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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
9
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pubmed:dateCreated |
1992-10-2
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pubmed:abstractText |
We previously showed that the sialoglycoprotein, CD34, which is expressed on primitive human hematopoietic progenitor cells, is cleaved by a unique glycoprotease from Pasteurella haemolytica (P.h. glycoprotease). This proteolytic enzyme specifically cleaves glycoproteins rich in O-sialoglycans. Glycoproteins containing only N-linked glycans are not cleaved. Cleavage of the CD34 antigen results in the loss of epitopes detected by five of seven CD34-designated antibodies. In this study, we investigated the role of the P.h. glycoprotease in isolating CD34+ cells from unfractionated normal human bone marrow mononuclear cells (MNCs), and determined the effect of the glycoprotease on the proliferative capacity of the progenitor-enriched fraction. CD34+ cells were isolated from MNCs using immunomagnetic beads attached via a CD34 antibody whose epitope is susceptible to removal by the cleavage with the glycoprotease. Subsequent cleavage with P.h. glycoprotease for 30 min at 37 degrees C released the CD34+ cells from the beads with a recovery of up to 78%. Using a CD34 antibody whose epitope was not removed by the glycoprotease, up to 95% of the recovered cells expressed CD34. Compared to unseparated MNCs, the CD34+ cells showed the following enrichment of committed hematopoietic progenitors, as assayed in semi-solid media: CFU-GM, 45-fold; CFU-M, 13-fold; BFU-E, 26-fold and CFU-GEMM, 81-fold. Hematopoiesis was also studied in two-stage long-term bone marrow cultures in which the CD34+ cells were co-cultured over irradiated, allogeneic adherent layers. Output of CFU-GM over a seven week period from these cultures was similar to that from control cultures with autologous adherent-cell-depleted marrow MNCs. These data suggest that the loss of O-sialo-glycosylated peptide moieties from P.h. glycoprotease-released CD34+ cells neither affects the functional capacity of committed progenitors, nor impairs the proliferation of long-term culture-generating cells. The P.h. glycoprotease can be used to facilitate the isolation and recovery of functionally competent CD34+ cells at high yield and purity, without prior removal of other adherent cells. The ability to rapidly purify CD34+ cells using this non-cytotoxic enzyme has important implications for bone marrow transplantation as well as for gene transfer studies in vitro.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Sep
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pubmed:issn |
0887-6924
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
6
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
926-34
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1381456-Antigens, CD,
pubmed-meshheading:1381456-Antigens, CD34,
pubmed-meshheading:1381456-Bone Marrow Cells,
pubmed-meshheading:1381456-Cell Division,
pubmed-meshheading:1381456-Cell Separation,
pubmed-meshheading:1381456-Cells, Cultured,
pubmed-meshheading:1381456-Colony-Forming Units Assay,
pubmed-meshheading:1381456-Hematopoietic Stem Cells,
pubmed-meshheading:1381456-Humans,
pubmed-meshheading:1381456-Leukocytes, Mononuclear,
pubmed-meshheading:1381456-Metalloendopeptidases
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pubmed:year |
1992
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pubmed:articleTitle |
Retention of progenitor cell function in CD34+ cells purified using a novel O-sialoglycoprotease.
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pubmed:affiliation |
Oncology Research Laboratories, Toronto Hospital, Ontario, Canada.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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