Previous infection with Staphylococcus aureusstrains attenuated experimental encephalomyelitis

Thais Graziela Donegá França, Fernanda Chiuso-Minicucci, Sofia Fernanda Gonçalves Zorzella-Pezavento, Larissa Lumi Watanabe Ishikawa, Larissa Camargo da Rosa, Priscila Maria Colavite, Camila Marques, Maura Rosane Valério Ikoma, Maria de Lourdes Ribeiro de Souza da Cunha, Alexandrina Sartori

Bacterial superantigens are potent T cell activators that can activate T cells with specificity for antigens of the central nervous system (CNS). In this study, we compared the effect of two S. aureus strains on experimental autoimmune encephalomyelitis (EAE) development. C57BL/6 female mice were infected with S. aureus ATCC 51650, which produces toxic shock syndrome toxin 1 (TSST-1+) or S. aureus ATCC 43300, which does not produce toxins (TOX-). Three days later, the animals were subjected to EAE induction by immunization with myelin oligodendrocyte glycoprotein (MOG). The weight variation, disease incidence and clinical score were recorded daily. Cytokines and Foxp3+ regulatory T cells in the brain were evaluated during the acute disease phase. Cytokines and Foxp3+ regulatory T cells in the spleen and histopathological analysis of the CNS were assessed during the chronic stage.