Event Abstract Back to Event Induction of protective immune responses against cutaneous leishmaniasis in BALB/c mice by a vaccine containing a new low pathogenic strain of Leishmania major along with imiquimod Vahid Khaze1*, Mohammadhosein Alimohammadian1, Soheila Ajdary1, Behzad Laamerad2, Farhad Riazi-Rad1, Haideh Darabi1 and Fariborz Bahrami1 1 Pasteur Institute of Iran, Immunology, Iran 2 Payame Noor University, Biology, Iran Despite decades of research in countries around the world, an effective vaccine against leishmania infections has not yet been established. Selection of Leishmania major strains with low pathogenicity might be a straight way to protect the susceptible mice against cutaneous leishmaniasis for vaccine studies. Here we used a new low pathogenic strain of L. major (MHOM/IR/03/IPI-DA39), isolated from an endemic area of cutaneous leishmaniasis located in north of Iran (Damghan) for vaccination compared to a high pathogenic reference strain of Iran (MRHO/IR/75/ER) which has been used previously in some clinical trials. Whole killed parasites of both strains were inoculated in the hind footpad along with imiquimod as a Th1 adjuvant. BALB/c mice immunized in three doses at two weeks intervals and challenged with reference strain parasites, two weeks after the last immunization. Parasite burden by limiting dilution assay and IFNγ, IL4 mRNA expression by qRT-PCR were performed four weeks post challenge. Lesion size measurements were followed for twelve weeks. The group vaccinated with DA39+imiquimod, revealed significant decrease in the parasite burden compared to the reference strain group (3.41×108±2.19×108 and 3.21×109±1.2×109 live parasites/lymph node, respectively; p=0.05). In DA39+imiquimod group, smaller lesion size in the footpad was observed from week five to week twelve (p<0.001). Mean fold increase of IFNγ mRNA also exhibited a dominant Th1 response in DA39+imiquimod compared to reference strain group (350.80±10.55 and 198.61±45.43, respectively; p=0.01). The results indicated that using a low pathogenic strain of L. major could lead the immune responses toward partial protection against cutaneous leishmaniasis. Keywords: Low pathogenic Leishmania major, Vaccine, imiquimod, Th1 adjuvant, cutaneous leishmaniasis Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Host-pathogen interactions Citation: Khaze V, Alimohammadian M, Ajdary S, Laamerad B, Riazi-Rad F, Darabi H and Bahrami F (2013). Induction of protective immune responses against cutaneous leishmaniasis in BALB/c mice by a vaccine containing a new low pathogenic strain of Leishmania major along with imiquimod. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00184 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: 09 Mar 2013; Published Online: 22 Aug 2013. * Correspondence: Mr. Vahid Khaze, Pasteur Institute of Iran, Immunology, Tehran, Iran, vahidkhaze@pasteur.ac.ir 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 Vahid Khaze Mohammadhosein Alimohammadian Soheila Ajdary Behzad Laamerad Farhad Riazi-Rad Haideh Darabi Fariborz Bahrami Google Vahid Khaze Mohammadhosein Alimohammadian Soheila Ajdary Behzad Laamerad Farhad Riazi-Rad Haideh Darabi Fariborz Bahrami Google Scholar Vahid Khaze Mohammadhosein Alimohammadian Soheila Ajdary Behzad Laamerad Farhad Riazi-Rad Haideh Darabi Fariborz Bahrami PubMed Vahid Khaze Mohammadhosein Alimohammadian Soheila Ajdary Behzad Laamerad Farhad Riazi-Rad Haideh Darabi Fariborz Bahrami 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.