JOSE ANGELO LAULETTA LINDOSO
Projetos de Pesquisa
Unidades Organizacionais
LIM/49 - Laboratório de Protozoologia, Hospital das Clínicas, Faculdade de Medicina - Líder
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
- Dynamics of immunosuppression in hamsters with experimental visceral leishmaniasis(2011) FAZZANI, C.; GUEDES, P. A.; SENA, A.; SOUZA, E. B.; GOTO, H.; LINDOSO, J. A. L.Immunosuppression has been reported to occur during active visceral leishmaniasis and some factors such as the cytokine profile may be involved in this process. In the mouse model of cutaneous leishmaniasis using Leishmania (Leishmania) major, the Th1 response is related to protection while the Th2 response is related to disease progression. However, in hamsters, which are considered to be an excellent model for the study of visceral leishmaniasis, this dichotomy is not observed. Using outbred 45- to 60-day-old (140 to 150 g) male hamsters infected intraperitoneally with 2 x 10(7) L. (L.) chagasi amastigotes, we evaluated the immune response of spleen cells and the production of cytokines. We used 3 to 7 hamsters per group evaluated. We detected a preserved response to concanavalin A measured by index of proliferation during all periods of infection studied, while a proliferative response to Leishmania antigen was detected only at 48 and 72 h post-infection. Messenger RNA from cytokines type 1 (IL-2, TNF-alpha, IFN-gamma) and type 2 (IL-4, IL-10 and TGF-beta) detected by reverse transcriptase polymerase chain reaction and produced by spleen cells showed no qualitative difference between control non-infected hamsters and infected hamsters during any period of infection evaluated. Cytokines were measured by the DNA band intensity on agarose gel using the Image Lab 1D L340 software with no differences observed. In conclusion, the present results showed an antigen-dependent immunosuppression in hamsters with active visceral leishmaniasis that was not related to the cytokine profile.
- Photodynamic Therapy Using Methylene Blue to Treat Cutaneous Leishmaniasis(2011) SONG, Dennis; LINDOSO, Jose Angelo Lauletta; OYAFUSO, Luiza Keiko; KANASHIRO, Edite Hatsumi Yamashiro; CARDOSO, Joao Luiz; UCHOA, Adjaci F.; TARDIVO, Joao Paulo; BAPTISTA, Mauricio S.Objective: The purpose of this study was to show the efficiency and underlying mechanism of action of photodynamic therapy (PDT) using methylene blue (MB) and non-coherent light sources to treat cutaneous leishmaniasis (CL). Background data: Systemic treatment can cause severe side effects, and PDT using porphyrin precursors as sensitizers has been used as an alternative to treat CL. MB has been used under illumination or in the dark to treat a wide range of medical conditions, and it exhibits antimicrobial activity against protozoa and viruses. Methods: In in vitro tests, the cell viability (via a MTT colorimetric assay) of Leishmania amazonensis parasites was evaluated as a function of MB concentration. In in vivo experiments, we analyzed the treatment of two lesions from a patient with leishmaniasis. The patient received a low dose of pentavalent antimony (SbV), and one lesion was treated with PDT. Results: We observed IC(50) decreases from 100 to 20 mu M in response to PDT when MB was used in different concentrations in in vitro tests. Use of SbV in combination with the PDT protocol produced faster wound recovery when compared with the use of SbV alone. Conclusions: The in vitro experiments and the results from the clinical case suggest that the inexpensive PDT protocol that is based on MB and RL50 (R) may be used to treat CL caused by L. amazonensis.