MedicalResearch.com Interview with:
Prof. Dr. Patrick Küry
Dept. of Neurology Heinrich-Heine-University
MedicalResearch.com: What is the background for this study? How do these viruses in our DNA differ from others such as the herpes family of viruses?
Response: The background of our current two published studies is elucidating the role of endogenous retroviruses such as the HERV-W in contributing to neurological disease initiation and progression. Our new paper in PNAS (Kremer et al., PNAS 2019) describes a novel axon damage scenario for Multiple Sclerosis (MS) in which a “toxic” protein called ENV from HERV-W instructs so called microglial cells in the human brain to attack and damage myelinated axons.
Our second review article (Gruchot et al., Front Genet 2019) summarizes currently known effects on endogenous retroviruses exerted towards neural cells, that means cells other than the infiltrating immune cells. There is currently a shift of attention and research in the MS field in that resident neural cells such as oligodendrocytes, precursor cells, stem cells and microglial cells and their reactions are intensively investigated.
HERVs are evolutionary acquired retroviruses (RNA viruses able to integrate into host DNA via reverse transcription from RNA to DNA) that were collected during evolution by our ancestors. Some of them remained in our genome (8% of our genome is HERV related) and in most cases appear to be non-functional, mutated or genetically silenced. A few of them, as for example HERV-W in MS or HERV-K in ALS, can apparently be activated, woken up so to say, and one of the mechanisms leading to activation might be an infection by Herpesviruses. Note that herpesviruses such as for example the Epstein Bar Virus (EBV) are long known suspected triggers of MS, however, a direct correlation could never be demonstrated. HERVs such as HERV-W might therefore constitute the missing link.