Transspecies Transmission of the Endogenous Koala Retrovirus
Uwe Fiebig,1 Manuel Garcia Hartmann,2 Norbert Bannert,1 Reinhard Kurth,1 and Joachim Denner1*
Robert Koch Institute, 13353 Berlin,1
Zoo Duisburg, 47058 Duisburg,2 Germany
The koala retrovirus (KoRV) is a gammaretrovirus closely related to the gibbon ape leukemia virus and induces leukemias and immune deﬁciencies associated with opportunistic infections, such as chlamydiosis. HerewecharacterizeaKoRVnewlyisolatedfromananimalinaGermanzooandshowinfectionofhumanand rat cell lines in vitro and of rats in vivo, using immunological and PCR methods for virus detection. The KoRV transmembrane envelope protein (p15E) was cloned and expressed, and p15E-speciﬁc neutralizing antibodies able to prevent virus infection in vitro were developed. Finally, evidence for immunosuppressive properties of the KoRV was obtained.