Shiga Toxin Binding to Isolated Porcine Tissues and Peripheral Blood Leukocytes

ABSTRACT Shiga toxin (Stx) binding sites in porcine tissues and leukocytes were identified by the use of Stx overlay and anti-CD77/Gb3 immunoassays. Stx1 and Stx2 bound to similar tissue locations and leukocytes, although some differences were noted. Previously unreported Stx binding sites were identified in kidney tubules, intestinal lymphoid aggregates, sinusoidal liver cells, alveolar macrophages, and peripheral blood leukocytes.

A TEM study on the uptake of AMI 25 by sinusoidal liver cells

Earlier studies have indicated that the liver plays a major role in the clearance of Ami 25 colloidal particles, consisting of dextran-stabilized superparamagnetic ferric oxyhydroxide citrate, used for increasing the contrast during NMR imaging of the liver. The uptake of these particles by different cell types in the rat liver was studied, at time intervals ranging from 3 minutes to 1 month.Two different dose levels were used, i.e. a single, low dose of 1,1 mg Fe/kg, comparable to the dose given to patients, and a single, tenfold dose of 11,3 mg Fe/kg. Controls received saline injections. I.v. injections were given to young adult male Wistar rats. After perfusion fixation of the liver with isotonic, buffered, 1.5% glutaraldehyde, at 10 - 12 cm H2O pressure during 7 min at 20 °C and a flow rate of 7ml/min, tissue blocks were postfixed in 1% osmium, dehydrated in ethanol, and embedded in Epon. Ultrathin sections were observed in the transmission electron microscope. In addition, Fe determinations were performed on total liver and on isolated sinusoidal cells.

Carbohydrate recognition systems in avian sinusoidal liver cells

We studied the carbohydrate recognition systems on liver sinusoidal cells of adult chicken and 20-day-old embryos. We localized and quantified the binding sites for glycoproteins exposing terminal N-acetylglucosamine (GlcNAc), mannose and galactose (Gal) residues. Sinusoidal liver cells from animals of both ages express on their cell surfaces binding sites for GlcNAc, mannose and galactose residues, while hepatocytes bind glycoproteins with GlcNAc resiudes. The gold particles distribution on Kuffer cells depend on the binding sites and the age considered. Binding sites for GlcNAc and Gal residues are generally present as clusters of gold granules, while mannose-specific binding sites are always as single gold granules. Ligand-gold complexes bound on endothelial cells are always present on the coated regions of the cell surface. The number of GlcNAc and Gal-specific receptors expressed on the cell surface of Kupffer cells undergoes modifications between embryonal and adult life.