The CD34 antigen is expressed by 1% to 4% of human and baboon marrow cells, including virtually all hematopoietic progenitors detectable by in vitro assays. Previous work from our laboratory has shown that CD34+ marrow cells can engraft lethally irradiated baboons. Because the CD34 antigen has not been detected on most solid tumors, positive selection of CD34+ cells may be used to provide marro...

Freshly cultured vascular endothelial cells express the CD34 antigen in a diffuse cell surface pattern with some concentration on microvilli. Expression is downregulated with proliferation in continuous culture and undetectable after nine population doublings but can be maintained by restraining cell proliferation and promoting cell contact. Expression of CD34 at the antigen and mRNA levels on ...

OBJECTIVES Surface CD56 expression on leukemic cells in acute promyelocytic leukemia (APML) is considered an indicator of poorer outcome even in patients receiving conventional treatment. METHODS In the present case, at initial diagnosis, the hallmark phenotype of APML was found (strong CD33 and cytoplasmic MPO expression, absence of HLA-DR expression). RESULTS Both CD34 and CD56 antigen ex...

Human hematopoietic colony-forming cells (CFC) express the CD34 antigen (CD34+) as well as differentiation antigens such as CD33 and HLA-DR. CD34' cells that do not express these latter differentiation antigens have been shown to contain few CFC in direct culture, but generate increasing numbers of CFC when cultured over a marrow stromal cell layer in the long-term culture system. In this study...

CD34 is a leukocyte antigen that is expressed in various cell types including hematopoietic cells. Monoclonal antibodies against human, murine, and canine CD34 proteins have been used for the identification of lymphohematopoietic stem/progenitor cells. The cDNA encoding bovine CD34 was cloned, and its nucleotide sequence was determined. The identity of the deduced amino acid sequence of the enc...

AC133 is one of a new panel of murine hybridoma lines producing monoclonal IgG antibodies (mAbs) to a novel stem cell glycoprotein antigen with a molecular weight of 120 kD. AC133 antigen is selectively expressed on CD34(bright) hematopoietic stem and progenitor cells (progenitors) derived from human fetal liver and bone marrow, and blood. It is not detectable on other blood cells, cultured hum...

The predictive value of HLA-DR and CD34 in the diagnosis of four distinct genetic entities of acute myeloid leukemia (AML) is presently not established. We evaluated the positive and negative predictive values (PPV and NPV, respectively), sensitivity, specificity, and correlation coefficients of HLA-DR and CD34 in AML patients with t(15;17), t(8;21), inv(16), and abn(11q23). In AML with t(15;17...

PURPOSE Kaposiform-hemangioendothelioma (KHE) is a rare vascular tumor,developing predominantly in infants and children. Despite its benign histology, this tumor frequently behaves aggressively,causing significant morbidity and mortality. The striking resemblance of its spindle cell proliferation to that seen in Kaposi Sarcoma (KS) led to the designation of KHE for this rare lesion. This work e...