lectins that agglutinate red blood cells (rbcs) were demonstrated in anopheles stephensi mosquito midgut extracts using human (four groups: a, b, ab and o, rh+) rat, sheep and rabbit blood cells. only rabbit rbcs showed agglutination reaction against the midgut extracts. significant differences in hemagglutinin titers and carbohydrate specifity were detected between male and female mosquitoes a...

The receptor specificities of four Escherichia coli cloned hemagglutinins, AFA-I, AFA-III, F1845 fimbriae, and the Dr hemagglutinin were studied. Evidence is provided that all four hemagglutinins recognize as their receptor the Dr blood group antigen. However, results of experiments using enzyme-treated erythrocytes and monoclonal antibodies indicate that the four adhesins recognize different e...

Binding of influenza viruses to target cells is mediated by the viral surface protein hemagglutinin. To determine the presence of binding sites for influenza A viruses on cells and tissues, soluble hemagglutinins of the H7 and H9 subtype were generated by connecting the hemagglutinin ectodomain to the Fc portion of human immunoglobulin G (H7Fc and H9Fc). Both chimeric proteins bound to differen...

Two strains of an antigenically intermediate human adenovirus were isolated from eye specimens from cases of conjunctivitis. The viruses were doubly neutralized by antisera to adenoviruses 15 and 29 but possessed the hemagglutinins of adenovirus 8 or 9.

The unpredictable mutations in the proteins from influenza A virus lead to the great difficulty in prevention of possible outbreak of bird flu and pandemic/epidemic of influenza. This unpredictability is due to the fact that we know little about the causes that lead to the mutations. In three of our recent studies on the hemagglutinins from influenza A virus, we unintentionally noticed the peri...

The 1918 influenza pandemic caused more than 40 million deaths and likely resulted from the introduction and adaptation of a novel avian-like virus. Influenza A virus hemagglutinins are important in host switching and virulence. Avian-adapted influenza virus hemagglutinins bind sialic acid receptors linked via alpha2-3 glycosidic bonds, while human-adapted hemagglutinins bind alpha2-6 receptors...

The Technicon autoanalyzer system used for the detection of homologous human hemagglutinins has been modified for the detection of hemagglutinins to sheep red blood cells. Antibody quantitation was obtained by plotting the optical density (OD) readings of peak heights of a serially diluted reference serum versus the serum dilutions. When the OD of the peak height of an unknown sample fell withi...

The extracts from 30 species of the green algae were examined for hemagglutination activity with a variety different animal and human erythrocytes which untreated treated enzymes. Almost all showed at least toward one type tested. Strong was detected in 5 Chlorophyta (Anadyomene plicata, Avrainvillea erecta, Boodlea struveoides, Halimeda velasquezii discoidea) enzyme-treated rabbit sheep erythr...

The viruses that caused the three influenza pandemics of the twentieth century in 1918, 1957, and 1968 had distinct hemagglutinin receptor binding glycoproteins that had evolved the capacity to recognize human cell receptors. We have determined the structure of the H2 hemagglutinin from the second pandemic, the "Asian Influenza" of 1957. We compare it with the 1918 "Spanish Influenza" hemagglut...