Leishmania LiHyC protein is immunogenic and induces protection against visceral leishmaniasis

Treatment against visceral leishmaniasis (VL) presents problems by the toxicity of drugs, high cost and/or emergence of resistant strains. The diagnosis is hampered by variable sensitivity and/or specificity of tests. In this context, prophylactic vaccination could represent a control measure against disease. In this study, the protective efficacy of Leishmania LiHyC protein was evaluated in a murine model against Leishmania infantum infection. LiHyC was used as recombinant protein (rLiHyC) associated with saponin (rLiHyC/S) or Poloxamer 407-based polymeric micelles (rLiHyC/M) to immunize mice. Animals received also saline, saponin or empty micelles as controls. The immunogenicity was evaluated before and after the challenge, and results showed that vaccination with rLiHyC/S or rLiHyC/M induced the production of high levels of interferon-gamma (IFN-γ), interleukin (IL)-12 and granulocyte-macrophage colony-stimulating factor in cell culture supernatants, as well as higher IFN-γ expression evaluated by RT-qPCR and involvement from CD4+ and CD8+ T-cell subtypes producing IFN-γ, tumor necrosis factor-α and IL-2. A positive lymphoproliferative response was also found in cell cultures from vaccinated animals, besides high levels of rLiHyC- and parasite-specific nitrite and IgG2a antibodies. Immunological assays correlated with significant reductions in the parasite load in the spleens, livers, bone marrows and draining lymph nodes from vaccinated mice, when compared to values found in the controls. The micellar composition showed slightly better immunological and parasitological data, as compared to rLiHyC/S. Results suggest that rLiHyC associated with adjuvants could be considered for future studies as a vaccine candidate against VL.</p

Recombinant guanosine-5′-triphosphate (GTP)-binding protein associated with Poloxamer 407-based polymeric micelles protects against Leishmania infantum infection

Leishmania virulence proteins should be considered as vaccine candidates against disease, since they are involved in developing infection in mammalian hosts. In a previous study, a Leishmania guanosine-5′-triphosphate (GTP)-binding protein was identified as a potential parasite virulence factor. In the present work, the gene encoding GTP was cloned and the recombinant protein (rGTP) was evaluated as a vaccine candidate against Leishmania infantum infection. The protein was associated with saponin (rGTP/Sap) or Poloxamer 407-based micelles (rGTP/Mic) as adjuvants, and protective efficacy was investigated in BALB/c mice after parasite challenge. Both rGTP/Sap and rGTP/Mic compositions induced a Th1-type immune response in vaccinated animals, with significantly higher levels of IFN-γ, IL-12, IL-2, TNF-α, GM-CSF, nitrite, specific IgG2a isotype antibody and positive lymphoproliferation, when compared to the control groups. This response was accompanied by significantly lower parasite load in the spleens, livers, bone marrows and draining lymph nodes of the animals. Immunological and parasitological evaluations indicated that rGTP/Mic induced a more polarized Th1-type response and higher reduction in the organ parasitism, and with lower hepatotoxicity, when compared to the use of rGTP/Sap. In conclusion, our preliminary data suggest that rGTP could be considered for further development as a vaccine candidate to protect against VL.</p

Recombinant endonuclease III protein from <i>Leishmania infantum</i> associated with Th1-type adjuvants is immunogenic and induces protection against visceral leishmaniasis

Vaccination against visceral leishmaniasis (VL) should be considered as a safe and effective measure to disease control; however, few vaccines are available against canine VL and there is no an approved human vaccine. In this context, in the present study, we evaluated the endonuclease III (ENDO) protein, which was recently showed to be antigenic for human disease, as a vaccine candidate against Leishmania infantum infection. The recombinant protein (rENDO) was administered in BALB/c mice alone or associated with saponin (rENDO/Sap) or micelles (rENDO/Mic) as adjuvants. Controls received saline, saponin or empty micelles. Results showed that both rENDO/Sap and rENDO/Mic compositions induced higher levels of IFN-γ, IL-12, TNF-α, and GM-CSF cytokines, besides nitrite and IgG2a isotype antibodies, before and after challenge infection, which were related to both CD4+ and CD8+ T cell subtypes. The immunological results contributed to significant reductions in the parasite load found in the spleens, livers, bone marrows and draining lymph nodes of the vaccinated animals. In general, mice immunized with rENDO/Mic presented a slightly higher Th1-type cellular and humoral immune response, as compared to those receiving rENDO/Sap. In addition, saponin caused a slight to moderate inflammatory edema in their vaccinated footpads, which was not observed when micelles were used with rENDO. In addition, a preliminary analysis showed that the recombinant protein was immunogenic to human cells cultures, since PBMCs from treated VL patients and healthy subjects showed higher lymphoproliferation and IFN-γ production in the culture supernatants. In conclusion, data suggest that rENDO could be considered as a candidate to be evaluated in future studies as vaccine to protect against VL

Trajetória docente em educação física: percursos formativos e profissionais Teacher's trajectory in physical education: formative and professional routes

O presente estudo teve como objetivo analisar a trajetória docente em Educação Física. Os percursos formativos e profissionais de quatro professores de Educação Física, com mais de 25 anos de intervenção profissional em escolas estaduais da cidade de Florianópolis foram investigados. Para analisar a trajetória docente foram utilizadas três fontes de coletas de informações: a) entrevistas semi-estruturadas com os professores de Educação Física; b) entrevistas semi-estruturadas com três colegas de trabalho; c) análise documental. A técnica da análise de conteúdo foi utilizada na análise das informações. Os resultados revelaram que os professores, ao mesmo tempo em que tiveram experiências positivas diversificadas durante suas formações iniciais, vivenciaram experiências negativas muito similares, destacando-se a distância entre suas experiências formativas e a realidade das escolas públicas. Como estratégia de continuidade do percurso formativo, os docentes realizaram cursos de pós-graduação em nível de especialização e de capacitação profissional. A entrada na carreira possibilitou sentimentos tanto de sobrevivência quanto de descoberta, sobressaindo-se o choque com a realidade. No decorrer de seus percursos profissionais, assumiram cargos comissionados e de confiança nas escolas em que atuavam. O desinvestimento amargo predomina no percurso profissional de apenas um professor, enquanto os demais demonstram aguardar a aposentadoria de forma mais serena. Como expectativas relacionadas à aposentadoria, pretendem desenvolver atividades profissionais diversificadas, não retornando à docência escolar.<br>This study aimed to analyze the professional trajectory of Physical Education (PE) teachers. The formative and professional routes of four PE teachers, with more than twenty-five years of professional activity in state schools in the city of Florianopolis were investigated. To analyze the teaching trajectory it was used three sources of information: a) semi-structured interviews with the PE teachers; b) semi-structured interviews with three workmates; c) documental analysis. The technique of content analysis was used for information analysis. The results revealed that the teachers, by the same time they had different positive experiences during their initial training, they had very similar negative experiences, emphasizing the distance between University's experiences and the reality of public schools. As a strategy to continue in the formative course, teachers made post-graduation courses, for expertise and professional improvement. The start in the career made possible feelings of survive and discovery, emphasizing the contrast to the reality. During professional journey, they received activities of reliance at schools they worked. The hard disinvestment predominates in the professional journey of only one teacher, but the other demonstrated to wait for retirement in a soft way. Concerning expectations related to the retirement, they intend to develop different professional activities, but not returning to teaching activities