Avaliação de duas diferentes concentrações de glicoproteína mielínica de oligodendrócitos no modelo de encefalomielite autoimune experimental

Abstract

Multiple sclerosis (MS) is an inflammatory autoimmune disease of central nervous system (CNS) that causes demyelination and neurological deficit. The experimental autoimmune encephalomyelitis (EAE) is the most common model for study this disease. The EAE can be induced by different protocols and the score of the disease is related to the genetic background of the animals, the concentration of antigen and the way of induction, reproducing the heterogeneity of the MS. Thus, due to the diversity of EAE induction, different factors related to immune response are still unclear. The aim of this study was evaluate the difference between two antigen concentrations in the development of EAE and the parameters of immune response. The EAE was induced in C57BL/6 female mice with the myelin oligodendrocyte glycoprotein (MOG35-55) in two different concentrations (100 or 300μg of MOG35-55), but keeping the same concentrations of Mycobacterium tuberculosis (4 mg/mL) and pertussis toxin (300 ng). The disease clinical signs were followed until the 58th day after induction in both protocols, and the immunological parameters, such as cellular infiltrate at brain and levels of cytokines and chemokines at CNS and lymph nodes, were evaluated at 7th, 10th, 14th, 21st and 58th days post induction. In relation to the clinical score, were not observed significant differences between the different protocols, however the cytokines, chemokines and cellular infiltrate profile at brain showed interesting results. The release of Th1 and Th17 cytokines and the CCL5 and CCL20 chemokines at CNS occurred early and more intense at 100μg MOG35-55 group, in accordance with the earlier and intense cellular infiltrate than 300μg MOG35- 55 group. In conclusion, the results suggest that only the differences in the MOG35-55 concentration at induction, is not capable of induce different clinical signs of EAE and that the 300 μg of MOG35-55 seems to promote a regulatory or tolerance mechanism that deserves further studies.