Differential tumor necrosis factor alpha expression by astrocytes from experimental allergic encephalomyelitis-susceptible and -resistant rat strains

We have demonstrated that astrocytes from EAE-susceptible and -resistant rat strains differ in their ability to express TNF-ca mRNA and protein. These differences are especially pronounced for IFN-y priming ofTNF-ca gene expression. Endogenous levels of PGE2, a known inhibitor of TNF-a, did not differ in astrocytes from the two strains. Differential TNF-a expression is selective for the astrocyte, as both peritoneal macrophages and microglia from Lewis and BN rats express TNF-ci protein in response to all of the stimuli used. In addition, IL6 production by Lewis and BN astrocytes is comparable in response to induction by LPS, IFN-y, and IWO, indicating that cytokine production in general is not altered . Taken together, these results indicate that the differential expression ofTNF-a mRNA and protein in Lewis and BN astrocytes may involve transcriptional and/or post-transcriptional events .