The instant invention provides stable and novel lineage I WNV reverse genetics systems, and methods for making the reverse genetics systems, specifically, a fully-infectious lineage I WNV cDNA or repliconsystem engineered with one or more nucleotide sequences each encoding a reporter gene to be used in high throughputcell-based screening assays for the identification of novel antiflaviviral chemotherapeutics and / or vaccines effective to treat and / or immunize against infections by WNV and other emerging flaviviruses, such as, for example, JEV, SLEV, AV, KV, JV, CV, YV, TBEV, DENV-1, DENV-2, DENV-3, DENV-4, YFV and MVEV. The present invention further provides methods of high throughput screening of antiflaviviral compounds or improved derivatives thereof using novel lineage I WNV reverse genetics systems and / or cell lines stably containing the reverse genetics systems. Also, the invention provides novel pharmaceutical compositions comprising an attenuated lineage I WNV that is less virulent but similarly immunogenic as the parent WNV and is capable of providing a protective immune response in a host.
A method of inhibiting replication of a flavivirus in animal cells, and an oligonucleotide compound for use in the method are disclosed. The oligonucleotide analog (i) has a nuclease-resistant backbone, (ii) is capable of uptake by the cells, (iii) contains between 8-40 nucleotide bases, and (iv) has a sequence of at least 8 bases complementary to a region of the virus' positive strand RNAgenome that includes at least a portion of SEQ ID NOS:1-4. Exposure of cells infected with a flavivirus to the analog is effective to form within the cells, a heteroduplex structure composed of the virus ssRNA and the oligonucleotide, characterized by a Tm of dissociation of at least 45 ° C., and having disrupted base pairing between the virus' 5′ and 3′ cyclization sequences.
The present invention is directed to methods of treating flavivirus mediated diseases using siRNAs. The invention is based upon our findings in a mouse model that siRNAs directed against sequences conserved among multiple flaviviruses prevents and treats flavivirus infections. Accordingly, the present invention provides an isolated siRNA comprising a sense RNA and an antisense RNA strand or a single strand. The sense and the antisense RNA strands, or the single RNA strand, form an RNA duplex, and wherein the RNA strand comprises a nucleotide sequence identical to a target sequence of about 15 to about 30 contiguous nucleotides in flavivirus mRNA or mutant or variant thereof.
Methods and compositions concerning mutant flaviviruses with host range mutations. In some embodiments the invention concerns nucleotide sequences that encodemutantflavivirus proteins. Viruses comprising these sequences that display reduced replication in mammalian cells are provided. In further aspects of the invention, flavivirus vaccine compositions are provided. In another embodiment the invention provides methods for vaccination against flavivirus infection.
The invention encompasses nucleic acid molecules containing transcription units which encode the flavivirus M and E protein antigens. The flaviviruses include Japanese encephalitisvirus, dengue, yellow fevervirus and St. Louis encephalitisvirus. The nucleic acids function to provide the M and E protein antigens when the nucleic acid resides in an appropriate host cell, especially when the host cell is the cell of a subject. The invention also encompasses a vaccine whose active agent is the nucleic acid. The invention further encompasses the cultured host cells when they contain within them nucleic acid molecules containing the transcription units. The invention in addition encompasses a method of immunizing a subject against flavivirus infection by administering to the subject an effective amount of a vaccine containing a nucleic acid molecule containing the transcription unit of the invention.
The present invention is directed to an artificial nucleic acid and to a polypeptide suitable for use in the treatment or prophylaxis of an infection with a flavivirus, in particular an infection with yellow fevervirus or with dengue virus, or of a disorder related to such an infection. The present invention is also directed to a composition, preferably an immunogenic composition, comprising the artificial nucleic acid or the inventive polypeptide. In particular, the present invention concerns an immunogenic composition against a flavivirus, such as yellow fevervirus or dengue virus. Further, the invention concerns a kit, particularly a kit of parts, comprising the artificial nucleic acid, polypeptide or (immunogenic) composition. The invention is further directed to a method of treating or preventing a disorder or a disease, first and second medical uses of the artificial nucleic acid, polypeptide, composition, in particular the first and second medical uses of the immunogenic composition according to the invention.
Disclosed herein is a method for identifying flavivirus cross-reactive epitopes. Also provided are flavivirus E-glycoprotein cross-reactive epitopes and flavivirus E-glycoprotein cross-reactive epitopes having reduced or ablated cross-reactivity (and polypeptides comprising such epitopes), as well as methods of using these molecules to elicit an immune response against a flavivirus and to detect a flaviviral infection.
The invention provides recombinant flavivirus vaccines that can be used in the prevention and treatment of flavivirus infection. The vaccines of the invention contain recombinant flaviviruses including attenuating mutations.
The present invention provides methods for determining the susceptibility of a pathogenic flavivirus to anti-viral compounds. This invention also provides methods for determining anti-viral drug susceptibility in a patient infected with a flavivirus. This invention also provides a method for evaluating the biological effectiveness of a candidate anti-viral drug compound. The methods are useful for identifying effective drug regimens for the treatment of flaviviral infections, and identifying and assessing the biological effectiveness of potential therapeutic compounds. Compositions including resistance test vectors and host cells transformed with the resistance test vectors are provided.
The present invention provides methods for treating a flavivirus infection, including hepatitis C virus (HCV) infection, in an individual suffering from a flavivirus infection. In some embodiments, the methods involve administering to an individual in need thereof an effective amount of an agent that inhibits enzymatic activity of a membrane-bound α-glucosidase inhibitor. In other embodiments, the methods involve administering to an individual in need thereof effective amounts of an α-glucosidase inhibitor and at least one additional therapeutic agent.