Abstract: According to the present invention, immortalized cells derived from porcine kidney macrophages are found to have high infection susceptibility to various African swlne fever virus strains. As a result, using the cells, it is possible to proliferate the virus and furthermore produce and detect the virus.

Abstract: A method for efficiently amplifying abnormal prion protein (PrPSc) derived from bovine spongiform encephalopathy (BSE) is provided. Ultimately, the invention aims at eradicating the transmission of a prion disease by detecting a BSE-infected cow early and developing a method for inactivating prions and permitting early examination of prion inactivation. Provided is a method for efficiently amplifying PrPSc derived from BSE, wherein the method is based on a PMCA (protein misfolding cyclic amplification) method in which normal prion protein (PrPC) is used as a source and PrPSc is used as a seed, and PrPSc derived from BSE is amplified by stir-mixing, incubating, and sonicating both the PrPC and the PrPSc repeatedly, and wherein the method includes performing stir-mixing-incubation-sonication in the presence of a polysaccharide sulfate.