The susceptibility of highly purified human CD34+ cells to monocytotropic (Ba-L) and lymphotropic (A018-post) strains of human immunodeficiency virus-1 (HIV-1) was examined. Liquid cultures initiated with fresh immunomagnetically purified CD34+ cells using the K6.1 CD34 monoclonal antibody (MoAb) (K6.1/CD34+) were positive for HIV expression 2 weeks after exposure to HIV-1 Ba-L. These cells wer...

Circulating blood CD34(+) cells consist of hematopoietic stem/progenitor cells, angiogenic cells, and endothelial cells. In addition to their clinical use in hematopoietic stem cell transplantation, CD34(+) cells may also promote therapeutic neovascularization. Therefore, understanding the factors that influence circulating CD34(+) cell frequency has wide implications for vascular biology in ad...

BACKGROUND AND PURPOSE Neonatal hypoxic-ischemic encephalopathy (HIE) is one of the leading causes of neurological handicap in developing countries. Human umbilical cord blood (hUCB) CD34-positive (CD34⁺) stem cells exhibit the potential for neural repair. We tested the hypothesis that hUCB CD34⁺ stem cells and other cell types [leukocytes and nucleated red blood cells (NRBCs)] that are up-regu...

Adult stem cell-based therapy is a promising novel approach for treatment of acute lung injury. Here we investigated the therapeutic potential of freshly isolated human umbilical cord blood CD34(+) progenitor cells (fCB-CD34(+) cells) in a mouse model of acute lung injury. At 3 h post-lipopolysaccharide (LPS) challenge, fCB-CD34(+) cells were transplanted i.v. to mice while CD34(-) cells or PBS...

We used a mouse transplantation model to address the recent controversy about CD34 expression by hematopoietic stem cells. Cells from Ly-5.1 C57BL/6 mice were used as donor cells and Ly-5.2 mice were the recipients. The test cells were transplanted together with compromised marrow cells of Ly-5.2 mice. First, we confirmed that the majority of the stem cells with long-term engraftment capabiliti...

Four-color flow cytometry was used with a cocktail of antibodies to identify and isolate CD34+ hematopoietic progenitors from normal human peripheral blood (PB) and bone marrow (BM). Mature cells that did not contain colony forming cells were resolved from immature cells using antibodies for T lymphocytes (CD3), B lymphocytes (CD20), monocytes (CD14), and granulocytes (CD11b). Immature cells we...

Although the CD34 antigen is widely used in the identification and purification of hemopoietic stem and progenitor cells, its function within hemopoiesis is unknown. We have investigated this issue by ectopically expressing human (hu) CD34 on the surface of murine hemopoietic cells. Forced expression of hu-CD34 in the thymocytes of transgenic mice did not appear to affect the development, matur...

Benzene is an established human carcinogen, producing leukemia, hematotoxicity and perhaps lymphoma. Its carcinogenicity is most likely dependent upon its conversion to phenol and hydroquinone, the latter being oxidized to the highly toxic 1,4-benzoquinone in the bone marrow. Exposure of human lymphocytes and cell lines to hydroquinone has previously been shown to cause various forms of genetic...

BACKGROUND Aberrant myeloid antigen (MA) co-expression and high expression of CD34 antigen on the blasts of acute lymphoblastic leukemia (ALL) patients are independently reported to have a role in pathogenesis and prognosis. This study was conducted to determine whether these two parameters are related. METHODS A total of 204 cases of ALL were included in an analysis of blast immunophenotypic...

The human CD34 surface antigen is selectively expressed on stem/progenitor cells within the hematopoietic system. Because CD34 expression is tightly linked to the immature status of hematopoietic cells, with expression being rapidly lost as hematopoietic cells mature and differentiate, an examination of its regulation may provide important insights into the molecular control of blood cell devel...