TY - JOUR
T1 - Immunocytochemical demonstration of the lysosomal enzyme alpha-glucosidase in the brush border of human intestinal epithelial cells
AU - Fransen, J. A.
AU - Ginsel, L. A.
AU - Cambier, P. H.
AU - Klumperman, J.
AU - Oude Elferink, R. P.
AU - Tager, J. M.
PY - 1988
Y1 - 1988
N2 - In investigations on the intracellular transport route(s) of lysosomal enzymes in polarized epithelial cells, we used immunocytochemical methods to localize lysosomal alpha-glucosidase in human small-intestinal epithelial cells. Two monoclonal antibodies which can discriminate between different biosynthetic forms of this enzyme were used. One monoclonal antibody, 43D1, which recognizes all forms of the enzyme, showed labeling of the Golgi apparatus, the lysosomes and, unexpectedly, of the brush border of the cells. Multivesicular bodies were free of label. In contrast, monoclonal antibody 43G8, which recognizes all forms except the 110,000 Da precursor of alpha-glucosidase, showed labeling of the lysosomes only. This leads us to conclude that the 110,000 Da precursor form of alpha-glucosidase is present in the Golgi apparatus and the brush border of human small-intestinal epithelial cells. Moreover, biochemical experiments show that this precursor copurifies with sucrase, a typical brush-border marker, when a partially purified microvilli fraction is prepared
AB - In investigations on the intracellular transport route(s) of lysosomal enzymes in polarized epithelial cells, we used immunocytochemical methods to localize lysosomal alpha-glucosidase in human small-intestinal epithelial cells. Two monoclonal antibodies which can discriminate between different biosynthetic forms of this enzyme were used. One monoclonal antibody, 43D1, which recognizes all forms of the enzyme, showed labeling of the Golgi apparatus, the lysosomes and, unexpectedly, of the brush border of the cells. Multivesicular bodies were free of label. In contrast, monoclonal antibody 43G8, which recognizes all forms except the 110,000 Da precursor of alpha-glucosidase, showed labeling of the lysosomes only. This leads us to conclude that the 110,000 Da precursor form of alpha-glucosidase is present in the Golgi apparatus and the brush border of human small-intestinal epithelial cells. Moreover, biochemical experiments show that this precursor copurifies with sucrase, a typical brush-border marker, when a partially purified microvilli fraction is prepared
M3 - Article
C2 - 3068058
SN - 0171-9335
VL - 47
SP - 72
EP - 80
JO - European Journal of Cell Biology
JF - European Journal of Cell Biology
IS - 1
ER -