First Author | Teige I | Year | 2003 |
Journal | J Immunol | Volume | 170 |
Issue | 9 | Pages | 4776-84 |
PubMed ID | 12707359 | Mgi Jnum | J:83021 |
Mgi Id | MGI:2656467 | Doi | 10.4049/jimmunol.170.9.4776 |
Citation | Teige I, et al. (2003) IFN-beta Gene Deletion Leads to Augmented and Chronic Demyelinating Experimental Autoimmune Encephalomyelitis. J Immunol 170(9):4776-84 |
abstractText | Since the basic mechanisms behind the beneficial effects of IFN-beta in multiple sclerosis (MS) patients are still obscure, here we have investigated the effects of IFN-beta gene disruption on the commonly used animal model for MS, experimental autoimmune encephalomyelitis (EAE). We show that IFN-beta knockout (KO) mice are more susceptible to EAE than their wild-type (wt) littermates; they develop more severe and chronic neurological symptoms with more extensive CNS inflammation and demyelination. However, there was no discrepancy observed between wt and KO mice regarding the capacity of T cells to proliferate or produce IFN-gamma in response to recall Ag. Consequently, we addressed the effect of IFN-beta on encephalitogenic T cell development and the disease initiation phase by passive transfer of autoreactive T cells from KO or wt littermates to both groups of mice. Interestingly, IFN-beta KO mice acquired a higher incidence and augmented EAE regardless of the source of T cells. This shows that the anti-inflammatory effect of endogenous IFN-beta is predominantly exerted on the effector phase of the disease. Histopathological investigations of CNS in the effector phase revealed an extensive microglia activation and TNF-alpha production in IFN-beta KO mice; this was virtually absent in wt littermates. This coincided with an increase in effector functions of T cells in IFN-beta KO mice, as measured by IFN-gamma and IL-4 production. We suggest that lack of endogenous IFN-beta in CNS leads to augmented microglia activation, resulting in a sustained inflammation, cytokine production, and tissue damage with consequent chronic neurological deficits. |