Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-3-11
pubmed:abstractText
Despite numerous studies investigating the action of c-mpl ligand, no reports have defined the in vivo changes in megakaryocytopoiesis in response to a single injection of this cytokine. Here we compare the kinetics of the megakaryocytopoietic response in C57BI/6J mice administered 25 micrograms/ kg or 250 micrograms/kg of pegylated (PEG) murine megakaryocyte growth and development factor (MGDF) as a single intravenous injection. Megakaryocytes of mice treated with MGDF had normal ultrastructure, showing a typical distribution of the demarcation membrane system, alpha-granules, and other cytoplasmic organelles. Megakaryocyte ploidy, size, and frequency were markedly increased with both MGDF doses. Megakaryocyte ploidy was maximally increased from a modal value of 16N to 64N on day 3, with both doses of MGDF. Similarly, a comparable increase in megakaryocyte size occurred in the two MGDF groups. Increased megakaryocyte size was coupled to the increase in megakaryocyte ploidy, and no evidence for independent regulation of megakaryocyte size within individual ploidy classes was apparent. In contrast to megakaryocyte ploidy and size, the increase in megakaryocyte frequency was markedly different with the two doses of MGDF. The proportion of 2N and 4N cells was increased from a baseline of 0.035% to 0.430% by day 4 in mice treated with the higher dose of MGDF, but only to 0.175% in mice administered 25 micrograms/kg of MGDF. The marked increase in the pool of these immature megakaryocytes translated to a sustained elevation in the frequency of polyploid megakaryocytes (8N cells and greater). In contrast to the sustained increase in the frequency of polyploid cells, the level of polyploidization was downregulated on days 6 to 10, but normalized by day 14. We conclude that a single injection of MGDF is able to expand the megakaryocytic pool in a dose-dependent manner, which, with subsequent maturation, should lead to an increased rate of platelet production.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
823-33
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
A single injection of pegylated murine megakaryocyte growth and development factor (MGDF) into mice is sufficient to produce a profound stimulation of megakaryocyte frequency, size, and ploidization.
pubmed:affiliation
Division of Experimental Hematology, St Jude Children's Research Hospital, Memphis, TN 38105, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't