First Author | Klotz L | Year | 2016 |
Journal | Proc Natl Acad Sci U S A | Volume | 113 |
Issue | 41 | Pages | E6182-E6191 |
PubMed ID | 27671636 | Mgi Jnum | J:238505 |
Mgi Id | MGI:5822953 | Doi | 10.1073/pnas.1601350113 |
Citation | Klotz L, et al. (2016) B7-H1 shapes T-cell-mediated brain endothelial cell dysfunction and regional encephalitogenicity in spontaneous CNS autoimmunity. Proc Natl Acad Sci U S A 113(41):E6182-E6191 |
abstractText | Molecular mechanisms that determine lesion localization or phenotype variation in multiple sclerosis are mostly unidentified. Although transmigration of activated encephalitogenic T cells across the blood-brain barrier (BBB) is a crucial step in the disease pathogenesis of CNS autoimmunity, the consequences on brain endothelial barrier integrity upon interaction with such T cells and subsequent lesion formation and distribution are largely unknown. We made use of a transgenic spontaneous mouse model of CNS autoimmunity characterized by inflammatory demyelinating lesions confined to optic nerves and spinal cord (OSE mice). Genetic ablation of a single immune-regulatory molecule in this model [i.e., B7-homolog 1 (B7-H1, PD-L1)] not only significantly increased incidence of spontaneous CNS autoimmunity and aggravated disease course, especially in the later stages of disease, but also importantly resulted in encephalitogenic T-cell infiltration and lesion formation in normally unaffected brain regions, such as the cerebrum and cerebellum. Interestingly, B7-H1 ablation on myelin oligodendrocyte glycoprotein-specific CD4+ T cells, but not on antigen-presenting cells, amplified T-cell effector functions, such as IFN-gamma and granzyme B production. Therefore, these T cells were rendered more capable of eliciting cell contact-dependent brain endothelial cell dysfunction and increased barrier permeability in an in vitro model of the BBB. Our findings suggest that a single immune-regulatory molecule on T cells can be ultimately responsible for localized BBB breakdown, and thus substantial changes in lesion topography in the context of CNS autoimmunity. |