小鼠胚胎AGM区Flk-1^+细胞的造血特性  

Hematopoietic Potential of Flk-1^+ Populations in Mouse Embryonic AGM Region

作　　者：周帆[1,2] 李专[2] 刘兵[1,2] 

机构地区：[1]安徽医科大学解放军307医院临床学院,安徽合肥230032 [2]军事医学科学院附属医院,307-青藤转化医学中心,北京100071

出　　处：《中国实验血液学杂志》2013年第2期446-450,共5页Journal of Experimental Hematology

摘　　要：本研究旨在考察Flk-1分子在胚胎期10.5 d(E10.5)的主动脉-性腺-中肾区(AGM区)不同类型造血前体细胞的表达情况。通过流式细胞术分析发现低于10%的Flk-1+细胞与CD41、CD45/Ter119有共表达,继而分选出CD31+CD45-Ter119-Flk-1+CD41+(R1,代表不成熟的造血前体细胞)和CD31+CD45-Ter119-Flk-1+CD41-(R2,代表内皮细胞)两群细胞,利用造血集落培养和OP9共培养体系分别考察其体外的髓系与淋系潜能。结果表明:仅R1组细胞能在造血集落培养体系中形成典型的造血集落,但与OP9共培养7-9 d后,两组细胞均能产生丰富的造血前体细胞(CD45+c-Kit+)、髓系细胞(Gr-1+/Mac-1+)、红细胞(Ter119+)和B淋巴细胞(CD19+)。结论:E10.5的小鼠胚胎AGM区Flk-1仍然在幼稚的造血前体细胞以及更早期的生血内皮细胞表达,但是此时的造血干细胞前体和造血干细胞是否表达Flk-1仍需通过体内功能实验明确。This study aimed to investigate the expression of Flk-1 on distinct hematopoietic precursor cells in E10.5 mouse AGM region. By flow cytometry, we found that 〈 10% of Flk-1＋ cells of El0.5 AGM region co-expressed CD41 and CD45/Ter119. Then, E10.5 AGM cells were fractionated into two subsets, the CD31 ＋ CD45- Ter119- Flk- 1 ＋ CD41 ＋ cells （R1, putative immature hematopoietic cells） and the CD31 ＋ CD45- Ter119- Flk-1 ＋ CD41 - cells （R2, putative endothelial cells ）, followed by methylcellulose-based CFU-C assay and OP9-based stromal co-culture to examine their myeloid or/and lymphoid potential in vitro. The results showed that only R1 cells could give rise to typical hematopoietic colonies in CFU-C assay. In contrast, after co-cultured with OP9 for 7 - 9 days, both subsets could generate abundant hematopoietic progenitor cells （CD45 ＋ c-Kit＋ ）, myeloid cells （Gr-1＋/Mac-1 ＋）, erythroid cells （Terl19 ＋ ）, and B lymphocytes （CD19 ＋ ）. It is concluded that both maturing CD41 ＋ CD45- hematopoietic percusor cells and hemogenic endothelial cells express Flk-1 in E10.5 AGM region. It requires further functional assay in vivo to clarify whether the hematopoietic stem cells （HSCs） and their precursors retain Flk-I expression at this developmental stage.

关 键 词：主动脉-性腺-中肾区 造血前体细胞 内皮细胞 淋巴细胞 FLK-1 

分 类 号：R322.2[医药卫生—人体解剖和组织胚胎学]