However, whether GA acts directly on the monocyte population or through promiscuous modulation of multiple APC subsets to induce type II suppressor function in vivo is yet to be determined. To expand our understanding of the suppressive mechanisms of GA and elucidate whether GA MDV3100 solubility dmso targets specific subsets of APC, we investigated the association between GA treatment and blood monocyte function. We found that following intravenous administration, GA directly and selectively targeted

blood monocytes in vivo without the requirement for MHC class II. GA+ monocytes exhibited enhanced suppression of T cell proliferation in vitro. Upon intravenous GA treatment, proliferation of myelin-specific T cells was also impaired in vivo. Interestingly, although see more subcutaneous GA treatment afforded protection from EAE, protection was associated with selective inhibition of IFN-γ production, rather than IL-17 or suppression of T cell proliferation. Our findings not only provide further examples of the mechanisms involved in GA-dependent suppression of autoimmune

reactivity but also illustrate that the different routes of GA administration engage different immunosuppressive pathways. Mice.  Breeding pairs of C57BL/6J (CD45.2+) mice were originally purchased from the Jackson Laboratory (Bar Harbor, ME, USA), and the congenic CD45.1+ mice (B6.SJLPtprca/Pepcb/BoyJ) were from the Animal Resource Centre (Canning Vale, WA, Australia). MHC class II–deficient B6Aa0/Aa0 mice were obtained from Dr H. Bluethmann (Hoffmann-La Roche, Basel, Switzerland). 2D2 mice (CD45.2+) expressing transgenic TCRs specific for

the MOG35–55 peptide (MEVGWYRSPFSRVVHLYRNGK) presented by IAb were obtained from Harvard Medical School (Boston, MA, USA) and derived as described [21] All mice were maintained at the Biomedical Research Unit, Malaghan Institute of Medical Research, Wellington, New Zealand. Experimental Demeclocycline protocols were approved by the Victoria University of Wellington Animal Ethics Committee and performed according to their guidelines. Sex- and age-matched mice were used between 8 and 12 weeks of age for all experiments. Immunizations and treatment.  Experimental autoimmune encephalomyelitis was induced by subcutaneous immunization with 50-μg MOG35–55 (synthesized by Mimotopes, Clayton, Vic., Australia) emulsified in complete Freund’s adjuvant (CFA) containing 500 μg heat-killed Mycobacterium tuberculosis, followed by intraperitoneal injections of 250-ng pertussis toxin 1 day after immunizations. Mice were treated with GA simultaneously for EAE induction according to Gilgun-Sherki et al. [22], by immunization with a single emulsion containing both MOG35–55 and 500 μg GA (Teva Pharmaceutical, Petach Tikva, Israel).