Role of inactivated influenza vaccine in regulation of autoimmune processes in experimental autoimmune encephalomyelitis

Abstract

Experimental autoimmune encephalomyelitis (EAE) is characterized by appearance of anti-myelin autoantibodies in the blood and with the increased expression of MHC (major histocompatibility complex) class I and II antigens in the brain tissue. Although there is an evidence of possible linkage between influenza vaccination and development of autoimmune processes, the precise mechanisms of action of this vaccine on EAE-induction is still unclear. In this study, effects of influenza vaccine on clinical sign, antimyelin antibody titer in the blood by ELISA test and expression of MHC class I and II molecules immunohistochemistry were examined in the brain of C57BL mice with EAE. EAE was induced by MOG 35-55 protein in 16 of 32 mice. Influenza split vaccine was administered to eight MOG-induced EAE mice and to eight previously nontreated mice. A significant increase of anti-influenza antibody was detected in vaccinated mice compared to nontreated mice. Also, significant increase of antimyelin antibodies was detected in mice with EAE compared to vaccinated group without EAE and control group, respectively. In EAE-influenza vaccinated mice, a mild but not significant increase of antimyelin antibodies was detected, compared to EAE mice. High expression of MHC-II and mild expression of MHC-I were detected in the brain of mice with EAE. No expressions were detected in vaccinated and normal intact brains. Similar staining was found between EAE-vaccinated and EAE group in both MHC-I and MHC-II expression. The results obtained show that influenza vaccine has no significant influence on EAE induction and severity of autoimmune processes.

Vaccination and autoimmunity: Influenza vaccination and association with multiple sclerosis

“…No difference was found between influenza vaccine vaccinated vs intact groups and a positive correlation was found between anti-MOG antibody titer and the development of the EAE clinical signs. The overall data presented in this study indicate that influenza vaccine has no effect on production of autoantibodies and development of clinical signs 76 . A number of cohort studies demonstrated a transient change in autoantibody production, with presumably no clinical significance, after influenza vaccination in apparently healthy participants 83,84 .…”

“…He also argues against a general immune stimulation by influenza vaccination since no increase of myelin protein-reactive T-cells was observed after immunization. The overall data presented in this study support the effectiveness and safety of influenza vaccination in the patients with MS. Our group was reported that antiinfluenza antibody titers in healthy vaccinated mice and in MOG induced EAE-vaccinated mice, 4 weeks after vaccina-tion with inactivated influenza vaccine (split virion), was significantly higher compared to the unvaccinated control groups, indicating long-lasting antibody response as well as preserved immune response in MOG induced EAE mice 76 . A possible role of several viruses, including influenza A virus, was investigated in a case-control study in 152 children with MS and a significantly higher concentration of antibodies was found in the MS patients comparing with controls.…”

Encefalomielitis aguda diseminada grave: Comunicación de un caso asociado a infección por virus parainfluenza 3

“…La incidencia de complicaciones neurológicas graves post vacuna anti-influenza, incluyendo la EMAD, es muy baja y ha sido estimada en menos de 0,01% en un estudio prospectivo de 49.138 inmunizaciones en una población militar en Francia, lo que nuevamente debilita su rol causal 30 . Por otra parte, un estudio experimental reciente no mostró diferencias significativas en los títulos de anticuerpos antimielina en el grupo vacunado contra influenza al compararlo con controles 31 , lo que disminuye su plausibilidad biológica. Algunos han considerado que debe existir una relación temporal clara entre la inmunización y la aparición del cuadro de EMAD y que la limita a un plazo de una a tres semanas (máximo un mes).…”