Serological responses to experimental Norwalk virus infection measured using a quantitative duplex time-resolved fluorescence immunoassay

A quantitative duplex time-resolved fluorescence assay, dissociation-enhanced lanthanide fluorescent immunoassay (DELFIA), was developed to measure Norwalk virus (NV)-specific IgA and IgG antibodies simultaneously. The duplex assay showed superior performance by detecting seroconversion following experimental NV infection at an earlier time point than a reference total immunoglobulin enzyme-linked immunosorbent assay (ELISA).

Serological correlate of protection against norovirus-induced gastroenteritis

Norovirus infection is the leading cause of acute nonbacterial gastroenteritis. Histoblood group antigens (HBGAs) are host susceptibility determinants for Norwalk virus (NV) infection. We hypothesized that antibodies that block NV-HBGA binding are associated with protection from clinical illness following NV exposure.

Analysis of protein-protein interactions in the feline calicivirus replication complex

Caliciviruses are a major cause of gastroenteritis in humans and cause a wide variety of other diseases in animals. Here, the characterization of protein-protein interactions between the individual proteins of Feline calicivirus (FCV), a model system for other members of the family Caliciviridae, is reported. Using the yeast two-hybrid system combined with a number of other approaches, it is demonstrated that the p32 protein (the picornavirus 2B analogue) of FCV interacts with p39 (2C), p30 (3A) and p76 (3CD). The FCV protease/RNA polymerase (ProPol) p76 was found to form homo-oligomers, as well as to interact with VPg and ORF2, the region encoding the major capsid protein VP1. A weak interaction was also observed between p76 and the minor capsid protein encoded by ORF3 (VP2). ORF2 protein was found to interact with VPg, p76 and VP2. The potential roles of the interactions in calicivirus replication are discussed.

A metagenomic comparison of endemic viruses from broiler chickens with runting stunting syndrome and from normal birds

Runting-stunting syndrome (RSS) in broiler chickens is an enteric disease that causes significant economic losses to poultry producers worldwide due to elevated feed conversion ratios, decreased body weight during growth, and excessive culling. Of specific interest are the viral agents associated with RSS which have been difficult to fully characterise to date. Past research into the aetiology of RSS has implicated a wide variety of RNA and DNA viruses however, to date, no individual virus has been identified as the main agent of RSS and the current opinion is that it may be caused by a community of viruses, collectively known as the virome. This paper attempts to characterise the viral pathogens associated with 2 – 3 week old RSS-affected and unaffected broiler chickens using next-generation sequencing and comparative metagenomics. Analysis of the viromes identified a total of 20 DNA & RNA viral families, along with 2 unidentified categories, comprised of 31 distinct viral genera and 7 unclassified genera. The most abundant viral families identified in this study were the Astroviridae, Caliciviridae, Picornaviridae, Parvoviridae, Coronaviridae, Siphoviridae, and Myoviridae. This study has identified historically significant viruses associated with the disease such as chicken astrovirus, avian nephritis virus, chicken parvovirus, and chicken calicivirus along with relatively novel viruses such as chicken megrivirus and sicinivirus 1 and will help expand the knowledge related to enteric disease in broiler chickens, provide insights into the viral constituents of a healthy avian gut, and identify a variety of enteric viruses and viral communities appropriate for further study.