title: Apolipoprotein B-100 is the major form of this apolipoprotein secreted by human intestinal Caco-2 cells.
abstract: Although the discovery of stop codon has explained the mechanism for the formation of the intestinal marker, apolipoprotein B-48, the dispute regarding the presence of apolipoprotein B-100 in the intestine is still unsettled. To further investigate the characteristics of intestinal apolipoprotein B, the newly developed human colonic adenocarcinoma Caco-2 cells which express functional properties of the differentiated enterocytes, were used. SDS-polyacrylamide gel electrophoresis analyses of the intact culture medium or its lipoproteins of d less than 1.23 g/ml showed the presence of only a single protein band of apolipoprotein B-100 with no detectable apolipoprotein B-48. After immunoblotting with oligoclonal antibodies to the amino-terminal peptide of apolipoprotein B, a trace amount of apolipoprotein B-48 was observed in the isolated lipoproteins, but not in the intact culture medium. These results suggest that apolipoprotein B-100 is the major form of apolipoprotein B secreted by human intestinal cells.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City 73104.
authors.forename: D M
authors.initials: DM
authors.lastname: Lee
authors.forename: N
authors.initials: N
authors.lastname: Dashti
authors.forename: T
authors.initials: T
authors.lastname: Mok
mesh_terms: D000230:Adenocarcinoma; D000596:Amino Acids / Q000032:analysis; D053299:Apolipoprotein B-100; D001055:Apolipoproteins B / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003110:Colonic Neoplasms; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D015151:Immunoblotting
chemical_list: D000596:Amino Acids; D053299:Apolipoprotein B-100; D001055:Apolipoproteins B