Influenza hemagglutinin, the receptor-binding and membrane fusion protein of the virus, is a prototypic model for studies of biological membrane fusion in general. To elucidate the minimum number of hemagglutinin trimers needed for fusion, the kinetics of fusion induced by reconstituted vesicles of hemagglutinin was studied by using single-vesicle image analysis. The surface density of hemagglu...

Ninety-five isolates of Haemophilus paragallinarum were classified serologically by a hemagglutinin serotyping scheme, and the results were compared with results from agglutinin serotyping of the same isolates. Of the isolates, 65 were from Australia, 5 were from Japan, 6 were from the Federal Republic of Germany, 7 were from the United States, and 12 were from South Africa. Seven hemagglutinin...

Heparin inhibited hemagglutination (HA) by equine arteritis virus (EAV) as well as did HA by Aujeszky's disease virus (ADV), but failed to inhibit HA by parainfluenza virus type 3 (PIV-3). The minimal concentration of heparin required to inhibit 8 HA U of EAV was 0.1 U/ml. In addition, most EAV hemagglutinin was retained by heparin acrylic beads, as was ADV hemagglutinin, but was not PIV-3 hema...

sequence analysis and phylogenetic study of hemagglutinin (ha) gene of h9n2 subtype of avian influenza virus isolates (outbreaks of 1998-2002) in tehran province (iran) were studied. two sets of forward and reverse primers in highly conserved regions, based on sequences of ha gene in genbank, were designed. pcr products of a 430-bp fragment of 16 isolates were sequenced and then were aligned wi...

Botulism is a disease involving intoxication with botulinum neurotoxins (BoNTs), toxic proteins produced by Clostridium botulinum and other clostridia. The 150 kDa neurotoxin is produced in conjunction with other proteins to form the botulinum progenitor toxin complex (PTC), alternating in size from 300 kDa to 500 kDa. These progenitor complexes can be classified into hemagglutinin positive or ...

In this study we describe a beads-based assay for rapid, sensitive and specific isolation and detection of influenza vaccine hemagglutinin (HA). Amplification of the hemagglutinin signal resulted from binding of an electrochemical label as quantum dots (QDs). For detection of the metal and protein part of the resulting HA-CdTe complex, two differential pulse voltammetric methods were used. The ...

Dick, Elliot C. (Tulane University School of Medicine, New Orleans, La.) and William J. Mogabgab. Characteristics of para-influenza 1 (HA-2) virus. III. Antigenic relationships, growth, interaction with erythrocytes, and physical properties. J. Bacteriol. 83:561-571. 1962-Hemagglutination-inhibition tests with rabbit and rooster immune sera showed HA-2-like strains of para-influenza 1 to be nea...

The glycan receptor binding and specificity of influenza A viral hemagglutinin (HA) are critical for virus infection and transmission in humans. However, ambiguities in the interpretation of the receptor binding specificity of hemagglutinin from human- and avian-adapted viruses have prevented an understanding of its relationship with aerosol transmissibility, an exclusive property of human-adap...

UNLABELLED Influenza viruses expressing chimeric hemagglutinins (HAs) are important tools in the quest for a universal vaccine. Using cryo-electron tomography, we have determined the structures of a chimeric HA variant that comprises an H1 stalk and an H5 globular head domain (cH5/1 HA) in native and antibody-bound states. We show that cH5/1 HA is structurally different from native HA, displayi...

The mitogenic activity of influenza virus is a function of the hemagglutinin (HA) molecule. Purified HA is mitogenic for murine B lymphocytes but not T lymphocytes. Furthermore, like the intact virus, HA of the H2 (but not H3) subtype is mitogenic only for B cells expressing the class II major histocompatibility complex glycoprotein I-E. Since virus bearing uncleaved HA is as mitogenic as virus...