IMMUNOFLUORESCENCE STUDIES OF APOLIPOPROTEIN-B IN INTESTINAL-MUCOSA - ABSENCE IN ABETALIPOPROTEINEMIA

  • 1 January 1979
    • journal article
    • research article
    • Vol. 76  (2) , 288-292
Abstract
During fat absorption, active synthesis of cholesterol, phospholipids, and specific apolipoproteins are required for chylomicron formation and secretion. In the inherited disease abetalipoproteinemia, chylomicrons cannot be made in response to fat feeding, and they as well as low and very low density lipoproteins are completely absent from plasma. The genetic defect in the disease is presumed to be an inability to synthesize apolipoprotein B, the apoprotein common to all the above lipoprotein classes, but such a defect was not directly demonstrated. With peroral intestinal biopsies and immunofluorescence techniques, the presence and intracellular localization of apolipoprotein B was demonstrated within jejunal epithelial cells of 5 normal subjects. Its content increases markedly after fat feeding. In 2 patients with abetalipoproteinemia no apolipoprotein B was seen by immunofluorescence techniques in the jejunal mucosa in the fasting stage or after a fatty meal. Intestinal synthesis of apolipoprotein B appears not to occur to abetalipoproteinemia.