Linked Life Data

1691249

Source:http://linkedlifedata.com/resource/pubmed/id/1691249

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1990-5-21
pubmed:abstractText
Highly purified erythroid burst-forming units (BFU-e) from human embryonic liver, adult marrow and blood were manipulated in vitro by cytokine addition in order to explore their requirements for c-myb function and potential for fetal hemoglobin (HbF) synthesis, particularly as related to their cycling activity. c-myb is expressed at a minimal level and functionally required to a limited extent in quiescent adult BFU-e. However, c-myb is actively transcribed and stringently required for differentiation of actively cycling progenitors (embryonic BFU-e, embryonic and adult erythroid colony-forming units). The cycling activity of highly purified adult BFU-e, gradually enhanced by interleukin 3 (IL-3) addition, is strictly and directly related to both their functional requirements for c-myb and the level of myb mRNA expression in the progenitor population. It may be concluded that the transcriptional activity and the functional role of c-myb in early erythropoiesis are dependent upon the cycling activity of the erythroid progenitors. The reactivation of HbF synthesis in normal adult bursts, observed in the standard fetal calf serum-rich (FCS+) clonogenic system, is suppressed in cultures with a drastically limited growth of accessory cells (i.e., in FCS- or FCS+ Mo- conditions). In these cultures, addition of granulocyte/macrophage colony-stimulating factor (GM-CSF) or IL-3 induces a dose-related rise of gamma-chain synthesis, at least in part via a direct action at the BFU-e level. Preliminary studies involving priming of adult BFU-e with IL-3 in liquid phase suggest that the HbF potential is relatively low in quiescent BFU-e, but distinctly higher in actively cycling ones. It is postulated that the in vivo reactivation of HbF synthesis in bone marrow regeneration may be mediated via increased IL-3 and GM-CSF activity, leading to enhanced cycling and differentiation of BFU-e.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0737-1454
pubmed:author
pubmed:issnType
Print
pubmed:volume
8 Suppl 1
pubmed:owner
NLM
pubmed:authorsComplete
N
pubmed:pagination
314-34
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Molecular mechanisms underlying erythropoiesis: cycling activity of adult BFU-e relates to their requirement for c-myb function and potential for HbF synthesis.
pubmed:affiliation
Department of Hematology-Oncology, Istituto Superiore di Santià, Rome, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't