Linked Life Data

6542017

Source:http://linkedlifedata.com/resource/pubmed/id/6542017

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1985-1-14
pubmed:abstractText
Cultured human alveolar macrophages (HAM phi) were found to produce soluble factors which inhibit tritiated thymidine [( 3H]-TdR) incorporation into tumour cells in vitro. We present evidence that thymidine (TdR) can be detected in HAM phi culture supernatants by thin-layer chromatography. Moreover, TdR secretion by HAM phi is an active process. Using [6-14C]-orotic acid as an early precursor to TdR and [3H]-TMP as the phosphorylation product, we were able to show that cultured HAM phi transformed them into labelled TdR. The very efficient thin-layer chromatography of the labelled metabolites was backed up by high-pressure liquid chromatography of nucleotides. HAM phi produce TdR by de novo synthesis and dephosphorylation. This phenomenon is due to the lack of thymidine kinase in normal mature macrophages. Since TdR, in high concentrations, can inhibit DNA synthesis through the 'TdR blockade' phenomenon, it is suggested that TdR secretion by HAM phi is a mechanism of non-specific modulation of tumour cell growth but highly restricted to the immediate macrophage microenvironment in vivo. The effectiveness of the thymidine gradient may thus be quite narrow, but is worthy of interest.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0277-5379
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1543-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Production of the effector molecule thymidine by human lung alveolar macrophages.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't