Search results for "hemagglutinin"

Atomic structure of the major capsid protein of rotavirus: implications for the architecture of the virion

2001

The structural protein VP6 of rotavirus, an important pathogen responsible for severe gastroenteritis in children, forms the middle layer in the triple-layered viral capsid. Here we present the crystal structure of VP6 determined to 2 A resolution and describe its interactions with other capsid proteins by fitting the atomic model into electron cryomicroscopic reconstructions of viral particles. VP6, which forms a tight trimer, has two distinct domains: a distal beta-barrel domain and a proximal alpha-helical domain, which interact with the outer and inner layer of the virion, respectively. The overall fold is similar to that of protein VP7 from bluetongue virus, with the subunits wrapping …

Molecular evolution: Evidence for the monophyletic origin of multicellular animals

1995

Cutting edge: Multiple sclerosis-like lesions induced by effector CD8 T cells recognizing a sequestered antigen on oligodendrocytes.

2008

Abstract CD8 T cells are emerging as important players in multiple sclerosis (MS) pathogenesis, although their direct contribution to tissue damage is still debated. To assess whether autoreactive CD8 T cells can contribute to the pronounced loss of oligodendrocytes observed in MS plaques, we generated mice in which the model Ag influenza hemagglutinin is selectively expressed in oligodendrocytes. Transfer of preactivated hemagglutinin-specific CD8 T cells led to inflammatory lesions in the optic nerve, spinal cord, and brain. These lesions, associating CD8 T cell infiltration with focal loss of oligodendrocytes, demyelination, and microglia activation, were very reminiscent of active MS le…

Erythrocyte agglutinins in the blood of certain Ascidians

1975

Plasma from Ciona intestinalis, Phallusia mamillata and Ascidia malaca possess hemagglutinin for a variety of erythrocytes. Results obtained by physical and chemical treatments suggest that hemagglutinin for Phallusia mamillata and Ascidia malaca may be a protein or a protein-like substance.

Effects of forest patch size on physiological stress and immunocompetence in an area-sensitive passerine, the Eurasian treecreeper ( Certhia familiar…

2004

We manipulated the primary brood size of Eurasian treecreepers (Certhia familiaris) breeding in different sized forest patches (0.5-12.8 ha) in moderately fragmented landscapes. We examined the effects of brood size manipulation (reduced, control, enlarged) and forest patch size on physiological stress (heterophil-lymphocyte ratios; H/L), body condition and cell-mediated immunocompetence (phytohaemagglutinin test). Nestlings' H/L ratios were negatively related to forest patch area in control and enlarged broods, whereas no effects were found in reduced broods. The effects of forest patch area were strongest in enlarged broods, which had, in general, twofold higher H/L ratios than control an…

Sabella spallanzanii mucus contain a galactose-binding lectin able to agglutinate bacteria. Purification and characterization

2019

Lectins are present in almost all living organisms and are involved in several biological processes, including immune responses. In the present study, a calcium dependent galactose-binding lectin exhibiting an apparent MW of 43 kDa has been characterized and purified from the mucus of the polychaete Sabella spallanzanii by using both affinity chromatography and high-pressure liquid chromatographic methods. Its agglutinating activity towards rabbit erythrocytes was significantly modified by the addition of calcium or EDTA. The activity was optimal at temperature values comprised between 4 and 18 °C, maintain a 50% of activity between 20 and 37 °C, was significant deleted after exposure at 50…

Proliferative response of synovial fluid and peripheral blood mononuclear cells to arthritogenic and non-arthritogenic microbial antigens and to the …

1990

Cellular immune responses to microbial antigens have been implicated in the pathogenesis of some forms of arthritis including reactive arthritis, Reiter's syndrome, ankylosing spondylitis and rheumatoid arthritis. We investigated the proliferative T cell responses of paired peripheral blood (PB) and synovial fluid (SF) mononuclear cells (MC) to so-called arthritogenic bacteria (Yersinia enterocolitica and Salmonella typhimurium), to control antigens, such as Candida albicans, mumps virus and purified protein derivative, to the recombinant mycobacterial 65-kDa heat-shock protein (hsp 65) and the mitogen phytohemagglutinin (PHA) in 16 patients with different inflammatory rheumatic diseases. T…

Inhibition of the pro-inflammatory mediators' production and anti-inflammatory effect of the iridoid scrovalentinoside.

2007

We have studied scrovalentinoside, an iridoid with anti-inflammatory properties isolated from Scrophularia auriculata ssp. pseudoauriculata, as an anti-inflammatory agent in different experimental models of delayed-type hypersensitivity. We found that scrovalentinoside reduced the edema induced by oxazolone at 0.5 mg/ear and sheep red blood cells at 10 mg/kg. The observed effect occurred during the last phase or inflammatory response; during the earlier phase or induction of the delayed-type hypersensitivity reaction, no significant activity was noted. Thus, scrovalentinoside reduced both the edema and cell infiltration in vivo and reduced lymphocyte proliferation in vitro, affecting the cy…

Surface and virulence properties of environmental Vibrio cholerae non-O1 from Albufera Lake (Valencia, Spain).

1990

A total of 140 environmental Vibrio cholerae non-O1 isolates, together with several culture collection strains from both environmental and clinical sources, were studied in relation to hemagglutination, surface hydrophobicity, and the enzymatic, hemolytic, cytotoxic, and enterotoxic activities of their extracellular products. A total of 78 and 62% of the strains produced hemagglutinins and exohemagglutinins, respectively. Four different hemagglutinating and two exohemagglutinating activities were found by using eight sugars in the inhibition assays. Cell-bound mannose-sensitive hemagglutination was detected mainly in chicken blood, whereas fucose-sensitive hemagglutination was recorded only…

Isolation and characterization of a fish F-type lectin from gilt head bream (Sparus aurata) serum.

2007

A novel fucose-binding lectin, designated SauFBP32, was purified by affinity chromatography on fucose-agarose, from the serum of the gilt head bream Sparus aurata. Electrophoretic mobility of the subunit revealed apparent molecular weights of 35 and 30 kDa under reducing and non-reducing conditions, respectively. Size exclusion analysis suggests that the native lectin is a monomer under the selected experimental conditions. Agglutinating activity towards rabbit erythrocytes was not significantly modified by addition of calcium or EDTA; activity was optimal at 37 degrees C, retained partial activity by treatment at 70 degrees C, and was fully inactivated at 90 degrees C. On western blot anal…