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 exp erimental autoimmune encephalomyelitis (EAE). Cytokine and chemokine produc tion in EAE and EAM were compared to understand the differences in disease phenotype. T cells from the central nervous system lesions of mice with eit her EAE or EAM expressed intracellular TNF-alpha. Splenic T cells from mice with EAM produced TNF-alpha and IL-6 but no IL-2. Conversely, EAE-derived splenic T cells produced TNF-alpha and IL-2 but no IL-6. Altered T cell dif ferentiation in EAM was not due to a Th1 to Th2 shift, because equivalent a mounts of T cell IFN-gamma mRNA were produced in both diseases. Neutrophils also produced inflammatory mediators such as TNF-alpha and IL-6 in EAM. Au tocrine production of MIP-8 mRNA was observed in neutrophils from mice with EAM but not EAE. Therefore, distinct patterns of cytokines and chemokines distinguish EAE and EAM. (C) 2000 Academic Press.