PREVENTION OF GENETIC ANEMIAS IN MICE BY MICRO-INJECTION OF NORMAL HEMATOPOIETIC STEM-CELLS INTO THE FETAL PLACENTA
PREVENTION OF GENETIC ANEMIAS IN MICE BY MICRO-INJECTION OF NORMAL HEMATOPOIETIC STEM-CELLS INTO THE FETAL PLACENTA
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DOI：
10.1073/pnas.76.11.5736
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发表时间：
1979-01-01
影响因子：
11.1
通讯作者：
MINTZ, B
中科院分区：
文献类型：
--
作者：
FLEISCHMAN, RA;MINTZ, B
W基因座突变基因纯合的小鼠有明显的大细胞性贫血，在某些基因类型中是致命的。这种缺陷被认为起源于发育中的多能造血干细胞群体。贫血在妊娠第13天首次出现，此时肝脏是主要的造血器官。已知的纯合子肝脏中造血灶的稀少和红细胞的有限形成表明，这种胎儿--与正常胎儿不同--可能具备在子宫内种植遗传正常的造血组织的条件。如果这是在第13天之前完成的，贫血可能基本上被预防，或者至少显著减轻，并通过细胞选择很快实现正常。事实证明，情况就是这样。于妊娠第11天将同种异体正常胎肝细胞显微注射入胎盘血管内。在分离配子产生的8个突变纯合子中，有6个(4W/W，2WV/WV)成功地植入了供体细胞。菌株特异性Hb标记显示红系血统被正常类型替换，在W/W(通常更严重的贫血)受体中替换的速度更快。菌株特定同工酶的差异表明，白细胞也被替换了。最初的选择压力，即W突变的表型损害，一定发生在多能干细胞阶段。动物对供体细胞保持免疫耐受性，没有发生移植物对宿主的反应。早期引入在基因上不同于动物所有其他组织的造血细胞，为追踪体内正常的造血谱系，分析细胞和组织之间的相互作用，如淋巴细胞和胸腺之间的相互作用，以及澄清其他血液或免疫功能低下或恶性肿瘤的病因提供了可能性。
Mice homozygous for mutant genes at the W locus have a marked macrocytic anemia that is fatal in some genotypes. The defect is believed to originate in the developmentally pluripotent hematopoietic stem cell population. Anemia is first grossly manifest on day 13 of gestation, when the liver is the chief hematopoietic organ. The known paucity of blood-forming foci in livers of homozygotes and the limited formation of their erythrocytes suggested that such fetuses-unlike normal ones-might have conditions favorable for in utero seeding of genetically normal hematopoietic tissue. If this were accomplished before day 13, the anemia might essentially be prevented, or at least substantially mitigated, and normalcy soon achieved by cell selection. This proved to be the case. Allogeneic normal fetal liver cells were microinjected into the blood vessels of the fetal placenta on day 11 of gestation. Of 8 mutant homozygotes born from segregating matings, 6 (4 W/W, 2 Wv/Wv) were successfully populated with donor cells. Strain-specific Hb markers demonstrated replacement of the erythroid lineage with the normal type, the rate of substitution being more rapid in the W/W (ordinarily more anemic) recipients. Strain-specific isozyme differences revealed that white blood cells were also replaced. The initial selective pressure, the W-mutant phenotypic lesion, must have occurred at the pluripotent stem cell stage. The animals remained immunologically tolerant of the donor cells and no graft vs. host reaction occurred. The early introduction of hematopoietic cells differing genetically from all the other tissues of the animal provides possibilities for tracing normal hematopoietic lineages in vivo, for analyzing cell and tissue interactions, such as those between lymphocytes and thymus, and for clarifying the etiology of other blood or immune insufficiencies or malignancies.