In Human Erythroid Massive Amplification (HEMA) cultures, AB mononuclear cells (MNC) generate 1-log more erythroid cells (EBs) than the corresponding CD34(pos) cells, suggesting that MNC may also contain CD34(neg) HPC. To clarify the phenotype of AB HPC which generate EBs in these cultures, flow cytometric profiling for CD34/CD36 expression, followed by isolation and functional characterization...

Objective. Human CD34 2 hematopoietic stem cells (HSCs) have been identified as potential precursors of CD34 1 HSCs by using xenogeneic transplantation systems. However, the properties of CD34 1 cells generated from CD34 2 cells have not been precisely analyzed due to the lack of an in vitro system in which CD34 1 cells are continuously produced from CD34 2 cells. We conducted this study to det...

BACKGROUND AND OBJECTIVES The percentages of CD34+ cells in the bone marrow of patients with acute myeloid leukemia (AML) vary widely. Especially in the low range (<5% CD34+ cells), the nature (normal or malignant) of the CD34+ cells is uncertain. Since only in a minority of cases are molecular techniques applicable, in this study we explored a multiparameter approach using phenotypic and funct...

To clarify whether the expression of the WT1 gene in leukemic cells is aberrant or merely reflects that in normal counterparts, the expression levels of the WT1 gene were quantitated for normal hematopoietic progenitor cells. Bone marrow (BM) and umbilical cord blood (CB) cells were fluorescence-activated cell sorting (FACS)-sorted into CD34+ and CD34- cell populations, and the CD34+ cells into...

The human CD34 hematopoietic stem cell antigen is a highly glycosylated type 1 membrane protein of unknown function. CD34 is expressed on 1% to 4% of bone marrow cells, including pluripotent stem cells and committed progenitors of each hematopoietic lineage. CD34 has also been shown to be expressed on the small vessel endothelium of a variety of tissues and on a subset of bone marrow stromal ce...

All seven of a set of CD34 monoclonal antibodies that recognize epitopes on an approximately 110 Kd glycoprotein on human hemopoietic progenitor cells also bind to vascular endothelium. Capillaries of most tissues are CD34 positive, as are umbilical artery and, to a lesser extent, vein, but the endothelium of most large vessels and the endothelium of placental sinuses are not. Angioblastoma cel...

Peripheral node addressin (PNAd) is a complex mixture of glycoproteins with L-selectin ligand activity that functions in lymphocyte homing. We have investigated the contribution of the sialomucin CD34 relative to other components of PNAd in lymphocyte tethering and rolling in in vitro laminar flow assays. PNAd was isolated with MECA-79 mAb-Sepharose from tonsillar stroma, and the CD34 component...

CD34 is a cell-surface transmembrane protein expressed specifically at the stem/progenitor stage of lymphohematopoietic development that appears to regulate adhesion. To elucidate intracellular signals modified by CD34, we designed and constructed glutathione-S-transferase (GST)- fusion proteins of the intracellular domain of full-length CD34 (GST-CD34i(full)). Precipitation of cell lysates usi...

Key Points • AngiomiR-126 is secreted from circulating CD34 cells and acts as a signaling mechanism of pro-angiogenic effects on endothelial cells, which is impaired in diabetes. Several peripheral blood mononuclear cell (PBMC)–derived cell populations can promote angiogenesis, and differences in CD34 or CD14 surface expression have been used to separate PBMC subpopulations in this respect. Ang...