Functional Analysis Of Tgf-beta Family Signaling During

了解T淋巴细胞在胚胎造血过程中的细胞谱系决定机制，对艾滋病的防治具有重要意义。BMP指定中胚层组织更腹侧的命运。造血细胞来源于最腹侧的中胚层，因此，BMPs被推测在造血组织中T淋巴细胞谱系的特化过程中发挥重要作用。我们证明这一假说的基本策略是用全胚胎培养系统培养BMP或BMP受体基因缺失的胚胎，然后将Cre重组酶表达质粒显微注射到胚胎的感兴趣区域。通过这种方法，我们可以实现区域特异性的基因中断。为此，首先，我们建立了早在5.5天胚胎的胚胎培养方法。我们发现，对于E5.5胚胎，补充有75%大鼠血清的DMEM比100%大鼠血清更有效，而对于E5.75胚胎，100%大鼠血清更有效。我们正在优化条件，以实现Cre质粒的Cre依赖的基因中断。通过本研究所获得的知识将使我们更好地了解原始的和最终的造血。

For prevention and cure of AIDS, it is important to know the mechanism of how cell lineage for T lymphocyte is determined during embryonic hematopoiesis. BMPs specify the fate of mesodermal tissues more ventral. Hematopoietic cells are derived from the most ventral mesoderm, therefore, BMPs are hypothesized to play important roles during specification of T lymphocyte lineage in the hematopoietic tissues. Our basic strategy to prove this hypothesis is to culture embryos that have floxed alleles for BMPs or BMP receptors using whole embryo culture system, and then to microinject Cre recombinase expressing plasmids in the interested region of embryos. Through this method, we could achieve region specific gene disruption. For this purpose, first, we established the culture method for the embryos as early as day 5.5 embryos. We found that DMEM supplemented with 75% rat serum worked better than 100 % rat serum for E5.5 embryos whereas 100 % rat serum works better for E5.75 embryos. We are underway to optimize the condition to achieve the Cre-dependent gene disruption by Cre plasmids. The knowledge that will be acquired through this research may give us better understanding for the primitive and definitive hematopoiesis.