Human endogenous retrovirus and Epstein-Barr virus: another piece to Multiple Sclerosis puzzle

Introduction: Multiple sclerosis (MS) is a disease that leads to a central nervous system (CNS) inflammatory lesions and demyelination. The current accepted hypothesis for the etiology of MS corresponds to an autoimmune process triggered by environmental and genetic factors. Also, it is noted that viruses play an important role in MS pathogenesis as the human endogenous retroviruses (HERVs) and Epstein-Barr virus (EBV). Those are believed to be intrinsically involved with the disease’s pathogenesis, stage and progression. Objectives: This abstract’s objective is to bring attention to the issue of MS correlation to EBV and HERV proteins. Methods: This work is a non-systematic review. All articles used were searched in the public databases PubMed, Medline, ScienceDirect, SciELO and Cochrane. The process of localizing these articles was done by searching for terms related to multiple sclerosis, HERV, EBV and selecting the most relevant articles available in English. Results: It has been shown that EBV possesses the ability to promote epigenetics alterations. In MS context, it was demonstrated that EBV infection induced HERV-W elements (syncytin-1 and MSRV) activation in astrocytes and blood cells through NF-kB pathway. Also it was demonstrated that MS patients possess higher levels of syncytin-1. Furthermore, HERV proteins may trigger both innate and adaptive immune responses. Conclusion: In conclusion, EBV’s epigenetic ability inducing HERV’s activation in a variety of cells may play a role in MS pathogenesis. This is a crucial piece in the disease’s puzzle, once there are new treatments for MS under development focusing specifically on HERV mechanism, such as monoclonal antibodies targeting MSRV-Env protein and antiretroviral therapy.