Differential affinity of natural haemagglutinin of Macrobrachium rosenbergii towards vertebrate erythrocytes: effect of sex, size and moult stage on haemagglutination titre.

Lectins play important role in innate immunity of animals. The affinity of the natural haemagglutinin of the giant freshwater prawn Macrobrachium rosenbergii towards vertebrate erythrocytes and its level with relation to sex, size and moult stages were studied. The strongest agglutinating titres in haemolymph of prawns were marked against guinea pig, chicken, Clarias batrachus, and rabbit erythrocytes, and the weakest towards cattle, dog, horse and goat erythrocytes. A moderately agglutinating titre was evident in duck and human erythrocytes. The haemolymph of adult, male or intermoult stage prawns weighing more than 100 g had the highest haemagglutinating activity as compared to their respective counterparts with varied responses observed towards various erythrocytes.

Galectin-1, an alternative signal for T cell death, is increased in activated macrophages

Galectin-1 belongs to an evolutionarily conserved family of animal ß-galactoside-binding proteins, which exert their functions by crosslinking the oligosaccharides of specific glycoconjugate ligands. During the past decade, attempts to identify the functional role of galectin-1 suggested participation in the regulation of the immune response. Only in the last few years has the molecular mechanism involved in these properties been clearly elucidated, revealing a critical role for galectin-1 as an alternative signal in the generation of T cell death. In the present study we will discuss the latest advances in galectin research in the context of the regulation of the immune response, not only at the central level but also at the periphery. Moreover, we will review the purification, biochemical properties and functional significance of a novel galectin-1-like protein from activated rat macrophages, whose expression is differentially regulated according to the activation state of the cells. The novel role of a carbohydrate-binding protein in the regulation of apoptosis is providing a breakthrough in galectin research and extending the interface between immunology, glycobiology and clinical medicine

Toxocariasis sistémica en el paciente adulto / Systemic toxocariasis in adult patient

We report a retrospective review of 8 patients (one male), aged 19 to 31 years old, with systemic toxocariasis (visceral larva migrans), seen at the Salvador Hospital of Santiago. 4 cases had heart involvement, three had lung involvement and in 2, several organs were affected. Seven cases had leukocytosis (range 14, 5 to 160 x 10 9/1) and all had eosinophilia (35 to 90 percent). Serum ELISA titers for toxocara sp were positive in all cases, ranging from 64 to 1000. Six patients were treated with thiabendazole and one with albendazole. Steroids or hydroxiurea were administered to patients with heart failure or hyperleukocytosis. Subjects with lung involvement recovered quickly but those with cardiac compromise had a partial recovery with frequent decompensations of their cardiac failure and one death. Eosinophilia lasted up to 20 years, in spite of specific treatment. We emphasize the importance of infection prevention, accuracy of diagnosis and the severity of cardiac damage in the adult patient

Soluble haemagglutinin of classical vibrios: isolation and protection against cholera by its antibodies.

Soluble haemagglutinin was isolated from a late culture supernatant of classical Vibrio cholerae grown in casein-peptone broth with aeration by saturated ammonium sulphate precipitation in the cold, followed by gel filtration, electrophoresis, ether extraction and electrophoresis respectively. The antigen was found to consist of three protein fractions with different electrophoretic mobilities. Antibodies to these fractions afforded low but significant protection against oral challenges with homologous classical V. cholerae in the infant mouse cholera model.

The study of intestinal immunity against V. cholerae: purification of V. cholerae El Tor haemagglutinin and the protective role of its antibody in experimental cholera.

V. cholerae El Tor Ogawa strain O17SR grown on trypticase soy agar were extracted with 0.05 M cyclohexylamino propane sulfonic acid (CAPS) pH 9.5 at 37 degrees C for 1 hour. The bacteria were then removed by centrifugation and millipore filtration. The filtered fluid, after being dialysed against many changes of cold distilled water, was concentrated and passed through Sephadex G200 column. Three protein profiles were eluted out with 0.05 M Tris buffer pH 8.6. The haemagglutinin and the bacterial lipopolysaccharide (LPS) were confined to the first profile. They were subsequently separated by agarose gel electrophoresis. The haemagglutinin was found to be more anodic than the LPS. After homogenization of the gel strips containing the haemagglutinin followed by centrifugation at 9,000 g pure haemagglutinin was obtained in the supernatant. Rabbit aniserum against pure haemagglutinin contained protective antibodies against V. cholerae infection in the baby mouse model. Specific antibodies prepared from this antiserum was as protective as the antibodies directed against whole V. cholerae and heat stable somatic antigens of V. cholerae upon the same weight unit.

Study of intestinal immunity against V. cholerae: role of antibody to V. cholerae haemagglutinin in intestinal immunity.

Cell-bound haemagglutinin as an adhesive factor of Vibrio cholerae has been partially purified from E1 Tor vibrios using 0.05 M cyclohexylaminopropane sulfonic acid buffer pH 9.5 and gel filtration column chromatography. Rabbits were immunized with the precipitin complexes of the haemagglutinin and its antibody. The antiserum is tested for the protective ability against the oral challenge with Vibrio cholerae strain of which the haemagglutinin has been prepared. The results indicate definite protection of the haemagglutinin antiserum.