(386d) Molecular Beacons for Early Diagnostics of Influenza Viruses

Diagnostics plays a vital role in the detection of epidemiologically important viruses and identification of appropriate treatments. Influenza is one of the most important infectious diseases of humans due to the emergence of novel strains during each flu season. The reassortment of genes between two (or more) influenza viruses of the same or different subtype leads to the formation of genetically novel viruses. Since the efficacy of most drugs is the highest when administered within 48 hours of infection, rapid diagnosis is crucial to successful treatment. Traditionally immunological, nucleic acid-based and infectivity-based methods have been used to perform virus analysis, but these methods can take up to weeks to enable detection. Molecular beacons (MBs) are one among the promising technologies that are used for gene detection in living cells. MBs are single-stranded oligonucleotide probes that posses a stem-loop structure consisting of a fluorophore at one end and a quencher at the other. The probes are specific for a target nucleotide sequence and produce fluorescence upon target binding. To preserve the duplex stability of MB in living cells, they have been modified with a 2'-O-methyl substitution and phosphorothioate internucleotide linkages to avoid endogenous nuclease degradation. A non-invasive strategy for intracellular delivery of the MBs is used which consists of the HIV-1-derived Tat peptide. This Tat-based method coupled with nuclease-resistant MBs can provide powerful means for rapid detection and a potential diagnostic tool that can even distinguish between subtypes of viruses with high specificity and sensitivity. This talk will focus on recent progress made in this area using Influenza A virus infection as a model system.