Intraspecies transmission of L-type-like bovine spongiform encephalopathy detected in Japan


Hiroyuki Okada, Prion Disease Research Center, National Institute of Animal Health, Kannonndai 3-1-5, Tsukuba, Ibaraki 305-0856, Japan. Tel & fax: +81-29-838-7757; email:


It has been assumed that the agent causing BSE in cattle is a uniform strain (classical BSE); however, different neuropathological and molecular phenotypes of BSE (atypical BSE) have been recently reported. We demonstrated the successful transmission of L-type-like atypical BSE detected in Japan (BSE/JP24 isolate) to cattle. Based on the incubation period, neuropathological hallmarks, and molecular properties of the abnormal host prion protein, the characteristics of BSE/JP24 prion were apparently distinguishable from the classical BSE prion and closely resemble those of bovine amyloidotic spongiform encephalopathy prion detected in Italy.