e. Toxoplasma encephalitis [23, 36]. Consistently, blocking NF-κB signaling, which is required for astrocyte activation in EAE, by tissue-specific ablation of key signaling molecules including NEMO, IKK2, and
Act1 in the CNS impaired astrocytic production of inflammatory cytokines and chemokines ameliorating EAE as evidenced by decreased leukocyte infiltration and reduced demyelination [5, 37, 38]. Interestingly, in sharp contrast to the proinflammatory function of most astrocyte-derived chemokines, CXCL12, which is upregulated in the CNS of MS patients, particularly produced by astrocytes, suppressed ongoing EAE by redirecting the polarization of effector Th1 cells into IL10-producing Treg cells [39]. Collectively, the present study extends Selleck Enzalutamide the in vivo Selleckchem Sotrastaurin function of astrocytes and illustrates that astrocytes also confer protection against EAE by the
FasL-dependent apoptotic elimination of activated CD25+ Foxp3− and GM-CSF-producing CD4+ T cells and the concomitant inhibition of proinflammatory cytokine production. Thus, augmentation of astrocytic FasL may provide a favorable strategy for treatment of clinically active MS. GFAP-Cre+/− FasLfl/fl mice were generated by crossing C57BL/6 GFAP-Cre transgenic mice [40] with C57BL/6 FasLfl/fl mice [41] and the colony was maintained by breeding of GFAP-Cre+/− FasLfl/fl mice with GFAP-Cre−/− FasLfl/fl mice. Genotyping of offsprings was carried out by PCR of tail DNA with primers targeting GFAP-Cre and FasLfl/fl. Deletion of FasL was analyzed by PCR in various organs and cell types with Del-FasL primers (5′-GTACTTCTTCTGATAAGGACC-3′ Fluorometholone Acetate and 5′-GGAGTTGAACGAGTAGCCTC-3′). C57BL/6 WT mice were obtained from Harlan (Borchen, Germany). Animal care and experimental procedures were performed according to European regulations and approved by state authorities (Landesverwaltungsamt Halle, Germany; IMMB/G/02–994/10). MOG35–55 (MEVGWYRSPFSRVVHLYRNGK) was purchased from JPT (Berlin, Germany). Active EAE was induced in 8- to 12-week-old
mice by s.c. immunization with 200 μg of MOG35–55 emulsified in complete Freund’s adjuvant (Sigma, Taufkirchen, Germany) supplemented with 800 μg of killed Mycobacterium tuberculosis (Sigma). In addition, mice also received two i.p. injections of 200 ng pertussis toxin (Sigma), dissolved in 200 μL PBS, at the time of immunization as well as 48 h thereafter. Clinical signs of EAE were monitored daily and scored according to a scale of severity from 0 to 5 as described previously [23]. Daily clinical scores were calculated as the average of all individual disease scores within each group. Leukocytes were isolated from the spinal cord and stained for CD4+ T cells, CD8+ T cells, and CD45high inflammatory leukocytes as described before [42].