Ivan Plavec

Regulation of IL-17A Production Is Distinct from IL-17F in a Primary Human Cell Co-culture Model of T Cell-Mediated B Cell Activation

Improper regulation of B cell responses leads to excessive production of antibodies and contributes to the development of autoimmune disease. T helper 17 (Th17) cells also drive the development of autoimmune disease, but the role of B cells in shaping Th17 cell-mediated immune responses, as well as the reciprocal regulation of B cell responses by IL-17 family cytokines, remains unclear. The aim of this study was to characterize the regulation of IL-17A and IL-17F in a model of T cell-dependent B cell activation. Stimulation of primary human B cell and peripheral blood mononuclear cell (BT) co-cultures with α-IgM and a non-mitogenic concentration of superantigens for three days promoted a Th17 cell response as evidenced by increased expression of Th17-related gene transcripts, including Il17f, Il21, Il22, and Il23r, in CD4 T cells, as well as the secretion of IL-17A and IL-17F protein. We tested the ability of 144 pharmacologic modulators representing 91 different targets or pathways to regulate IL-17A and IL-17F production in these stimulated BT co-cultures. IL-17A production was found to be preferentially sensitive to inhibition of the PI3K/mTOR pathway, while prostaglandin EP receptor agonists, including PGE2, increased IL-17A concentrations. In contrast, the production of IL-17F was inhibited by PGE2, but selectively increased by TLR2 and TLR5 agonists. These results indicate that IL-17A regulation is distinct from IL-17F in stimulated BT co-cultures and that this co-culture approach can be used to identify pathway mechanisms and novel agents that selectively inhibit production of IL-17A or IL-17F.

Abstract 1093: BioMAP® profiling in primary human cell systems as a tool for drug discovery in inflammation and cancer

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL It is now widely accepted that chronic inflammatory events are critical contributors to both the development and progression of cancer. While the complex interrelationship between immune events and their effects on the neoplastic process remain to be defined, targeting inflammation has now become a priority of drug discovery in oncology. A major factor propelling this strategy is that both cancer cells and immune cells share many common signaling pathways that can contribute to the disease promoting microenvironment of the tumor. Drugs that target these pathways now make up a significant portion of pharmaceutical pipelines but how these compounds affect cancer cells, normal tissues and immune processes remains poorly understood. In order to develop more effective therapeutic strategies it is imperative that we understand the biological impact of compounds that target key signaling intermediates on normal and immune cells as well as neoplastic cells. BioSeek has pioneered the development of in vitro human cell-based systems (BioMAP® Systems) that recapitulate the complex signals and phenotypic responses of inflamed tissues in vivo. In addition to providing broad coverage of inflammatory targets, BioMAP® Systems model modulation of many signaling pathways relevant to cancer. Characterization of pathway-associated kinase inhibitors, including JAK, PI3K, p38MAPK, ERK, JNK and NF-κB in BioMAP® Systems has revealed activities that differentially impact inflammatory, proliferative, angiogenic and tissue remodeling processes. Secondly, profiling of 1000s of off-patent compounds through BioMAP® Systems identified agents that selectively prevent the growth of smooth muscle cells and related cancers (leiomyosarcomas and rhabdomyosarcomas) with little impact on the activation of immune cells. BioMAP® Systems provide a highly useful platform to (1) distinguish anti-inflammatory and anti-proliferative effects of various kinase inhibitors and (2) identify different phenotypic outcomes of these agents that influence cancer progression and disease resolution. Together these data will help inform the selection of more effective therapeutic strategies to target different cancers. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1093. doi:10.1158/1538-7445.AM2011-1093