Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
8
|
pubmed:dateCreated |
1998-5-12
|
pubmed:abstractText |
Platelet factor 4 (PF4) has been recognized as an inhibitor of myeloid progenitors. However, the mechanism of action of this chemokine remains poorly understood. The present study was designed to determine its structure/function relationship. A series of peptides overlapping the C-terminal and central regions of PF4 were analyzed in vitro for their action on murine hematopoietic progenitor growth to assess the minimal sequence length required for activity. The peptides p17-58 and p34-58 possessed an increased hematopoietic inhibitory activity when compared with PF4, whereas the shorter peptides p47-58 and p47-70 were equivalent to the native molecule and the peptide p58-70 was inactive. The PF4 functional motif DLQ located in 54-56 was required for the activity of these peptides. The peptide p34-58 impaired to a similar extent the growth of colony-forming unit-megakaryocyte (CFU-MK) as well as burst-forming unit-erythroid (BFU-E) and colony-forming unit-granulocyte-macrophage (CFU-GM), whereas PF4 was more active on CFU-MK. In the experiments using purified murine CD34(+) marrow cells, statistically significant inhibition induced by p34-58 was shown at concentrations of 2.2 nmol/L or greater for progenitors of the three lineages, whereas that induced by PF4 was seen at 130 nmol/L for CFU-MK and 650 nmol/L for CFU-GM and BFU-E, indicating that the p34-58 acts directly on hematopoietic progenitors and its activity is approximately 60- to 300-fold higher than PF4. The p34-58, unlike PF4, lacked affinity for heparin and its inhibitory activity could not be abrogated by the addition of heparin. In addition, an antibody recognizing p34-58 neutralized the activity of p34-58 but not whole PF4 molecule. These results demonstrate that PF4 contains a functional domain in its central region, which is independent of the heparin binding properties, and provide evidence for a model of heparin-dependent and independent pathways of PF4 in inhibiting hematopoiesis.
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
AIM
|
pubmed:chemical | |
pubmed:status |
MEDLINE
|
pubmed:month |
Apr
|
pubmed:issn |
0006-4971
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
15
|
pubmed:volume |
91
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
2772-80
|
pubmed:dateRevised |
2006-11-15
|
pubmed:meshHeading |
pubmed-meshheading:9531587-Amino Acid Sequence,
pubmed-meshheading:9531587-Animals,
pubmed-meshheading:9531587-Cells, Cultured,
pubmed-meshheading:9531587-Coagulants,
pubmed-meshheading:9531587-Hematopoiesis,
pubmed-meshheading:9531587-Mice,
pubmed-meshheading:9531587-Mice, Inbred BALB C,
pubmed-meshheading:9531587-Molecular Sequence Data,
pubmed-meshheading:9531587-Peptides,
pubmed-meshheading:9531587-Platelet Factor 4,
pubmed-meshheading:9531587-Structure-Activity Relationship
|
pubmed:year |
1998
|
pubmed:articleTitle |
New insights into the negative regulation of hematopoiesis by chemokine platelet factor 4 and related peptides.
|
pubmed:affiliation |
Institut des Vaisseaux et du Sang, Hôpital Lariboisière, Paris, France.
|
pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|