全反式维甲酸对脐血红系祖细胞Hoxb2、Hoxb4基因表达的影响

Effect of ATRA on the Expression of Genes Hoxb2 and Hoxb4 in Cord Blood Erythroid Progenitors

本研究探讨全反式维甲酸(ATRA)对人脐血造血干细胞向红系定向增殖分化过程进行干预后hoxb2、hoxb4基因表达的影响。取12例正常足月顺产新生儿断脐后的胎盘段脐血,采用造血干细胞体外培养技术及FQ-RT-PCR方法,以6×10-8mol/L的ATRA干预人脐血造血干细胞向红系定向增殖分化的过程,进而检测空白对照组、ATRA组在培养的第3天、第7天和第10天红系祖细胞hoxb2、hoxb4基因表达情况。结果表明:本实验各组的hoxb2、hoxb4基因在第3天时开始少量表达,在第7天表达明显升高,而在第10天表达最强烈。在空白对照组中,第3天、第7天、第10天hoxb4基因相对表达量较hoxb2高。与空白对照组相比较,ATRA组Hoxb2、Hoxb4基因表达量明显增加。结论:hoxb2、hoxb4基因在脐血HSC向红系定向增殖分化过程中(体外)均有表达,说明hoxb2、hoxb4均与红系造血有相关性,且与hoxb2相比,可能hoxb4与红系造血相关性较大;6×10-8mol/L的ATRA能显著上调正常红系祖细胞hoxb2、hoxb4基因的表达。

This study was aimed to investigate the expressions of genes hoxb2 and hoxb4 after interference of the proliferation and differentiation of hematopoietic stem cells （ HSC ） to the erythroid progenitors （CFU-E） in vitro by using all-trans retinoic acid （ATRA）. The cord blood was collected from 12 cases of fetal placenta umbilical vein and cultured by using culture technique of HSC in vitro. The proliferation and differentiation of HSC to CFU-E were interfered with 6 × 10-8mol/L of ATRA. The expression levels of genes hoxb2 and hoxb4 in blank control and ATRA groups were detected by FQ-RT-PCR on day 3, 7 and 10 of culture. The results showed that the expressions of genes Hoxb2 and hoxb4 were a little on day 3, obviously increased on day 7 and reached highest level on day 10 in 2 groups. The expression level of hoxb4 on day 3, 7 and 10 in blank control group was obviously higher than expression level of hoxb2. As compared with blank control group, the expressions of genes hoxb2 and hoxb4 in the ATRA group were significantly up-regulated. It is concluded that the genes hoxb2 and hoxb4 all expressed in process of proliferation and differentiation to erythroid progenitors, which suggests that hoxb2 and hoxb4 relate to erythroid hematopoesis, and the hoxb4 has more great relevance to erythroid hematopoiesis as compared with hoxb2. The ATRA （6 × 10-8mol/L） can up-regulate the expression of hoxb2 and hoxb4 significantly.