The invention provides an animal model for hepatocellular carcinoma and uses thereof. The genome of the animal model includes a hepatitis B virus genome and a single set of endogenous miR-122 that is partially deleted. Due to the early and high incidence of spontaneous hepatocellular carcinoma in the animal model and its abnormal fat metabolism, the animal model can be used to screen candidate agents for prevention or treatment of hepatitis B virus and hepatocellular carcinoma or other diseases or to develop uses for diagnosis and prediction of hepatocellular carcinoma.

Provided are polynucleotides containing a modified PRE having a variant X gene that includes one or more stop codons not present in an unmodified, such as wild-type, hepatitis X gene. Also provided are polynucleotides containing a modified PRE having a variant X gene that includes one or more degradation sequences not present in an unmodified, such as wild-type, hepatitis X gene. The modified PRE can be operably linked to a nucleic acid encoding a recombinant protein. Also provided are expression cassettes, viral vectors and cells containing the polynucleotides, and compositions and methods of use thereof.

The present disclosure generally relates to hepadnavirus core antigens in which one or more endogenous b cell epitopes have been effectively removed. More specifically, the present disclosure relates to rodent hepadnavirus cores modified to diminish the antibody response to the core so as to enhance the antibody response to heterologous polypeptides included therein.

The present disclosure provides immunogens, immunogenic compositions, vaccines based on neutralizing epitopes from lethal factor peptide (LF) and loop neutralizing determinant (LND) of protective antigen, and methods of using thereof for treating and preventing infection and disease caused by Bacillus anthracis.

The invention provides an animal model for hepatocellular carcinoma and uses thereof. The genome of the animal model includes a hepatitis B virus genome and a single set of endogenous miR-122 that is partially deleted. Due to the early and high incidence of spontaneous hepatocellular carcinoma in the animal model and its abnormal fat metabolism, the animal model can be used to screen candidate agents for prevention or treatment of hepatitis B virus and hepatocellular carcinoma or other diseases or to develop uses for diagnosis and prediction of hepatocellular carcinoma.