Differential Cytokine and Chemokine Production Characterizes Experimental Autoimmune Meningitis and Experimental Autoimmune Encephalomyelitis

After primary immunization with myelin/oligodendrocyte glycoprotein, CD28−/− mice developed experimental autoimmune meningitis (EAM) rather than experimental autoimmune encephalomyelitis (EAE). Cytokine and chemokine production in EAE and EAM were compared to understand the differences in disease phenotype. T cells from the central nervous system lesions of mice with either EAE or EAM expressed intracellular TNF-α. Splenic T cells from mice with EAM produced TNF-α and IL-6 but no IL-2. Conversely, EAE-derived splenic T cells produced TNF-α and IL-2 but no IL-6. Altered T cell differentiation in EAM was not due to a Th1 to Th2 shift, because equivalent amounts of T cell IFN-γ mRNA were produced in both diseases. Neutrophils also produced inflammatory mediators such as TNF-α and IL-6 in EAM. Autocrine production of MIP-2 mRNA was observed in neutrophils from mice with EAM but not EAE. Therefore, distinct patterns of cytokines and chemokines distinguish EAE and EAM.