Growth of a transplanted, isologous mammary carcinoma resulted in depressed titers of serum properdin and Shigella parodysenteriae antibody in mice. This tumor had no apparent deleterious influence on natural antisheep hemagglutinins. Tumor antigen preparations did not produce these effects. The likelihood that these alterations in immune response are secondary rather than direct effects is sug...

Since the discovery of ricin by Kobert in 1887, considerable interest has been shown in the hemagglutinins obtainable from plants. The study of them has been somewhat overshadowed by the more recently discovered serum agglutinins, which they so remarkably resemble in action. They have, however, played an important part in immunological research throughout its history. Ricin, the extremely toxic...

Agglutination of red blood cells (RBCs), including chicken RBCs (cRBCs), has been used extensively to estimate viral titer, to screen glycan-receptor binding preference, and to assess the protective response of vaccines. Although this assay enjoys widespread use, some virus strains do not agglutinate RBCs. To address these underlying issues and to increase the usefulness of cRBCs as tools for s...

Feline herpesvirus type 1 (FHV-1) is a causative agent of feline viral rhinotracheitis and belongs to the subfamily Alphaherpesvirinae of the family Herpesviridae. Since first isolated in 1958 by Crandell and Maurer, FHV-1 is distributed worldwide and is the most clinically significant agent for respiratory infections in cats. In this review, we describe the recent findings with properties and ...

Hemagglutinins for sheep red blood cells were detected in sera from JM virus-infected single-comb White Leghorn (susceptible S line) chickens. The agglutinins were not sedimented at 97,000 x g and were not affected by freezing and thawing, possibly indicating a soluble hemagglutinating factor. Agglutination titers were read in a relatively short period, after 4 hr of incubation at 4 C. The usef...

The 2009 pandemic influenza A (H1N1) virus exhibits hemagglutinin protein sequence homology with the 1918 pandemic influenza virus. We found that human monoclonal antibodies recognized the Sa antigenic site on the head domains of both 1918 and 2009 hemagglutinins, a site that is hypervariable due to immune selection. These antibodies exhibited high potency against the 2009 virus in vitro, and o...

The destruction of viral-infected and tumor cells is mediated in part via the lysis receptor of natural killer (NK) cells, NKp46. The nature, however, of its lysis ligands expressed on target cells is poorly defined. Recently, we have identified a novel functional interaction between the lysis receptors NKp46 and NKp44 and the hemagglutinin of influenza and hemagglutinin-neuroaminidase of Senda...

Fusion protein strategies are useful tools to enhance expression and to support the development of purification technologies. The capacity of fusion protein strategies to enhance expression was explored in tobacco leaves and seeds. C-terminal fusion of elastin-like polypeptides (ELP) to influenza hemagglutinin under the control of either the constitutive CaMV 35S or the seed-specific USP promot...