人脐血细胞在SCID小鼠体内生长特性的研究

本实验将人脐血和骨髓单个核细胞,分别经腹腔输入C.B-17SCID小鼠体内,动态观察了受体内人CD3抗原表达及增殖能力。结果输入脐血或骨髓单个核细胞后,受体内均有逐渐增加的人CD3细胞(分别从2.0％、1.5％增至6.8％、5.4％),且脐血组高于骨髓组。接种后60d,二组实验小鼠骨髓CFU-GM产率明显高于对照组(P<0.01),脐血组高于骨髓组(P<0.05)。在60d时受体小鼠外周血、骨髓、肝、脾、肺组织和骨髓CFU-GM集落,用PCR方法检测出人Y染色体特异DNA片段。结果表明,输注人脐血或骨髓细胞到SCID小鼠腹腔后,可在体内长期生长且具有增殖能力。这种模型的建立为今后造血细胞体内研究提供了一种良好途径,也进一步以动物实验证实脐血造血干/祖细胞具有不同于骨髓造血细胞的生物学特性。

GROWTH CHARACTERISTICS OF HUMAN UMBILICAL CORD BLOOD CELLS IN SCID MICE

In this study, the mononuclear cells of male human umbilical cord blood (HUCB) or bone marrow (BM) were injected intraperitoneally into C.B-17 SCID female mice (6-8 weeks old) and observed kinetically the expression of human CDS antigen and proliferation. The result showed that the percentage of CD3 cells increased gradually after transfered into SCID mice with HUCB or BM hematopoietic cells within two months and there was more number of CFU-GM at the 60th day after injection of HUCB or BM than that of SCID mice injected with normal saline. The human Y-chromosome DNA fragment in recipient mice was confirmed by polymerase chain reaction (PCR) in peripheral blood, bone marrow, liver, spleen, lung and the culture of CFU-GM. These results suggested that HUCB or BM hematopoietic cells could survive and proliferate in xenogeneic recipients. This xenograft model will provide a good method to study hematopoietic stem / progenitor cells of cord blood or bone marrow in vivo, and further confirm characteristics of hematopoietic stem / progenitor cells in HUCB being distinct from BM by animal experiment in vivo.