Infections, Vaccines and Autoimmunity: A Multiple Sclerosis Perspective

Abstract

Background: Multiple sclerosis (MS) is a chronic neuroinflammatory and neurodegenerative disease that is associated with multiple environmental factors. Among suspected susceptibility events, studies have questioned the potential role of overt viral and bacterial infections, including the Epstein Bar virus (EBV) and human endogenous retroviruses (HERV). Furthermore, the fast development of immunomodulatory therapies further questions the efficacy of the standard immunization policies in MS patients. Topics reviewed: This narrative review will discuss the potential interplay between viral and bacterial infections and their treatment on MS susceptibility and disease progression. In addition, the review specifically discusses the interactions between MS pathophysiology and vaccination for hepatitis B, influenza, human papillomavirus, diphtheria, pertussis, and tetanus (DTP), and Bacillus Calmette-Guerin (BCG). Data regarding potential interaction between MS disease modifying treatment (DMT) and vaccine effectiveness is also reviewed. Moreover, HERV-targeted therapies such as GNbAC1 (temelimab), EBV-based vaccines for treatment of MS, and the current state regarding the development of T-cell and DNA vaccination are discussed. Lastly, a reviewing commentary on the recent 2019 American Academy of Neurology (AAN) practice recommendations regarding immunization and vaccine-preventable infections in the settings of MS is provided. Conclusion: There is currently no sufficient evidence to support associations between standard vaccination policies and increased risk of MS. MS patients treated with immunomodulatory therapies may have a lower benefit from viral and bacterial vaccination. Despite their historical underperformance, new efforts in creating MS-based vaccines are currently ongoing. MS vaccination programs follow the set back and slow recovery which is widely seen in other fields of medicine.

COVID-19 and Multiple Sclerosis: Predisposition and Precautions in Treatment

“…Microbial infections can act as triggers for inducing autoimmunity and clinical disease manifestations in genetically predisposed individuals [32][33][34][35]. Studies have suggested a robust relationship between viral infections and exacerbations of MS [36][37][38][39][40][41][42][43][44][45]. Based on the aforementioned studies, COVID-19 carries additional reasons for concern because of taking immunosuppressive therapies in MS patients [47,48] and also the fact that viral infections may contribute to MS exacerbation and relapses as an environmental factor [38,39].…”

Nano-based approaches in the development of antiviral agents and vaccines

“…VLPs are the most widely applied nanosystem for antiviral vaccines. Currently available HPV vaccines, such as Gardasil, Gardasil 9, and Cervarix, which effectively protect women from HPV infection, are all nano-based VLP vaccines [ 81 ]. A VLP vaccine against HEV, Hecolin, is also commercially available [ 82 ].…”

Do Vaccines Have a Role as a Cause of Autoimmune Neurological Syndromes?

“…For similarity with what has been shown for infections, it was thought that vaccines could also lead to demyelination. In some cases, a strict temporal relationship between vaccine administration and the development of CNS demyelinating syndromes has been reported, favoring the hypothesis that vaccine administration, despite being able to ensure protection against some infections, could be deleterious and cause clinical problems sometimes even more severe than the prevented disease (15). Most of the reported cases concerned hepatitis B vaccine (HBV) and human papillomavirus vaccine (HPV).…”