Long-Term Persistent Infection of Domestic Rabbits by the Human Foamy Virus

Human foamy virus (HFV) belongs to the spumaretrovirus group of the Retroviridae taxonomic family. Attempts to associate HFV or other foamy viruses to a specific pathology still remain unsuccessful. However, viral gene expression as well as tissue-specific tropism in anin vivocontext remain poorly analyzed. To address this issue, we have infected domestic rabbits with a single dose of HFV and followed them at the biological and molecular levels for 5 years. No apparent pathology was detectable in the infected animals which have developed a strong immunological response against major viral proteins. We found that HFV provirus in blood cells and several organs persisted predominantly in its defective form, ΔHFV, suggesting thatin vivoviral persistence could be related to homologous interference as was recently shownin vitro.This animal model might be useful for studying thein vivotargets of HFV and should also be convenient for testing therapeutic effects of anti-retroviral drugs.