In MS patients, CSF and serum levels of TNF-α are elevated compared Natural Product Library with healthy subjects, and a rise in TNF-α in PBMCs has also been shown to precede clinical relapses 25, 42. TNF-α signaling through the neurotrophin receptor p55 in neurons and glia can mediate glutamate toxicity or lead to the activation of apoptotic signaling cascades (NF-κB, JNK, or p38 pathway) 42, 43. Notably, estradiol’s protective effect in EAE has been

attributed in part to its ability to inhibit the production of proinflammatory cytokines such as TNF-α from peripheral immune cells, and this has been shown to be mediated through ER-α 43, 44. Our results demonstrating an ER-β ligand-mediated R428 concentration reduction TNF-α in DC in the CNS in vivo, and in DC:TC cultures in vitro, which correlated with sparing of myelin and axons, together demonstrate a previously unknown immunomodulatory capacity for ER-β treatment. Notably, because ER-β is broadly expressed in the CNS on neurons, astrocytes, and oligodendrocytes, our findings do not preclude additional neuroprotective mechanisms as well. Nevertheless, our findings clearly support

the notion that ER-β ligand treatment should now be considered a potential strategy to attenuate DC function in the target organ of autoimmune demyelinating diseases. Female ER-β homozygous knockout mice were purchased from Taconic Farms (Germantown, NY, USA), and female WT C57BL/6 and B6.Cg-Tg (Thy1-YFP) Hydroxychloroquine 16Jrs/J mice were purchased from the Jackson Laboratory (Bar Harbor, ME, USA). Animals were maintained under standard conditions in a 12-h dark/light cycle with access to food and water ad libitum. All procedures were done in accordance with the guidelines of the National Institutes of Health and the Chancellor’s

Animal Research Committee of the University of California, Los Angeles Office for the Protection of Research Subjects. Animals were subcutaneously injected with myelin oligodendrocyte glycoprotein (MOG), amino acids 35–55 (200 μg/animal, American Peptides) emulsified in complete Freund’s adjuvant and supplemented with Mycobacterium tuberculosis H37Ra (200 μg/animal, Difco Laboratories) over four draining inguinal and axillary LN sites in a volume of 0.1 mL/mouse. Animals were either treated with vehicle consisting of 10% molecular-grade ethanol (EM Sciences) and 90% Miglylol 812N liquid oil (Sasol North America) or the ER-β ligand, Diarylproprionitrile (Tocris Biosciences) diluted with vehicle at a dose of 8 mg/kg/day for seven days before immunization or adoptive transfer of in vitro stimulated lymphocytes.