同种异基因脐血移植小鼠模型的建立

Establishment of a Murine Model for Allogeneic Umbilical Cord Blood Transplantation

探讨胎鼠及新生鼠外周血 (FNPB)移植特性 ,建立同种异基因脐血移植小鼠模型。采用体外集落培养和流式细胞术的方法 ,检测FNPB与骨髓 (BM )造血干 /祖细胞含量与特性。给致死量环磷酰胺预处理的BALB/c(H 2 d)小鼠经尾静脉输注C57BL/ 6(H 2 b)小鼠FNPB ,移植后动态观察受鼠存活状况、植入水平、造血与免疫功能恢复及移植物抗宿主病 (GVHD)发生情况。结果显示 :FNPB中早期红系祖细胞 (BFU E)和CD34+ 细胞含量与BM相近 ,粒单系祖细胞 (CFU GM) (1 4天 ) ,多向祖细胞 (CFU GEMM )及Sca 1 + CD34+ 细胞亚群明显高于BM。FNPB移植能明显提高受鼠存活率 ,重建部分造血与免疫功能 ,未见明显GVHD表现 ,并在受体术后 2 1天骨髓检出供体源造血干细胞占 2 7.94%。结论 :FNPB富含造血干 /祖细胞 。

This study was undertaken to establish a murine model for unrelated allogeneic umbilical cord blood transplantation (UCBT). The characteristics and percentage of hematopoietic stem/progenitor cells between near term fetal and neonatal murine peripheral blood (FNPB) and bone marrow (BM) were evaluated by flow cytometry and semisolid methylcellulose culture. BABL/c(H 2 d)recipient mice conditioned with high dose CTX were transplanted with FNPB form C57BL/6(H 2 b)mice and the survival rate, hematopoietic and immunological reconstruction, graft versus host disease (GVHD) and engraftment level were observed. The results showed that the numbers of day 14 CFU GM and CFU GEMM in FNPB [(176.40±78.39)% and (141.40±56.57)%, respectively] were much higher than those in BM [(75.20±26.41)% and (68.80±23.95)%, respectively]. Moreover the percentage of Sca 1 +CD34 + cell subsets in FNPB (3.63±1.13)% was also higher than that in BM (1.41±0.87)%. FNPB transplantation improved survival rate and reconstituted hematopoietic and immune function in recipients. There was no evidence of GVHD. Chimeric analysis showed the proportion of donor cells in BM of recipients were 27.94% at 21 days after transplantation. It was concluded that FNPB contains more hematopoietic stem and progenitor cells with high expansion ability and weak allogenic immunity which is similar to human UCB. The murine model for allogeneic UCBT (C57BL/6→BALB/c) was established successfully.