion, as well as hepatic and renal lesions in allo-HSCT, which indicates that CCR5 is very important in allo-BMT.