concanavalin-a and Sandhoff-Disease

Lectin histochemical studies were performed on selected formalin-fixed, paraffin-embedded tissues of patients affected with the O variant of GM2-gangliosidosis (i.e., Sandhoff's disease). The purpose was to identify specific sugar residues of undegraded "stored" substances in cytoplasm of affected cells. We studied neural tissues from 13 patients, visceral tissues from four patients, and placentae from three affected fetuses. Neurons in all 13 cases studied stained with Concanavalia ensiformis agglutinin (Con A) and with Ulex europaeus agglutinin-I (UEA-I). Succinylated wheat germ agglutinin (S-WGA) stained affected visceral cells and astrocytes and macrophages in the central nervous system. These results demonstrate that alpha-D-mannosyl and alpha-L-fucosyl residues, which bind Con A and UEA-I, respectively, are present in affected neurons. Furthermore, they revealed the affected non-neuronal cells and astrocytes contain complex carbohydrates with nonreducing terminal beta-N-acetylglucosamine, which binds S-WGA.

Topics: Brain; Carbohydrates; Child, Preschool; Concanavalin A; Female; Fetus; Gestational Age; Histocytochemistry; Humans; Infant; Lectins; Male; Plant Lectins; Sandhoff Disease; Spinal Cord; Wheat Germ Agglutinins

Since we observed the normalization of intracellular hydrolases in some cell lines of I-cell disease (ICD) by 88 mmol/l sucrose, we have hypothesized that the degree of responses of the hydrolases might be due to biochemical heterogeneity among ICD. In this study the changes of intracellular lysosomal enzymes as well as Golgi enzymes including N-acetylglucosaminyl phosphotransferase (GlcNAcPTase) and extracellular hexosaminidase (HEX) were investigated using normal and ICD fibroblasts. Sucrose loading induced the activities of intracellular HEX and GlcNAcPTase simultaneously only in responding-type ICD cells, and not in nonresponding-type ICD cells, indicating that two biochemical heterogeneous groups exist in ICD.

Topics: beta-N-Acetylhexosaminidases; Cells, Cultured; Concanavalin A; Endocytosis; Fibroblasts; Humans; Mucolipidoses; Phosphotransferases; Plant Lectins; Plants, Toxic; Ricinus; Sandhoff Disease; Sucrose; Transferases (Other Substituted Phosphate Groups)

Topics: beta-Galactosidase; Biological Transport; Cell Line; Concanavalin A; Endocytosis; Fibroblasts; Galactosidases; Gangliosidoses; Hexosaminidases; Humans; Kinetics; Sandhoff Disease; Temperature