BLOOD CYTOKINES FOR IN UTERO BONE MARROW TRANSPLANTATION

人类骨髓可以移植到羊胎儿时， 在子宫里 绵羊出生后，人类造血干细胞 在淋巴样红细胞中产生分化的人血细胞， 骨髓谱系至少两年。 因此羊人嵌合体是 人干细胞移植的重要临床模型。 缺乏重组羊生长因子是一个主要限制， 优化人类细胞在绵羊移植中的生长。 人愿意 通过实验控制促红细胞生成素（Epo）的血液水平， 控制红细胞增殖和分化，然而， 大量的纯绵羊Epo不能用于注射。 容易获得的重组绵羊Epo将显著有助于 造血重建研究在这个有价值的移植模型。 由于我们小组在分子遗传学方面有相当丰富的经验， Epo及其受体，我们建议测试克隆绵羊的可行性 Epo序列;获得绵羊Epo基因的基因组克隆和部分 测序用于cDNA克隆;鉴定表达高水平 Epo mRNA（胎儿肝脏和肾脏，成人贫血肾脏）;并产生 用于PCR或表达文库克隆的cDNA。

Human bone marrow can be transplanted into sheep fetuses when administered in utero. Upon birth of the sheep, the human hematopoietic stem cells produce differentiated human blood cells in the lymphoid erythroid and myeloid lineages for at least two years. Thus the sheep human chimera is an important clinical model for human stem cell (Hsc) transplantation. The lack of recombinant sheep growth factors poses a major limitation to optimizing the growth of human cells in sheep transplants. One would like to manipulate blood levels of erythropoietin (Epo) to experimentally control red blood cell proliferation and differentiation, however, substantial quantities of pure sheep Epo are not available for injection. Readily available recombinant sheep Epo would contribute significantly to hemopoietic reconstitution studies in this valuable transplantation model. Since our group has considerable experience with the molecular genetics of Epo and its receptor, we propose to test the feasibility of cloning sheep Epo sequences; obtaining a genomic clone of the sheep Epo gene and partial sequenced for cDNA cloning; identifying tissues expressing high levels of Epo mRNA (fetal liver and kidney, adult anemic kidney); and generating cDNA for PCR or expression-library cloning.