脐血造血干/祖细胞免疫表型的流式细胞术双标法分析及其意义

目的比较脐血和骨髓中造血干/祖细胞(HSPC)的免疫表型差异.方法使用流式细胞术(FCM)双标法对38份脐血及10份骨髓HSPC进行免疫表型分析.结果①脐血有核细胞中CD34+细胞所占比例与骨髓中相近,约为0.5%;②脐血CD34+细胞中CD34+CD38-[(17.C4±5.37)%]、CD34+HLA-DR-[(32.65±10.71)%]及CD34+H-CAM+(CD44+)[(77.84±7.69)%]亚群含量均高于骨髓[含量分别为(8.26±3.19)%、(14.05±1.67)%和(70.02±6.40)%],CD34+CD13+、CD34+CD19+亚群比例低于骨髓.结论脐血与骨髓CD34+细胞比例相近,但前者较原始的干细胞含量更高,故脐血是极具潜力的HSPC来源;而脐血CD34+细胞中髓系及淋系祖细胞含量低于骨髓,可能是脐血移植后造血及免疫重建缓慢的原因之一.

Analysis of immunophenotype of hematopoietic stem/progenitor cells in human umbilical cord blood with flow cytometry and its significance

OBJECTIVE: To study the difference of immunophenotype of hematopoietic stem/progenitor cells (HSPCs) between human umbilical cord blood(UCB) and bone marrow(BM). METHODS: The expression of CD antigens and cell adhesion molecules on HSPCs in 38 UCB and 10 cases BM were investigated with monoclonal antibodies and double immunofluorescence using flow cytometry. RESULTS: 1. The CD34+ cell population in nucleated cells of UCB was similar to that of BM, being about 0.5%; 2. The frequencies of CD34+CD38-, CD34+HLA-DR- and CD34+H-CAM+ (CD44+) cells in UCB CD34+ cells were higher, while the frequencies of CD34+CD13+ and CD34+CD19+ cells in UCB were lower than that in BM. CONCLUSION: The total number of CD34+ cells in UCB and BM was very similar. However, there was a higher proportion of more primary HSPCs in UCB, which was able to reconstitute hematopoiesis as an potential source of HSPCs, the proportion of relatively mature HSPCs (CD34+ CD19+ and CD34+CD13+) were less in UCB than in BM, which probably accounted for the relatively slow haematopoietic reconstitution following UCB transplantation.