Development of hbv-and/or hdv-susceptible cells, cell lines and non-human animals

A method of producing a cell that is susceptible to HBV and/or HDV infection, wherein said method comprises the steps of

• providing a cell that is non-susceptible to HBV and/or HDV infection;
• and
• modifying, by homologous recombination, an endogenous gene of said cell corresponding to the human gene encoding SEQ ID NO:
• 1, so as to replace
• the amino acids corresponding to amino acids 194 to 197 of SEQ ID NO:
• 1 with amino acids 194 to 197 of SEQ ID NO:
• 1 or SEQ ID NO:5 and/or
• the amino acids corresponding to amino acids 156 to 162 of SEQ ID NO:
• 1 with amino acids 156 to 162 of SEQ ID NO:
• 1, SEQ ID NO:
• 4 or SEQ ID NO:
• 5.

A method that comprises the use of

• (a) an amino acid sequence represented by SEQ ID NO:1, or an amino acid sequence that is at least 90% identical to SEQ ID NO:
• 1, or
• (b) an amino acid sequence comprising
• SEQ ID NO:
• 2 or an amino acid sequence that is at least 90% identical to SEQ ID NO:
• 2, and
• an amino acid sequence having the general formula Pro-Tyr-X-Gly-Ile, wherein X is selected from Lys, Arg and Val
• as a receptor for HBV or HDV.