Vaccination with a Leishmania infantum HSP70-II null mutant confers long-term protective immunity against Leishmania major infection in two mice models

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2018-04-05T18:27:03Z No. of bitstreams: 1 Solana JC Vaccination with a Leishmania infantum ....pdf: 2520651 bytes, checksum: bbd1b9c3d062625247cdc6fc413b4517 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2018-04-05T18:56:36Z (GMT) No. of bitstreams: 1 Solana JC Vaccination with a Leishmania infantum ....pdf: 2520651 bytes, checksum: bbd1b9c3d062625247cdc6fc413b4517 (MD5)Made available in DSpace on 2018-04-05T18:56:36Z (GMT). No. of bitstreams: 1 Solana JC Vaccination with a Leishmania infantum ....pdf: 2520651 bytes, checksum: bbd1b9c3d062625247cdc6fc413b4517 (MD5) Previous issue date: 2017Ministerio de Ciencia e Innovacion FISPI14/00366 (FEDER FUNDING)Universidad Autonoma de Madrid. Centro de Biologia Molecular Severo Ochoa. Departamento de Biologia Molecular. Nicolas Cabrera. Madrid, SpainUniversidad Autonoma de Madrid. Centro de Biologia Molecular Severo Ochoa. Departamento de Biologia Molecular. Nicolas Cabrera. Madrid, SpainUniversidad Autonoma de Madrid. Centro de Biologia Molecular Severo Ochoa. Departamento de Biologia Molecular. Nicolas Cabrera. Madrid, SpainFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilUniversidad Autonoma de Madrid. Centro de Biologia Molecular Severo Ochoa. Departamento de Biologia Molecular. Nicolas Cabrera. Madrid, SpainUniversidad Autonoma de Madrid. Centro de Biologia Molecular Severo Ochoa. Departamento de Biologia Molecular. Nicolas Cabrera. Madrid, SpainUniversidad Autonoma de Madrid. Centro de Biologia Molecular Severo Ochoa. Departamento de Biologia Molecular. Nicolas Cabrera. Madrid, SpainThe immunization with genetically attenuated Leishmania cell lines has been associated to the induction of memory and effector T cell responses against Leishmania able to control subsequent challenges. A Leishmania infantum null mutant for the HSP70-II genes has been described, possessing a non-virulent phenotype. Methodology/Principal findings The L. infantum attenuated parasites (LiΔHSP70-II) were inoculated in BALB/c (intravenously and subcutaneously) and C57BL/6 (subcutaneously) mice. An asymptomatic infection was generated and parasites diminished progressively to become undetectable in most of the analyzed organs. However, inoculation resulted in the long-term induction of parasite specific IFN-γ responses able to control the disease caused by a challenge of L. major infective promastigotes. BALB/c susceptible mice showed very low lesion development and a drastic decrease in parasite burdens in the lymph nodes draining the site of infection and internal organs. C57BL/6 mice did not show clinical manifestation of disease, correlated to the rapid migration of Leishmania specific IFN-γ producing T cells to the site of infection. Conclusion/Significance Inoculation of the LiΔHSP70-II attenuated line activates mammalian immune system for inducing moderate pro-inflammatory responses. These responses are able to confer longterm protection in mice against the infection of L. major virulent parasites