Linked Life Data

3525585

Source:http://linkedlifedata.com/resource/pubmed/id/3525585

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1986-9-16
pubmed:abstractText
High-performance liquid chromatography was performed to separate the various isoforms of estrogen receptor from human breast cancer, based on size (high-performance size-exclusion chromatography) and surface charge (high-performance ion-exchange chromatography) properties. The ability of these isoforms to interact with the monoclonal antibodies was assessed. All isoforms exhibited similar immunodeterminant sites, but when they are bound to [125I]iodoestradiol-17 beta (IE), only 30% binding of the radioactive complex to the immobilized monoclonal antibodies was observed. However, the mass of the receptor recognized by the antibody bead, via the estrogen receptor-enzyme immunoassay (ER-EIA), was always significantly higher. This was true for both fractionated and non-fractionated cytosols, suggesting that non-ligand binding forms, such as precursors and products of the estrogen receptor, were also recognized; or the ligand was only selecting for a particular conformer(s); or the monoclonal antibody on the bead recognized other proteins associated with estrogen receptor. Ion-exchange fractionation of unlabeled receptor showed loss of immunodeterminant sites. However, size-exclusion fractionation did not show this effect. Diethylstilbestrol, a competitor of IE binding, showed marked stability of receptor recognized by ER-EIA during both size-exclusion and ion-exchange chromatography. Limited trypsin treatment of the receptor caused the loss of immunodeterminant sites without altering the ligand binding sites. Thus, proteolysis of estrogen receptors in cytosols of human breast cancer could easily lead to underestimation by ER-EIA. Although the components with immunodeterminant sites recognized by ER-EIA were always eluted with the ligand-binding isoforms of the estrogen receptor, our data suggest that the concentration of the protein having the epitope associated with the monoclonal antibody is unequal to that recognized by the steroid ligand. We conclude that application of ER-EIA to clinical assays of estrogen receptors clearly needs further clarification.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9673
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
359
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
475-87
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Interaction of estrogen receptor isoforms with immobilized monoclonal antibodies.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't