Disclosed herein are methods for producing virus-infected cell lines or animal models, wherein an enveloped virus including a lipid bilayer is mixed with a bile acid or a bile acid derivative, which allows the lipid bilayer to be replaced with a lipid bilayer derived from a target animal. Also disclosed herein are the virus-infected cell lines or animal models so produced and methods of screening a therapeutic candidate for a viral disease using the same.

A cell comprising: a nucleotide sequence encoding a Hepatitis B Virus (HBV) operably linked to a promoter; two nucleotide sequences each encoding an isoform of HNF4α; and a nucleotide sequence encoding a repressor of HBV transcription, wherein said nucleotide sequence is mutated to decrease or silence expression of the repressor.

Disclosed is a method for producing an antibody reagent for detecting a test substance in a sample by an immune complex transfer method. The method comprises the steps of: bringing an antibody solution comprising a labeled antibody capable of binding to the test substance into contact with a solid phase used in the immune complex transfer method; and separating the solid phase and the antibody solution to prepare the antibody reagent from the antibody solution.

The present invention relates to a method of diagnosing and/or monitoring of virus infection and/or response to vaccination by generating a profile of a virus-specific T cell response that can (i) discriminate between virus infected and uninfected individuals, (ii) determine the effect of vaccination on T cell response, and (iii) determine the effect of viral variants on T cell response. More particularly, the described virus-specific T cell profiling is based on the detection of activated antigen-specific T lymphocytes responding to pools of selected short peptides from virus proteins. These peptide sequences have been selected for their immunogenicity. The profiling is typically performed using ELISPOT, but may also be performed using other techniques such as qPCR, more particularly direct qPCR. The present invention also includes kits for use in the methods of the invention.

The present invention relates to a porcine sodium taurocholate cotransporter polypeptide (NTCP) mutein, which has been modified at sequence positions 157-167 with the human sequence. This NTCP mutein renders a host cell and a transgenic animal susceptible for an infection with hepatitis B virus (HBV) and/or hepatitis D virus (HDV). The present invention further relates to a nucleic acid and a vector comprising the NTCP mutein of the invention. Also presented are methods for producing cells and transgenic animals, which are susceptible to HBV and/or HDV as well as uses of the NTCP mutein screening for compounds or rendering a cell susceptible for an infection with HBV and/or HDV. Additionally provided is a method for identifying a compound, which is useful in the prevention and/or treatment of HBV and/or HDV infection.

A magnetic digital microfluidic apparatus for manipulating a liquid droplet containing magnetic particles using a magnetic force, the apparatus comprising: a hydrophobic surface on which the liquid droplet containing magnetic particles can be moved using the magnetic force; and at least one surface energy trap provided to retain at least a portion of the liquid droplet thereon, the at least one surface energy trap comprising a layer of polydopamine. A method of magnetic digital microfluidic manipulation, the method comprising the steps of: a) contacting a liquid droplet on a hydrophobic surface with a polydopamine surface energy trap, the liquid droplet containing magnetic particles; b) retaining at least a portion of the liquid droplet on the surface energy trap; and c) moving at least the magnetic particles with a magnetic force.

Hepatitis F virus (HEV) is responsible for over 50% of acute viral hepatitis cases worldwide. The inventors have now identified the precise sequence of infectious particle-associated ORF2 capsid protein. Strikingly, their analyses revealed that in infected patients, HEV produces three forms of the ORF2 capsid protein: ORF2i, ORF2g and ORF2c. The ORF2i protein is associated with infectious particles whereas ORF2g and ORF2c proteins are massively produced glycoproteins that are not associated with infectious particles and arc the major antigens present in HEV-infected patient sera. Accordingly, the ORF2i and ORF2g proteins are thus the subject matter of the present invention as well as antibodies specific for the proteins and diagnostic assays (e.g. ELISA) for the diagnosis of Hepatitis E virus infection.

Provided herein are, inter alia, antibodies, antigen-binding antibody fragments, cells, polynucleotides, compositions, kits, and methods relating to the detection of HBV protein X (HBx), e.g., in vitro and in vivo. Included are antibodies and fragments thereof that bind HBx, as well as kits, cells, and compositions comprising such antibodies and fragments.

This disclosure provides a multimeric hepatitis B virus (HBV) protein binding molecule, e.g., a dimeric IgA or a pentameric or hexameric IgM binding molecule, comprising at least two bivalent binding units, or variants or fragments thereof, each comprising at least two antibody heavy chain constant regions or fragments thereof, wherein each heavy chain constant region or fragment thereof is associated with an HBV antigen binding domain. The disclosure also provides compositions comprising the multimeric binding molecules, polynucleotides encoding the multimeric binding molecules, and methods to make and use the multimeric binding molecules.

Hepatitis E virus (HEV) is responsible for over 50% of acute viral hepatitis cases worldwide. The inventors have now identified the precise sequence of infectious particle-associated ORF2 capsid protein. Strikingly, their analyses revealed that in infected patients, HEV produces three forms of the ORF2 capsid protein: ORF2i, ORF2g and ORF2c. The ORF2i protein is associated with infectious particles whereas ORF2g and ORF2c proteins are massively produced glycoproteins that are not associated with infectious particles and are the major antigens present in HEV-infected patient sera. Accordingly, the ORF2i and ORF2g proteins are thus the subject matter of the present invention as well as antibodies specific for the proteins and diagnostic assays (e.g. ELISA) for the diagnosis of Hepatitis E virus infection.