First generation vaccine formulated with a ligand of the Toll-like Receptor 3 protects BALB/c mice against infection with Leishmania (Leishmania) amazonensis

GERMANO MARIA JOSE; SALOMON MARÍA CRISTINA; MORENO SOSA TAMARA ; SCODELLER EDUARDO; CARGNELUTTI DIEGO ESTEBAN

Toledo, España

Congreso; 6th World Congress on Leishmaniasis; 2017

Facultad de Ciencias Exactas, Universidad Nacional de La plata

Background: Increasingly cases of cutaneous leishmaniasis in different countries have been detected. In Argentina, there are three principal species responsible that this happens, which are: L. amazonensis, L. guyanensis and L. braziliensis. Therefore it is very important develop an effective vaccine to protect other people from this disease. The objective of the present study was to evaluate the efficacy of a first-generation vaccine against leishmaniasis, formulated with the poliinosinic-policitidilic acid [Poly (I:C)] as adjuvant, which is an analog of double-stranded RNA and it acts as TLR3 ligand. Methodology: A mixture of 100 μg of Total Leishmania (Leishmania) amazonensis Antigen (TLA) plus 50 μg of Poly (I:C) was tested in mice BALB/c using a homologous prime/boost immunization. The humoral and cellular immune response generated by each formulation was evaluated. Subsequently, mice were infected with 1 x 105 of L. (L.) amazonensis promastigotes (MHOM/VE/84/MEL strain). The progress of the infection was assessed during 11 weeks, the parasite load was quantified and histopathologic at the primary site of infection studies were made. Results: The ATL-Poly (I:C) formulation generated an increase of IgG anti-ATL (P