Abstract: The present invention relates to a method for efficiently infecting a small animal with hepatitis C virus. Specifically, the present invention relates to a method for infecting a small animal with hepatitis C virus, which comprises a step of administering RNA containing the genomic RNA of hepatitis C virus into the liver, or a step of administering to a small animal the culture supernatant of an animal cell having a vector that contains cDNA corresponding to the genomic RNA of hepatitis C virus introduced therein, and relates to a small animal infected with hepatitis C virus by these methods. The present invention further relates to a method for screening for remedies against hepatitis C virus-associated diseases, or substances that inhibit the growth of hepatitis C virus using the yield of the virus as an indicator.

Abstract: The present invention provides a gene encoding an RNA polymerase which plays an important role in the reproduction of hepatitis C virus, and a method of screening using this gene or this RNA polymerase protein, thereby allowing easy performance of screening for substances which inhibit the RNA polymerase playing an important role in HCV reproduction.

Abstract: The object of the present invention is to reproduce conditions where viral proteins can function along with the original life cycle of the viruses and to establish an expression system which can evaluate the function of viral proteins by a reporter gene without generating infectious viruses. The present invention provides an assay system comprising a vector containing DNA coding for RNA virus-derived RNA-dependent RNA polymerase and a vector containing a reporter gene expressed in the anti-sense direction.

Abstract: This invention provides a vector comprising cDNA encoding an RNA viral gene, characterized in that the vector is constructed such that both termini of the RNA viral gene can be transcribed precisely and uniformly. This vector is useful to elucidate the mechanisms of RNA virus replication and of the development of RNA virus infections, and to develop therapeutic agents and means of treatment, and so on.

Abstract: A hepatitis type C animal model into which cDNA derived from hepatitis C virus has been introduced. This animal model is useful for clarification of an onset mechanism of hepatitis C and as well as for development of means for treating the disease.

Abstract: Transgenic mice are described which serve as a model for Hepatitis C infection. The transgenic mice contain, in their germline and somatic cells, the Hepatitis C viral fragment CN2, N24 or CR under the control of a Cre-loxP switch-expression system. Administration of Cre to the mice results in a phenotype of increased serum GTP levels, emergence of acidophilic bodies in the liver, exfoliation of hepatic cells, hypertrophy and hyperplasia of Kupffer's cells, and conglomeration of lymphocytes.

Abstract: This invention relates to a DNA fragment comprising a base sequence encoding a non-A non-B hepatitis-specific antigen polypeptide, said base sequence being obtained using genetic engineering techniques from non-A non-B hepatitis virus RNA which is isolated directly from blood plasma from non-A non-B hepatitis patients, to an expression vector and a transformant for use in the expression of the DNA fragment, to a single strand DNA sequence for PCR primer, and to use of said polypeptide and said single strand DNA sequence in the detection of the non-A non-B hepatitis virus. The recombinant polypeptide and the single strand DNA sequence for PCR primer make it possible to detect the non-A non-B hepatitis virus with extremely high accuracy.

Abstract: This invention relates to a DNA fragment comprising a base sequence encoding a non-A non-B hepatitis-specific antigen polypeptide, said base sequence being obtained using genetic engineering techniques from non-A non-B hepatitis virus RNA which is isolated directly from blood plasma from non-A non-B hepatitis patients, to an expression vector and a transformant for use in the expression of the DNA fragment, to a single strand DNA sequence for PCR primer, and to use of said polypeptide and said single strand DNA sequence in the detection of the non-A non-B hepatitis virus. The recombinant polypeptide and the single strand DNA sequence for PCR primer make it possible to detect the non-A non-B hepatitis virus with extremely high accuracy.