Imiquimod enhances anti-lymphoma response in a tumor cell lysate vaccine and inhibits tumor cells growth.

Abstract

Event Abstract Back to Event Imiquimod enhances anti-lymphoma response in a tumor cell lysate vaccine and inhibits tumor cells growth. Claudia Mongini1*, Julieta De Toro1, Leticia Hershlik1, María J. Gravisaco2, Claudia Waldner1 and Paula Di Sciullo1 1 National Research Council Of Argentina, Argentina 2 Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina Our aim was to study the immunomodulating and proapoptotic properties of the TLR7 agonist Imiquimod to be used as adjuvant in a tumor vaccine. Imiquimod showed an antiproliferative effect on LBC T-cell lymphoma in vitro at 48 and 72 h with doses between 0.5 and 200 μg/ml, inducing apoptosis in a dose dependent manner. BALB/c mice inoculated intraperitoneally twice with LBC cells lysates with or without 100 μg/mouse of Imiquimod and challenged one week later with LBC cells intraperitoneally, showed a significant increase in survival compared to un-immunized controls (LBC-lysate<0.05, LBC-lysate + IMQ<0.0005) and to mice receiving Imiquimod (p<0.0002; Logrank).Tumor incidence was only 5±5% in LBC-lysate+IMQ group whereas in LBC-lysate group was 52.5±2.5%. Although the percentages of specific cytotoxicity were above normal in both immunized groups (p<0.05, ANOVA), LBC-lysate+IMQ immunization induced the highest levels. A significant enhance in peritoneal cavity CD8+, CD4+ T and B cells (p<0.0001, ANOVA) with an increase IFNγ in supernatant from peritoneal cavity cells and splenocytes was demonstrated in all vaccinated groups compared to normal (p<0.001, ANOVA). Our vaccine also generated circulating antibodies in all immunized mice that rejected the tumor up to 75 days after challenge. Finally, mice that rejected the first tumor challenge were re-challenged with LBC tumor with an increased in survival in all immunized groups over the control (p<0.01, Logrank) with rejection rates close to 100%. We demonstrated that Imiquimod not only modulates immune response efficiently to reject tumor generating a long-lasting memory, but also is capable of inducing tumor apoptosis. Keywords: imiquimod, T-cell lymphoma, TLR7 agonist, Apoptosis, tumor cell lysate vaccine Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Translational immunology and immune intervention Citation: Mongini C, De Toro J, Hershlik L, Gravisaco MJ, Waldner C and Di Sciullo P (2013). Imiquimod enhances anti-lymphoma response in a tumor cell lysate vaccine and inhibits tumor cells growth.. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.01162 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 31 Jul 2013; Published Online: 22 Aug 2013. * Correspondence: Dr. Claudia Mongini, National Research Council Of Argentina, Buenos Aires, Buenos Aires, 1121, Argentina, cmongini@yahoo.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Claudia Mongini Julieta De Toro Leticia Hershlik María J Gravisaco Claudia Waldner Paula Di Sciullo Google Claudia Mongini Julieta De Toro Leticia Hershlik María J Gravisaco Claudia Waldner Paula Di Sciullo Google Scholar Claudia Mongini Julieta De Toro Leticia Hershlik María J Gravisaco Claudia Waldner Paula Di Sciullo PubMed Claudia Mongini Julieta De Toro Leticia Hershlik María J Gravisaco Claudia Waldner Paula Di Sciullo Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.