Analysis of the protective potential of the third generation vaccine pVAX1-FSD against experimental cutaneous leishmaniasis

• Grant number: 13/13348-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2013
• End date: September 30, 2014
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal Investigator: Luiz Felipe Domingues Passero
• Grantee: Thays Nicolli Fragoso da Silva
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The antigens released by parasites are interesting targets for the development of vaccine candidates, since they are one of first molecules to interact with the innate immune system, establishing an intrinsic physiological relationship with host cells. For this reason, these antigens have been target to vaccine development against murine and canine tegumentar and visceral leishmaniosis, respectively. Indeed with the recent publication of Leishmania donovani secretome has become possible develop well-defined vaccine candidates against this tropical disease; however a limiting factor for this purpose is the yield of antigen to further purification. Thus, DNA vaccines become good alternatives to circumvent the problem of protein purification, once target proteins are expressed in vivo. In the present purpose, the protective effect of DNA vaccine encoding iron superoxide dismutase of Leishmania (Leishmania) amazonensis will be evaluated, using the vector pVAX1, which was licensed to human use. BALB/c mice will be immunized with DNA vaccine, three times at regular intervals of 21 days, intramuscularly. Following 21 days of last immunization, the animals will be subcutaneously challenged in the hind footpad with L. (L.) amazonensis promastigote forms. The lesion size will be evaluated during 60 days, with weakly measurements using a micrometer. The animals will be sacrificed and skin parasitism will be evaluated by limiting-dilution assay to analyze the efficacy of vaccines. This project aims to contribute for the development of vaccine candidates against American Tegumentar Leishmaniasis.