Epitopes of apolipoprotein B-100 and B-48 in both liver and intestine. Expression and evidence for local synthesis in recessive abetalipoproteinemia.
The presence of apolipoprotein (apo) B in liver and intestine from a patient with abetalipoproteinemia was evaluated by immunohistochemistry with a polyclonal and six monoclonal antibodies to different apo B-48 and B-100 epitopes. In normal liver, apo B was present inside and outside hepatocytes. The patients liver exhibited staining in the cytoplasm with the polyclonal and three monoclonal antibodies. By immunoelectron-microscopy, apo B was found to be present in the smooth endoplasmatic reticulum and the Golgi complex. Normal intestinal epithelium was labeled with polyclonal and all monoclonal antibodies, including those specific for apo B-100. The patients epithelium stained with polyclonal and six monoclonals, and apo B was present in the Golgi complex. Thus, normal intestinal mucosa expressed apo B-48 and B-100 epitopes, which indicates apo B-100 synthesis in the gut. The synthesis of the apo B molecule in the patient seems to be retained in both liver and gut, which suggests a posttranslational defect.
D000012:Abetalipoproteinemia / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000911:Antibodies, Monoclonal; D053299:Apolipoprotein B-100; D053283:Apolipoprotein B-48; D001055:Apolipoproteins B / Q000032:analysis / Q000096:biosynthesis* / Q000097:blood; D004386:Duodenum / Q000378:metabolism* / Q000648:ultrastructure; D000939:Epitopes / Q000032:analysis*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005808:Genes, Recessive; D006801:Humans; D007583:Jejunum / Q000378:metabolism* / Q000473:pathology; D008099:Liver / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D008854:Microscopy, Electron
D000911:Antibodies, Monoclonal; D053299:Apolipoprotein B-100; D053283:Apolipoprotein B-48; D001055:Apolipoproteins B; D000939:Epitopes; D005230:Fatty Acids, Nonesterified