4th conference on Cytokines & Inflammation
|Event Date/Time: Jan 30, 2006||End Date/Time: Jan 31, 2006|
|Registration Date: Jan 31, 2006|
|Early Registration Date: Dec 30, 2005|
|Abstract Submission Date: Dec 30, 2005|
7:00 Breakfast and Registration
7:50 Opening Remarks
Session I: Basic Cytokine Studies
8:00 Role of new members of the IL-1 Ligand Family in Inflammation
Hal Blumberg, Amgen
The IL-1 family members IL-1a, IL-1B, and IL-18 are potent inflammatory cytokines that require heterodimeric IL-1R complexes, and are regulated by soluble antagonists. Recently, several novel IL-1 family members have been identified. Keratinocyte-driven expression of one of these members, IL-1F6, results in profound skin alterations that are dependent upon IL-1Rrp2 and IL-1RAcP. Strikingly, this phenotype is exacerbated in mice lacking a related IL-1 family member, IL-1F5. In summary, dysregulated expression of novel agonist and antagonist members of the IL-1 family can promote cutaneous inflammation and reveals potentially novel targets for the treatment of human inflammatory skin disorders.
8:30 IL-7 Signals Survival and Proliferation of T Cells
Scott Durum, NCI, FCRF, NIH
IL-7 is required by T cells at two stages, first as immature thymocytes, then later as mature T cells in peripheral lymphoid organs. Part of the requirement for IL-7 is to block apoptosis. We observed that this anti-apoptotic effect is partly achieved by inducing synthesis of Bcl-2, which protects mitochondria. IL-7 also protects the T cell from activation of the death proteins Bax, Bad and Bim which are posttranslationally activated by different mechanisms, to be discussed. A second requirement for IL-7 is to induce cell division which we observe occurs by two mechanisms that relieve G1 arrest. One cell cycle mechanism occurs through protecting the phosphatase Cdc25a from proteosomal degradation via a novel pathway to be discussed. Cdc25a removes an inhibitory phosphate from Cdk2, resulting in phosphorylation of Rb and entry into S phase. A second mechanism is by inducing proteosomal degradation of p27, an inhibitor of Cdk4; this occurs through a novel mechanism to be discussed. Because we observed that several other cytokine receptors, in addition to IL-7 receptor, can also induce cell survival and proliferation by similar pathways, we asked whether the IL-7 receptor intracellular domain delivers unique signals in T cell development. We observed that the IL-9 receptor intracellular domain can replace that of the IL-7 receptor in development of ab T cells. This suggests that the survival and proliferative functions of IL-7 receptor are not unique, although we do not understand them completely. However IL-7 also induces rearrangement of the TCRg locus and development of gd T cells, and this activity could not be replaced by IL-9 receptor suggesting that IL-7 receptor also delivers unique signals.
9:00 Shared Use of the IL-10 Receptor-2 Chain by Class-2 Cytokines
Ray Donnelly, FDA
9:30 Thereapeutic Approaches to Cytokine Modulation through Activation and Inhibition of Toll-like Receptors
John Carulli, Ph.D., Principal Scientist, Biogen Idec
10:00 Refreshment Break
10:30 In Vivo Evaluation of Inflammatory Targets in the post-genomic Era
Tamas Oravecz, Lexicon Genetics, Inc.
The sequencing of the human and mouse genomes is providing an unprecedented opportunity to better understand and treat human disease. To realize this goal, efficient methods are required to examine gene function in the context of the mammalian organism, and to identify novel therapeutic targets. Knockout mouse technology has proven to be a very effective method for modeling drug efficacy in inflammatory diseases. An examination of the targets of the best-selling anti-inflammatory drugs and pharmaceutical pipelines reveals a strong correlation between the knockout phenotype and the efficacy and/or side-effects of drugs that modulate that specific target. Lexicon Genetics has perfected systems and infrastructure for the generation and comprehensive phenotypic screen of mutant mice at a rate of twenty novel mutant lines per week. This mammalian genetic screen has been specifically engineered to reveal those genes that encode control points in physiology that may be used to treat major disease processes, including inflammation.
11:00 Velocimmune Mouse
Margaret Karow, Regeneron Pharmaceuticals
Session II: Cytokine Agonists and Antagonists
12:30 Development of Novel Interferon Molecules for the Treatment of Chronic
Hepatitis C Infection
Julian Symons, Roche Palo Alto LLC
Interferon alfa-2a played a valuable role in the treatment of chronic hepatitis C but its efficacy was limited by the short in vivo half-life that contributed to low rates of viral eradication. To overcome these drawbacks, a modified form of the drug, peginterferon alfa-2a (PEGASYS ®), was developed by attaching a 40-KD branched-chain polyethylene glycol moiety to the interferon alfa-2a molecule. Peginterferon alfa 2a (40KD) has a sustained absorption, slower rate of clearance and a longer half-life resulting in sustained levels and once-weekly administration. Results of large randomized, double-blind trials have confirmed that treatment with PEGASYS and ribavirin is more effective than conventional IFN alfa and ribavirin in patients with chronic hepatitis C and in patients co-infected with HCV and HIV. Analysis of the HCV viral dynamics during treatment with IFN alfa suggests that the antiviral and Th1 immunity inducing activities of IFN alfa play a critical role in early and late viral dynamics, respectively. In order to optimize these properties we have employed the process of in vitro directed molecular evolution by DNA family shuffling to the human IFN alfa gene family. DNA family shuffling is a method for permutation of natural genetic diversity. It mimics and extends classical breeding methods by recombining more than two parental genes in a single reaction. The power of this technology is that large improvements in phenotype can be achieved by recursively screening only a small subset of all theoretically possible progeny. In a proof of concept study, DNA shuffling of a family of over 20 human IFN alfa genes was used to derive variants with increased antiviral activities on murine cells. Interestingly, the most active clones derived from this screen were more active than the native murine IFN alfa proteins. The potential use of these rapidly evolved IFN alfa proteins in the treatment of chronic hepatitis C infection will be discussed.
1:00 Clinical Efficacy of Novel Interferons
Lawrence Blatt, Vice President, InterMune
1:30 A Cytokine Tumor Targeting Agent, IL13-PE38QQR (Cintredekin
Besudotox), Administered by Intraparenchymal Convection-Enhanced Delivery (CED) for the Treatment of Recurrent Malignant Glioma (MG)Brain Tumors
David Croteau, Director, Clinical and Medical Affairs, NeoPharm
Interleukin-13 (IL-13) is a pleiotropic immune regulatory lymphokine. IL-13 receptor over-expression on malignant glioma cells provides for selective binding by cintredekin besudotox (CB), a recombinant protein consisting of IL-13 and truncated Pseudomonas exotoxin (PEA). Following binding of CB to IL-13 receptor positive glioma cells, PEA irreversibly inhibits protein synthesis leading to cell death. CED utilizes positive pressure to deliver drugs directly to brain tissue via intracerebral catheters.
The safety and efficacy of intraparenchymal CED of CB after tumor resection in patients with recurrent MG was assessed in 3 early phase clinical studies including 51 patients.
Maximum tolerated drug concentration was 0.5 µg/mL. Most frequent adverse events were neurological in nature. Concentration-dependent imaging changes were dose limiting. Median overall survival for glioblastoma multiforme patients was 45.9 weeks compared to 20-28 weeks in published literature.
CB appears to have a favorable risk-benefit profile with encouraging patient survival.
TGFb Antagonism: Novel Treatment for Acute and Chronic Tissue Injury
Steven Ledbetter, Vice-President, Renal and Fibrotic Diseases, Genzyme
TGFb’s are pleitropic cytokines that regulate diverse aspects of growth and differentiation. These activities are reexpressed in a temporal manner during tissue repair and regeneration, however, chronic injury leads to persistent overexpression causing tissue fibrosis and loss of function. Genzyme and Cambridge Antibody Technology have partnered to develop TGFb neutralizing human monoclonal antibodies for the treatment of chronic tissue fibrosis. The lead candidate, GC1008, neutralizes all three isoforms of TGFb and is currently in phase I clinical testing in patients with idiopathic pulmonary fibrosis. GC1008 was selected for development based on criteria established through characterization of a murine monoclonal antibody, 1D11, whose TGFb neutralizing activities demonstrate the utility of this approach in preclinical models of chronic tissue injury. This presentation will focus on characterization of GC1008, and will also review data from studies of preclinical efficacy with 1D11 that demonstrate reduction of tissue fibrosis with preservation of organ function.
2:30 Refreshment Break
3:00 Development of a Human C-Reactive Protein Antisense Inhibitor
Rosanne Crooke, Cardiovascular Program, Isis Pharmaceuticals
Over the past several years, numerous studies have shown that C-reactive protein (CRP) is an independent risk factor and predictor of future cardiovascular events in patients with established coronary artery disease and in apparently healthy individuals with normal LDL-C levels. Although statins reduce CRP levels in humans to some degree, no CRP-specific therapeutic interventions are currently available. Antisense oligonucleotides (ASOs) are novel therapeutic agents that selectively reduce levels of specific mRNAs involved in various diseases. Because of the preferential distribution of ASOs to the liver, a principal site of CRP production, and increasing evidence suggesting that reduction of elevated serum CRP levels might have clinical benefits, we designed and tested several human specific CRP ASOs in vitro and in vivo. Results of these studies will be discussed in detail. The identification of a specific inhibitor of human CRP would help delineate the role of CRP in the atherothrombotic process and acute coronary syndrome.
3:30 Aptamers that Discriminate between IL-23 and IL-12 are Specific Inhibitors of IL-23 Activity In Vitro
Shannon Pendergrast, Archemix Corp.
IL-23 is a heterodimer consisting of the p40 subunit of IL-12 and a unique p19 subunit. IL-23 binds to antigen-presenting cells via a distinct receptor from IL-12 and has distinct but over-lapping affects, including the stimulation of IL-17 and Interferon gamma production. Studies using knock-out mice indicate that IL-23 rather than IL-12 is the more relevant cytokine for mouse models of multiple sclerosis and rheumatoid arthritis. Furthermore, IL-12-mediated activation of STAT4 appears to be -producing Th1essential for the development of terminally differentiated INF- cells that are important for anti-microbial responses. In contrast, IL-23 is dispensable for the primary Th1 response and the normal immune response to acute microbial infections. Instead, IL-23 has been linked to the reactivation of memory T-cells in the peripheral tissues to produce a population of cells that are highly pathogenic and essential for the establishment of organ-specific inflammation. We have used a subtractive SELEX™ (Systematic Evolution of Ligands by Exponential enrichment) strategy to generate nucleic acid aptamers to IL-23. These aptamers bind IL-23 with high affinity and discriminate in binding between IL-23 and IL-12. The aptamers are potent inhibitors IL-23-dependent signaling in vitro. These aptamers are intriguing leads for the development of novel IL-23 specific anti-inflammatory agents.
Robert Gundel, Vice President, Preclinical Research, XOMA
4:30 Small Molecule Approaches to Modulate Inflammatory Cytokines targeting Signaling Pathways
Alan Lewis, President, Celgene San Diego
5:00 Networking Reception and Poster Viewing
Day Two: Tuesday, January 31, 2006
7:15 Breakfast and Registration
Session III: Chemokines and Pathogenesis
8:00 KEYNOTE PRESENTATION
Cross-talk between Chemokine and Neuropeptide Receptors using PKC and PKA Signals
Joost Oppenheim, M.D., Chief, Laboratory of Molecular Medicine, NCI, NIH
We have observed that opioids heterologously desensitize chemokine receptors based on phosphorylation by Ca++ independent protein kinase C's (PKC). Conversely, chemokines induce desensitization and phosphorylation of opioid G Protein Coupler Receptor (GiPCR) even more effectively by involving all the PKC's. This results in the inhibition of opioid induced 1) chemotaxis, 2) calcium flux, 3) enhanced cAMP production and 4) CNS dependent analgesia. Pain perception was also enhanced by "sensitization" of the vanilloid (TRPVR1) receptor by chemokines. This was dependent on coexpression of the TRPVR1 and opioid receptors with chemokine receptors on neurons in the dorsal root ganglion of rats, and was also PKC mediated. Adenosine, which is a potent immunosuppressive metabolite, interacts with the A2a GiPCR, and desensitizes chemokine receptors, inhibiting in vitro chemotaxis and in vivo inflammatory cell recruitment. Thus, cross-talk between chemokine receptors and proximal receptors for neuropeptides, metabolites or noxious stimulants can markedly influence pathophysiological responses.
9:00 G-Protein Couple Receptor (Chemokine Receptor
Thomas Schall, President & CEO, ChemoCentryx
9:30 The Role of CXC Chemokines in Pulmonary Fibrosis
Robert Strieter, UCLA
The CXC chemokines are a unique family of cytokines known for their ability to behave in a disparate manner in the regulation of angiogenesis. The mechanisms for the different activity in regulating angiogenesis by members of this chemokine family is related to the following: 1) the presence or absence of the structural/functional motif (Glutamic acid-Leucine-Arginine; ‘ELR’ motif) that immediately precedes the first cysteine amino acid residue in the primary structure of these cytokines; 2) interferon-inducible gene expression; and 3) receptors that these chemokines use to mediate their biological activity. Members that contain the ‘ELR’ motif (ELR+) are potent promoters of angiogenesis, and mediate their angiogenic activity via binding and activating CXCR2 on endothelium. In contrast, members that are inducible by interferons and lack the ELR motif (ELR-) are potent inhibitors of angiogenesis, and bind to the alternatively splice variant of CXCR3, CXCR3B on endothelium. Moreover, a CXC chemokine biological axis is involved in mediating trafficking and extravasation of circulating mesenchymal stem cells into the lung that contribute to pulmonary fibrosis. In this presentation, I will discuss the biology of these angiogenic and angiostatic CXC chemokines, and discuss their disparate angiogenic activity in the context of pulmonary fibrosis. Furthermore, I will present our findings for circulating mesenchymal cells and their role in promoting pulmonary fibrosis that is dependent on a CXC chemokine biological axis.
10:00 Refreshment Break
10:30 Chemokine Receptors in Organ-selective Melanoma Metastasis
Sam Hwang, NCI, NIH
Cancer metastasis is the end result of a complex series of biologic events that leads to the formation of clinically significant secondary tumors at distant sites. The sites of distant metastasis are not random since certain tumors show a tendency to develop metastases in specific organs. I will show that a limited number of chemokine receptors play critical roles in determining organ-selective metastasis in melanoma by regulating chemoattraction, adhesion, and survival. In particular, roles for CC chemokine receptor 7 (CCR7) in lymph node metastasis, CXC chemokine receptor 4 (CXCR4) in pulmonary metastasis, and CCR10 in skin metastasis, using a mouse model of melanoma will be described. Inhibition of the function of these receptors decreased the ability of cancer cells to disseminate to other sites and/or block their ability to survive and form tumors. Therefore, manipulation of the chemokine network may have therapeutic potential in human malignancies.
11:00 Neuronal Actions of Inflammatory Factors
Donna Gruol, Department of Neuropharmacology, The Scripps Research Institute
11:30 Immune Stimulators
Ji Ming Wang, NCI, FCRF, NIH
Bacterial peptide fMet-Leu-Phe (fMLF) is one of the first identified chemoattractants for phagocytic leukocytes by interacting with two seven transmembrane, G protein-coupled formylpeptide receptors, FPR and its variant FPRL1. Recently a number of novel and host-derived formylpeptide receptor agonist peptides have been identified. These agonists selectively activate one or more formylpeptide receptors including another FPR variant FPRL2. Activation of formylpeptide receptors by peptide agonists results in increased cell chemotaxis, phagocytosis, and release of pro-inflammatory mediators by leukocytes. Injection of peptide agonists in mice also promotes antibody responses. Therefore, formylpeptide receptor agonists may play important roles in the pathogenesis of inflammatory and immunological diseases.
Session IV: Cytokines and Pathogenesis
Nora Sarvetnick, The Scripps Research Institute
1:30 Type 2 Diabetes: A Role Pro-Inflammatory Cytokines
Vedrana Stojanovic-Susulic, Centocor, Johnson & Johnson
2:00 Cytokines in Systemic Autoimmunity
Michael Pollard, The Scripps Research Institute
Systemic lupus erythematosus (SLE) is a multigenic disorder of unknown etiology. To investigate the role of specific genes in lupus we have examined the effects of single gene deletions on expression of systemic autoimmunity in a murine model. Deficiency of certain genes, such as CD40L, CD28, or Igh6 abrogated induction of autoimmunity. Other genes, including Igh5, IL-4, ICAM-1 or TNFRI and II, had little effect on the development of disease. Intermediate effects were observed in IL-6 and β2microglobulin deficient mice. The most interesting observations were obtained with genes related to interferon-γ. Genes involved in upregulation of IFN-γ expression did not significantly influence autoimmunity whereas absence of IFN-γ or IFN-γ receptor led to greatly reduced autoantibody responses and immunopathology. Absence of IRF-1, a gene expressed in response to IFN-γ, resulted in selective retention of anti-chromatin autoantibodies demonstrating that specific defects in signaling pathways and gene expression subsequent to IFN-γ/IFN-γ receptor interaction influence specific disease parameters. Differences in the expression of IFN-γ in subcutaneous and lymphoid tissues argue that expression of this cytokine at sites of local inflammation contributes to the development of systemic autoimmunity. These studies show that single gene deletions can have a range of outcomes varying from no effect, reduction of one or more features of disease, or suppression of all features of disease, and that all three outcomes are observed in the IFN-γ pathway.
2:30 Refreshment Break
3:00 IL-6 and Cancer
William Farrar, NCI, FCRF, NIH
Among the diverse biological activities of cytokines and growth factors, the pro-inflammatory cytokine Interleukin 6 (IL-6), is the most highly cited inflammatory molecule with autocrine and paracrine activities in a wide variety of cancers. Cancers ranging from Head and Neck, breast carcinoma, renal cell carcinoma, prostate carcinoma and lymphomas have been shown to be biologically responsive to IL-6. While IL-6 has been originally described as a growth and viability factor, it is now known that IL-6 may also control drug resistance, epigenetic gene silencing, and chromosomal instability. Most research has focused on the signal transduction pathway conveyed by the IL-6 receptor system. A trifurcating signal emerges from IL-6 binding to its receptor to include some canonical pathways of JAK-STAT activation, PI3-kianse-AKT activation, and classical ERK-MAP kinase pathways. Interventions and disruptions of the biochemical activities of these pathways have been shown to affect the various biological activities of IL-6. While antibodies to the IL-6receptor complex have been useful, other small molecule inhibitors have been tested as well the activation of natural endogenous antagonistic pathways. Much focus has emerged on the JAK-STAT pathway. Janus kinases (JAK) and their cognate transcription factors STATs, are a relatively new class of signal molecules which govern many cytokine signal transduction processes. STAT3, in particular, is over-expressed in many cancer cell types and appears to be the dominant transcription factor controlling the expression of viability or anti-apoptotic gene expressions such as bcl-2, etc. Blockade of Janus Kinases (JAKs) with tyrphostins, for example, may block all down stream signaling of the IL-6 receptor. Alternatively, various interventions affecting STAT3 transcriptional activity is sufficient to induce cellular apoptosis in a number of tumor cell types.
3:30 Regulation of Cell-mediated Immunity by Interleukin-21
Chris Clegg, Research Director, ZymoGenetics
4:00 Cytokines and the Mucus Hypersecretory Phenotype
Alan Jackson, Novartis
4:30 Oral Presentations from submitted abstracts