Synthesis and Evaluation of Biotinylated Bivalent HistoBlood Group Antigens for Capturing Human Noroviruses

Snow Mountain Virus recovery by synthetic human histo-blood group antigens is heavily influenced by matrix effects

Noroviruses are known to bind to histo-blood group antigens (HBGAs) and the specific binding patterns depend on the virus genotype. However, the development of point-of-care diagnostic assays based on this binding has been challenging due to low assay sensitivity. This study utilized a well-defined stool collection from a GII.2 Snow Mountain Virus (SMV) human challenge study to investigate virus recovery from stool and emesis samples using HBGA-coated beads. SMV was recovered from H type III-coated beads for 13 stool specimens out of 27 SMV-positive specimens tested. After adjusting for non-specific binding to PEG-coated beads, the mean percent recovery by H type III-coated beads was 308.11% +/− 861.61. Recovery by H type III ligands was subject-specific and weakly correlated with stool consistency. Input virus titer was not correlated with SMV recovery. The results suggest that the generally low virus recovery we observed may be due to bead saturation or hindrance by existing glycans in the matrix that precluded the virus from being captured by the synthetic glycans. These results indicate a strong role for subject-specific and matrix effects in HBGA binding by SMV. Further investigation of the nature of this interference is needed to facilitate development of high sensitivity diagnostic assays.

Synthesis of biotinylated bivalent zanamivir analogs as probes for influenza viruses

The synthesis of a biotinylated bivalent zanamivir analog as a probe for influenza viruses is reported. The compound was used in a ‘glycan’ based sandwich assay; where glycans were immobilized on glass slides to capture strains of influenza A H1N1, A/Brisbane/59/2007 virus; the biotinylated bivalent zanamivir analog-labeled streptavidin complex was used as reporter. This research strongly suggests that glycans can be used for capturing and reporting influenza viruses and the biotinylated compounds can be used as probes for capturing and isolating influenza viruses from complex mixtures.