Anti-Inflammatory Activities of Stilbene Analogs for Targeting Autoimmune Diseases

S124 chimeric Btk-Itk DT40 line is inhibited by an Itk-specific kinase inhibitor. We demonstrate that potency and selectivity of inhibitors of Itk and Btk can be assessed in this FLIPR cell-based assay.

Abstracts Center, Johns Hopkins School of Medicine, Baltimore, MD, Rameeza Allie, Research Specialist, Department of Neurology, Johns Hopkins School of Medicine Baltimore, MD, Peter Calabresi, Associate Professor, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD

doi:10.1016/j.clim.2007.03.529

Sa.143 Anti-Inflammatory Activities of Stilbene Analogs for Targeting Autoimmune Diseases Liren Tang, Scientist, Welichem Biotech Inc., Burnaby, BC, Canada, Genhui Chen, Celestial Pharmaceuticals Ltd, Shenzhen, China, Bin Li, Scientist, Welichem Biotech Inc., Burnaby, BC, Canada, Quanhai Liu, Professor, Department of Pharmacology, Shanghai Instititue of Pharmaceutical Industry, Shanghai, China, Michael Lyle, Postdoctoral Fellow, Welichem Biotech Inc., Burnaby, BC, Canada, John Webster, Professor and CSO, Welichem Biotech Inc., Simon Fraser University, Burnaby, BC, Canada Certain species of symbiotic bacteria (Enterobacteriaceae), when released into an insect by their nematode vector, released metabolites that modulate the insect’s innate immune response. These metabolites (stilbene analogs, in the WBI-1000 series) possess unique antiinflammatory properties. In general, they are weakly cytotoxic to mammalian cells, being more active on activated than on quiescent T cells or other normal cells. When tested in vitro, the WBI-1000 series selectively inhibited IL-2 and IFN-γ production in human T cells, and significantly inhibited TNF-α production in mice, but IL-4 was not affected. As well, they significantly inhibited T cell migration towards LTB4 in vitro. When topically applied in the TPA-induced ear edema mouse model, WBI-1000 compounds significantly reduced both skin redness and thickness. To further explore the clinical applications of these compounds one of them, WBI-1001 was tested for its efficacy on different animal models for autoimmune diseases. WBI1001 showed dose-related efficacy in both the vaginal mucosa and mouse tail models for psoriasis as a topical treatment, significant clinical improvement in dextran sodium sulphate (DSS)-induced inflammatory bowel disease (IBD) in mice and decreased inflammation-induced arthritis in rats when compared with indomathecin. In conclusion, due to its unique anti-inflammatory properties, including selectivity on activated T cells, strong inhibition of proinflammatory cytokines and T cell migration, the WBI-1000 series of compounds could be developed into effective, novel treatment modalities for autoimmune diseases. doi:10.1016/j.clim.2007.03.551

Sa.145 Functional Knockout of Kv1.3 Channels Suppresses Effector Memory Phenotype Acquisition in Dominant Negative Kv1.3-expressing Human CD4+ T Cells Lina Hu, Research Associate, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, Katharine Whartenby, Assistant Professor, Sidney Kimmel Cancer

Activated effector memory T cells (TEM) that highly express the voltage-gated potassium channel Kv1.3 have the potential of migrating to the CNS and are hypothesized to play a pathogenic role in multiple sclerosis (MS). The pharmacological effects of Kv1.3 channel blockade on TEM cell activation and proliferation are well documented. However, the functional relevance of Kv1.3 in the homeostatic maintenance of TEM is poorly understood. Herein, using a system in which Kv1.3-channel function was blocked by transduction of CD4+ T cells with a GFP-tagged, lentiviral vector expressing dominant-negative Kv1.x sequence, we studied the kinetic changes in TEM subset within dominant negative Kv1.3-expressing CD4+ T cells following anti-CD3/CD28 stimulation. The interference of endogenous Kv1.3 by misexpression of dominant-negative Kv1.x markedly attenuated the wild-type current. Analysis of GFP expression in CD4+ T cell subsets demonstrated that while a substantial reservoir of TCM was maintained, TEM cells expressing the dominant-negative Kv1.3 product were significantly less abundant than that infected with GFP control viruses at 2, 3 and 4 weeks after transduction. In contrast, the ratio between TEM and TCM cells in GFP control transfected cells is strongly biased toward the TEM. Thus, the generation and maintenance of TEM cells are markedly impaired by the inactivation of Kv1.3 channel function. These results offer new insights into the functional dependence of TEM cells on Kv1.3, and have important clinical implications for using Kv1.3 blockers to prevent the generation of TEM cells, thereby abrogating the pathologic consequences of this subset in autoimmune diseases, such as MS. doi:10.1016/j.clim.2007.03.532

Sa.146 Tim-4 Expressed on Antigen-presenting Cells Induces T Cell Expansion and Survival Roselynn Rodriguez Manzanet, Graduate Student, Brigham and Women’s Hospital, Boston, MA, Jennifer Hartt-Meyers, Post doctoral Fellow, LIR/NIAID/NIH, Bethesda, MD, Jacqueline Slavik, Administrative Director, Brigham and Women’s Hospital, Biomedical Research Institute, Boston, MA, Valerie Dardalhon, Post doctoral Fellow, Brigham and Women’s Hospital, Department of Neurology, Boston, MA, Nasim Kassam, Research specialist, Brigham and Women’s Hospital, Department of Neurology, Boston, MA, Edward A. Greenfield, Consultant, Brigham and Women’s Hospital, Department of Neurology, Boston, MA, Raymond A. Sobel, Professor, Stanford School of Medicine, Department of Pathology, Palo Alto, CA, Terry B. Strom, Physician Professor, Beth Israel Deaconess Medical Center, Boston, MA, David A. Hafler, Professor, Brigham and Women’s Hospital, Department of Neurology, Boston, MA, Vijay K. Kuchroo, Professor, Brigham and Women’s Hospital, Department of Neurology, Boston, MA