Lipoprotein binding of crosslinked type III collagen aminopropeptide and fractions of its antigen in blood.
When [125I] labelled bovine type III collagen aminopropeptide (PIIIP) is incubated with tissue transglutaminase (TGase) mixed with hyperlipemic rabbit plasma and subjected to ultracentrifugation the labelled fraction with density less than 1.2 g/ml is larger than when either lipoprotein or TGase is omitted. Chromatography of the fraction with density less than 1.2 g/ml shows the presence of peaks which are not present in the denser material. Since their elution positions indicate that they have higher molecular weights than PIIIP it is concluded that they consist of [125I]PIIIP which had been crosslinked by TGase and bound to lipoprotein. Low concentrations of similar low density, high molecular weight PIIIP antigens were found in normal human plasma and pooled sera from angiography subjects. In two out of seven infarct patients an unusually large fraction of the PIIIP antigen in the serum was found in a very high molecular weight peak containing low density material. It is speculated that this may arise from atherosclerotic lesions.
Bowness
J M
JM
Department of Biochemistry and Molecular Biology, University of Manitoba, Winnipeg, Canada.
Tarr
A H
AH
D000818:Animals; D000941:Antigens / Q000378:metabolism; D001161:Arteriosclerosis / Q000276:immunology; D003432:Cross-Linking Reagents / Q000378:metabolism*; D006801:Humans; D006949:Hyperlipidemias / Q000276:immunology; D008074:Lipoproteins / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D008099:Liver / Q000276:immunology; D008970:Molecular Weight; D010446:Peptide Fragments / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D011347:Procollagen / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D011817:Rabbits; D011503:Transglutaminases / Q000378:metabolism; D014461:Ultracentrifugation
D000941:Antigens; D003432:Cross-Linking Reagents; D008074:Lipoproteins; D010446:Peptide Fragments; D011347:Procollagen; C041876:procollagen Type III-N-terminal peptide; D011503:Transglutaminases