Linked Life Data

3947682

Source:http://linkedlifedata.com/resource/pubmed/id/3947682

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1986-4-11
pubmed:abstractText
Several reports have suggested that variations of albumin concentration in the incubation medium can modulate the magnitude of transferrin binding to the cells. We have investigated this problem further using K562 cells. In the absence of human serum albumin, transferrin binding demonstrated a non-saturable curve which, upon Scatchard analysis, showed two components with high and low affinities. In the presence of 0.5% human serum albumin, the low-affinity but not the high-affinity component was totally inhibited and, thus, the binding showed a saturation plateau at transferrin concentration of 6 micrograms/ml. Increasing concentrations of human serum albumin in the incubation medium led to progressive inhibition of transferrin binding, reaching a plateau at 0.2% human serum albumin. At this concentration transferrin binding was about 12 ng/10(6) cells, corresponding to the saturation plateau for high-affinity binding. Low-affinity transferrin binding in the absence of human serum albumin could readily be displaced by subsequent addition of albumin. Similar inhibition was obtained by another serum protein, ceruloplasmin, suggesting that this inhibition is not unique to albumin and may be a common property of all proteins. Incubation at 37 degrees C with 59Fe-labeled transferrin indicated that all iron uptake occurs through high-affinity binding. We conclude that the reported variations in magnitude of transferrin binding by the cell due to variations in albumin concentration are the result of inhibition of low-affinity binding of transferrin by albumin.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
885
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
294-300
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Albumin inhibition of transferrin low-affinity binding to K562 cells.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.