Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1999-5-3
pubmed:abstractText
The flt3 ligand (FL) is a growth factor for primitive hematopoietic cells. Serum levels of FL are inversely related to the number and proliferative capacity of early hematopoietic progenitors. We sought to elucidate the molecular mechanism underlying this regulation. Expression of FL was examined in peripheral blood (PB) and bone marrow (BM) cells under normal steady-state hematopoiesis and during transient BM failure induced by chemoradiotherapy in 16 patients with hematological malignancies. Using anti-FL antibodies in Western analysis, flow cytometry, and confocal microscopy, we detected high levels of preformed FL inside but not on the surface of T lymphocytes in steady-state hematopoiesis. Intracellular FL colocalized with giantin and ERGIC-53, indicating that it is stored within and close to the Golgi apparatus. After chemotherapy-induced hematopoietic failure, FL rapidly translocated to the surface of T lymphocytes and the levels of FL released to serum increased approximately 100-fold. Expression of FL mRNA was enhanced only about sevenfold; a similar, twofold to sixfold increase in mRNA was observed in the thymus and BM of mice with irradiation-induced aplasia. Upregulation of FL mRNA was delayed when compared with the appearance of cell surface-associated and soluble protein isoforms. The described changes in FL expression in response to chemotherapy-induced aplasia were observed in all patients, irrespective of the diagnosis and treatment regimen. Our data demonstrate that mobilization of preformed FL from intracellular stores rather than de novo synthesis is responsible for increased FL levels in BM failure.
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
93
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2595-604
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10194439-Adult, pubmed-meshheading:10194439-Aged, pubmed-meshheading:10194439-Animals, pubmed-meshheading:10194439-Antineoplastic Agents, pubmed-meshheading:10194439-Bone Marrow, pubmed-meshheading:10194439-Bone Marrow Cells, pubmed-meshheading:10194439-Female, pubmed-meshheading:10194439-Gene Expression Regulation, Neoplastic, pubmed-meshheading:10194439-Hematologic Neoplasms, pubmed-meshheading:10194439-Hematopoiesis, pubmed-meshheading:10194439-Humans, pubmed-meshheading:10194439-Male, pubmed-meshheading:10194439-Membrane Proteins, pubmed-meshheading:10194439-Mice, pubmed-meshheading:10194439-Microscopy, Confocal, pubmed-meshheading:10194439-Middle Aged, pubmed-meshheading:10194439-RNA, Messenger, pubmed-meshheading:10194439-T-Lymphocytes, pubmed-meshheading:10194439-Time Factors, pubmed-meshheading:10194439-Transcription, Genetic
pubmed:year
1999
pubmed:articleTitle
Mechanism of flt3 ligand expression in bone marrow failure: translocation from intracellular stores to the surface of T lymphocytes after chemotherapy-induced suppression of hematopoiesis.
pubmed:affiliation
Department of Research, University Hospital Basel, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't