Linked Life Data

8816953

Source:http://linkedlifedata.com/resource/pubmed/id/8816953

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1996-10-21
pubmed:abstractText
Previously, we have developed a colloidal dextran-stabilized monocrystalline iron oxide nanocompound (MION-46) as a magnetic label for magnetic resonance imaging (MRI). In an effort to use this magnetic label to visualize pancreatic receptor function by MRI in vivo, we investigated the potential of secretin as a vector molecule. Secretin receptors, abundant on exocrine pancreas cells, recognize secretin through its amidated carboxyl terminal. In order to conjugate secretin to MION, we utilized the specific interaction between biotin and streptavidin, since direct conjugation of human secretin to MION has previously resulted in low yields and low affinity of the conjugate (unpublished results). Initially, we biotinylated the N-terminal primary amino group of secretin (60% yield). In a separate step, streptavidin (SA) was immobilized onto the surface dextran molecules of MION (79% yield) by reductive amination. Each secretin molecule was conjugated to one biotin molecule and each MION particle to an average of two SA molecules. The biotinylated secretin was then conjugated to MION through the biotin-streptavidin interaction (90% yield). The secretin-biotin-streptavidin-MION construct thus contained approximately two secretin molecules per MION. An in vitro competitive binding assay of pancreatic acinar cells demonstrated that the magnetically labeled secretin retained affinity to the secretin receptors. In vivo distribution studies in rats showed a significantly higher pancreatic accumulation of the secretin-biotin-streptavidin-MION construct as compared to the control group that had received unmodified MION. Our data indicate that bioactive peptides can be attached to dextran-coated iron oxide particles through the biotin-streptavidin interaction while retaining receptor affinity. Such target-specific agents have potential use in MR imaging to probe for a variety of receptor systems.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1043-1802
pubmed:author
pubmed:issnType
Print
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
311-6
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:8816953-Animals, pubmed-meshheading:8816953-Bacterial Proteins, pubmed-meshheading:8816953-Binding, Competitive, pubmed-meshheading:8816953-Biotin, pubmed-meshheading:8816953-Cells, Cultured, pubmed-meshheading:8816953-Chromatography, High Pressure Liquid, pubmed-meshheading:8816953-Contrast Media, pubmed-meshheading:8816953-Dextrans, pubmed-meshheading:8816953-Ferumoxytol, pubmed-meshheading:8816953-Humans, pubmed-meshheading:8816953-Iodine Radioisotopes, pubmed-meshheading:8816953-Iron, pubmed-meshheading:8816953-Isotope Labeling, pubmed-meshheading:8816953-Magnetic Resonance Imaging, pubmed-meshheading:8816953-Magnetic Resonance Spectroscopy, pubmed-meshheading:8816953-Male, pubmed-meshheading:8816953-Oxides, pubmed-meshheading:8816953-Pancreas, pubmed-meshheading:8816953-Protein Structure, Tertiary, pubmed-meshheading:8816953-Rats, pubmed-meshheading:8816953-Rats, Sprague-Dawley, pubmed-meshheading:8816953-Secretin, pubmed-meshheading:8816953-Streptavidin, pubmed-meshheading:8816953-Tissue Distribution
pubmed:articleTitle
Magnetically labeled secretin retains receptor affinity to pancreas acinar cells.
pubmed:affiliation
Department of Radiology, Massachusetts General Hospital, Boston 02114, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.