Hematopoietic defects in mice lacking the sialomucin CD34

作者：Jill Cheng, Susanne Baumhueter, Grace Cacalano, Karen Carver-Moore, Harold Thibodeaux, R Thomas, HE Broxmeyer, Stephanie Cooper, Nancy L. Hague, MW Moore, LA Lasky · 发表于：Blood · 年份：1996 · DOI：10.1182/blood.v87.2.479.bloodjournal872479 · 被引用次数：240 · 研究领域：Zebrafish Biomedical Research Applications、Hematopoietic Stem Cell Transplantation、Platelet Disorders and Treatments

Although the pluripotent hematopoietic stem cell can only be definitively identified by its ability to reconstitute the various mature blood lineages, a diversity of cell surface antigens have also been specifically recognized on this subset of hematopoietic progenitors. One such stem cell-associated antigen is the sialomucin CD34, a highly O-glycosylated cell surface glycoprotein that has also been shown to be expressed on all vascular endothelial cells throughout murine embryogenesis as well as in the adult. The functional significance of CD34 expression on hematopoietic progenitor cells and developing blood vessels is unknown. To analyze the involvement of CD34 in hematopoiesis, we have produced both embryonic stem (ES) cells and mice that are null for the expression of this mucin. Analysis of yolk saclike hematopoietic development in embryoid bodies derived from CD34-null ES cells showed a significant delay in both erythroid and myeloid differentiation that could be reversed by transfection of the mutant ES cells with CD34 constructs expressing either a complete or truncated cytoplasmic domain. Measurements of colony-forming activity of hematopoietic progenitor cells derived from yolk sacs or fetal livers isolated from CD34-null embryos also showed a decreased number of these precursor cells. In spite of these diminished embryonic hematopoietic progenitor numbers, the CD34-null mice developed normally, and the hematopoietic profile of adult blood appeared typical. However...