These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Mouse yolk sac and intraembryonic tissues produce factors able to elicit differentiation of erythroid burst-forming units and colony-forming units, respectively.
    Author: Labastie MC, Thiery JP, Le Douarin NM.
    Journal: Proc Natl Acad Sci U S A; 1984 Mar; 81(5):1453-6. PubMed ID: 6584891.
    Abstract:
    This work was aimed at elucidating the environmental conditions that account for the production of embryonic erythrocytes in the mouse yolk sac (YS), while the adult-type hemoglobin and erythrocytes are generated in the fetal liver. Differentiation of YS hemopoietic stem cells (YS-HSC) of 9.5-day mouse embryos (prior to the colonization of the liver rudiment by HSC) was investigated in vitro. The influence of well-characterized erythroid growth factors, burst-promoting activity (BPA) and erythropoietin (EPO), which trigger the differentiation of early erythroid burst-forming units (BFU-E) and late erythroid colony-forming units (CFU-E), respectively, was tested on the YS-HSC in two different systems of culture: (i) organ culture and (ii) clonal culture in methylcellulose. When studied in organ culture, where the YS microenvironment was maintained, YS-HSC required only additional EPO to attain complete maturation into adult erythrocytes within 7 days. In contrast, YS hemopoietic single cells grown in methylcellulose, and thus released from the influence of the YS, required the presence of both BPA and EPO to generate BFU-E-derived colonies synthesizing high concentrations of hemoglobin. It is concluded that 9.5-day YS from mouse embryos is by itself able to promote the first differentiation steps of the adult lineage YS-HSC due to an intrinsic production of a BPA-like activity. In contrast, these experiments demonstrate that EPO or an EPO-like activity is not produced by YS tissues. As demonstrated earlier, if embryonic tissue is added to YS organ culture, although separated from it by a filter preventing cell contact, YS-HSC differentiate into adult erythrocytes producing adult-type hemoglobins. This shows that, in contrast to YS tissues, the early embryo produces EPO or a factor that can substitute for EPO.
    [Abstract] [Full Text] [Related] [New Search]