Targeting pathogenic effects of human endogenous retroviruses

The sequencing of the human genome revealed that nearly one-half of the genome is composed of repeated or retrotransposable elements. Among them, human endogenous retroviruses (HERVs) represent more than 8% of the human genome and result from integration of exogenous retroviruses that have infected the germline of their host during the primate evolution.

HERVs appear to have a critical significance in physiology and in diseases, at the crossroads of genetics, virology and physiopathology.

A human endogenous retrovirus, the MS associated retrovirus (MSRV), a member of the HERV-W family, had been initially isolated in cell cultures from patients affected with MS. MSRV is normally latent in the genome of individuals, but when activated by certain co-factors, it can be reactivated and express an envelope protein (HERV-W/ENV). This appears to be a major triggering and aggravating factor in the development and progression of MS. Depending on environmental co-factors, HERV-W MSRV could be involved in both Multiple Sclerosis and Schizophrenia.