MARCIA DALASTRA LAURENTI
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Patologia, Faculdade de Medicina - Docente
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina - Líder
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- Salivary gland homogenates from wild-caught sand flies Lutzomyia flaviscutellata and Lutzomyia (Psychodopygus) complexus showed inhibitory effects on Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis infection in BALB/c mice(2014) FRANCESQUINI, Fernanda C.; SILVEIRA, Fernando T.; PASSERO, Luiz Felipe D.; TOMOKANE, Thaise Y.; CARVALHO, Ana Kely; CORBETT, Carlos Eduardo P.; LAURENTI, Marcia D.During the natural transmission of Leishmania parasites, the infected sand fly female regurgitates promastigotes into the host's skin together with its saliva. It has been reported that vector saliva contains immunomodulatory molecules that facilitate the establishment of infection. Thus, the main objective of this study was to evaluate the specificity of Lutzomyia (Lu.) flaviscutellata and Lu.(Psychodopygus) complexus salivas on the infectivity of Leishmania (L.) (Leishmania) amazonensis and L.(Viannia) braziliensis, respectively. BALB/c mice were inoculated into the skin of hind footpad with L.(L.) amazonensis and L.(V.) braziliensis promastigotes in the absence or presence of Lu.flaviscutellata and Lu.(P.) complexus salivary gland homogenates (SGHs). The evolution of the infection was evaluated by lesion size, histopathological analysis and determination of the parasite load in the skin biopsies collected from the site of infection at 4 and 8weeks PI. The lesion size and the parasite load of both groups of mice infected in the presence of SGHs were smaller than the control groups. The histopathological features showed that the inflammatory reaction was less prominent in the groups of mice infected in the presence of both SGHs when compared to the control group. The results showed that the presence of SGHs of Lu.flaviscutellata and Lu.(P.) complexus led to induction of processes that were disadvantageous to parasite establishment during infection by L.(L.) amazonensis and L.(V.) braziliensis. An inhibitory effect on Leishmania infection could be observed in both groups inoculated with SGHs, especially when the SGH from Lu.(P.) complexus was used.
- Expression of Foxp3, TGF-beta and IL-10 in American cutaneous leishmaniasis lesions(2014) RODRIGUES, F. M. D.; COELHO NETO, G. T.; MENEZES, J. G. P. B.; GAMA, M. E. A.; GONCALVES, E. G.; SILVA, A. R.; LAURENTI, M. D.; CORBETT, C. E. P.; SILVEIRA, F. T.; GOMES, C. M. C.Regulatory T cells (Tregs) are a unique population of CD25+CD4+ T cells that regulate innate and adaptive immune responses and have the ability to control the excessive or misdirected effects of the immune system. This modulation involves different mechanisms, such as the suppression of T cell proliferation and cytokine production, the secretion of suppressive cytokines (IL-10 and TGF-beta) and the induction of effector T cell apoptosis in humans with infectious diseases such as Leishmania infections. The aim of this study was to evaluate the expression of Foxp3, IL-10 and TGF-beta through immunohistochemistry in 22 skin biopsies of patients with localized cutaneous leishmaniasis (LCL) caused by Leishmania (Viannia) spp. from an endemic area in pre-Amazonian area of Maranho State, Brazil. The density of these markers was also analyzed according to the species of parasite and the progression of the disease. The cellular density was 234 cells/mmA(2) for Foxp3+ cells, 357 cells/mmA(2) for TGF-beta+ cells and 648 cells/mmA(2) for IL-10+ cells in the studied skin lesions. The analysis of the cellular density of these immunological markers in relation to the species of Leishmania demonstrated that lesions caused by L. (V.) braziliensis had a lower density of Foxp3+ cells than lesions caused by L. (Viannia) spp. The expression of IL-10 was also lower in lesions caused by L. (V.) braziliensis. There were no significant differences in TGF-beta expression between the two groups. The evaluation of these markers according to the progression of the disease did not reveal any significant differences. These findings suggest that Treg Foxp3+ cells, IL-10, and TGF-beta play important roles in the immunopathogenesis of LCL and that these roles differ depending on the causal Leishmania species.
- Modulation of inflammation response to murine cutaneous Leishmaniosis by homeopathic medicines: Thymulin 5cH(2014) SANTANA, Fabiana Rodrigues de; COELHO, Cideli de Paula; CARDOSO, Thayna Neves; LAURENTI, Marcia Dalastra; HURTADO, Elizabeth Cristina Perez; BONAMIN, Leoni VillanoBackground: In previous studies, we observed that thymulin 5cH could modulate BCG (Bacillus Calmette-Guerin) induced chronic inflammation by increasing peritoneal B1 stem cells differentiation into phagocytes and improving phagocytosis efficiency. Methods: We used the same protocol to study the effects of thymulin 5cH in the experimental murine Leishmaniasis, in order to elucidate some aspects of the parasite host relation under this homeopathic treatment. Male Balb/c mice were orally treated with thymulin 5cH or vehicle during 60 days, after the subcutaneous inoculation of 2 x 10(6) units of Leishmania (L.) amazonensis into the footpad. Washied inflammatory cell suspension from peritoneal cavity, spleen, local lymph node and infected subcutaneous tissue were harvested after 2 and 60 days from infection to quantify the inflammation cells by flow cytometry and histometry methods. Results: After a transitory increase of peritoneal T reg cells, treated mice presented, chronically, increase in the peritoneal and spleen B1 cells percentage (p = 0.0001) in relation to other cell types; more organized and exuberant inflammation response in the infection site, and decrease in the number of parasites per field inside the primary lesion (p = 0.05). No difference was seen in local lymph node histology. Conclusions: Thymulin 5cH is able to improve B1 cell activation and Leishmania (L) amazonensis phagocytosis efficiency in mice, similarly to that observed previously in BCG experimental infection.
- Serological cross-reactivity of Trypanosoma cruzi, Ehrlichia canis, Toxoplasma gondii, Neospora caninum and Babesia canis to Leishmania infantum chagasi tests in dogs(2014) ZANETTE, Mauricio Franco; LIMA, Valeria Marcal Felix de; LAURENTI, Marcia Dalastra; ROSSI, Claudio Nazaretian; VIDES, Juliana Peloi; VIEIRA, Rafael Felipe da Costa; BIONDO, Alexander Welker; MARCONDES, MaryIntroduction: The aim of this study was to evaluate the serological cross-reactivity between Leishmania sp. and other canine pathogens. Methods: Positive serum samples for Ehrlichia canis, Babesia canis, Toxoplasma gondii, Neospora caninum and Trypanosoma cruzi were tested using three serological methods enzyme linked immunosorbent assay (ELISA), indirect immunofluorescent antibody test (IFAT) and Kalazar Detect™, for canine visceral leishmaniasis. Results: Of the 57 dog samples tested, 24 (42.1%) tested positive using one of the three serological methods: 10/57 (17.5%) for ELISA, 11/57 (19.3%) for IFAT and 3/57 (5.3%) for Kalazar Detect™. Conclusions: Our results demonstrated that the presence of other infectious agents may lead to cross-reactivity on leishmaniasis serological tests.
- Comparative evaluation of the DPP (R) CVL rapid test for canine serodiagnosis in area of visceral leishmaniasis(2014) LAURENTI, M. D.; LEANDRO JR., M. V. de Santana; TOMOKANE, T. Y.; LUCCA, H. R. L. De; ASCHAR, M.; SOUZA, C. S. F.; SILVA, R. M.; MARCONDES, M.; MATTA, V. L. R. daWe investigated the performance of the DPP (R) canine visceral leishmaniasis (CVL) rapid test, a novel immunochromatographic assay launched by BioManguinhos (Brazil), which was recently included in the new Brazilian protocol for screening CVL in serological surveys. The present study compared the DPP (R) with the ELISA and IFA produced by BioManguinhos (Brazil) both with L. major-like antigens and with in-house tests using Leishmania infantum chagasi (in-house ELISA and in-house IFA). We analyzed the sera from clinically symptomatic (n = 47) and asymptomatic (n = 38) infected dogs from an endemic area of CVL, as well as from healthy (n = 18) dogs, in addition to the sera of dogs (n = 81) infected with other pathogens. The DPP (R) and the in-house ELISA showed a sensitivity of 90.6% and 94.1%, respectively, and specificity of 95.1% and 97.5%, respectively, and both presented cross-reactivity only with the sera of dogs with babesiosis, 44% for the DPP (R) and 22% for the in-house ELISA. The clinical groups were detected equally by the two assays. The ELISA BioManguinhos, IFA BioManguinhos, and in house-IFA showed a good sensitivity, 90.6%, 96.5% and 89.4%, respectively, but very low specificity, 77.8%, 69.1% and 65.8%, respectively, due to the high cross-reactivity with the sera from the animals harboring other pathogens. The in-house ELISA provided the highest accuracy (95.8%), followed by the DPP (R) (92.7%), ELISA BioManguinhos (84.3%), IFA BioManguinhos (83.1%), and in-house IFA (78.0%). The simultaneous use of the DPP (R) and ELISA BioManguinhos reached a sensitivity of 99.1% and 82.1% when used sequentially. In conclusion, the DPP (R) performed well as serological test for CVL, and detected both asymptomatic and symptomatic dogs in equal proportions. Although its sensitivity is not ideal yet, discarding the IFA and including the DPP (R) improved the accuracy of the new Brazilian CVL diagnostic protocol, particularly of detecting truly infected dogs. Moreover, considering the higher specificity of DPP (R) (95.1% vs 77.8%), positive predictive value (95.1% vs 81.1%) and positive likelihood value (18.3% vs 4.1%) in comparison with the ELISA BioManguinhos, the use of DPP (R) as a confirmatory test instead of a screening test is suggested.
- Serological and infection statuses of dogs from a visceral leishmaniasis-endemic area(2014) LARANJEIRA, Daniela Farias; MATTA, Vania Lucia Ribeiro da; TOMOKANE, Thaise Yumie; MARCONDES, Mary; CORBET, Carlos Eduardo Pereira; LAURENTI, Marcia DalastraOBJECTIVE: This study investigated the serological status of dogs living in a visceral leishmaniasis-endemic area and its correlation with the parasitological condition of the animals. METHODS: Canine humoral response was evaluated using the sera of 134 dogs by enzyme-linked immunosorbent assay and immunohistochemistry to detect parasites in the skin, lymph node, and spleen of the animals. The specific antibodies investigated were IgG, IgG1, IgG2, and IgE. RESULTS: According to the parasitological, laboratory, and clinical findings, the dogs were placed into one of four groups: asymptomatic with (AP+, n = 21) or without (AP-, n = 36) Leishmania tissue parasitism and symptomatic with (SP+, n = 52) or without (SP-, n = 25) parasitism. Higher IgG and IgE levels were positively correlated with the infection condition and parasite load, but not with the clinical status. In all groups, total IgG was the predominant antibody, which occurred at the expense of IgG2 instead of IgG1. Most of the infected dogs tested positive for IgG (SP+, 98.1%; AP+, 95.2%), whereas this was not observed with IgE (SP+, 80.8%; AP+, 71.2%). The most relevant finding was the high positivity of the uninfected dogs for Leishmania-specific IgG (SP-, 60.0%; AP-, 44.4%), IgE (SP-, 44.0%; AP-, 27.8%), IgG1 (SP-, 28.0%; AP-, 22.2%), and IgG2 antibodies (SP-, 56.0%; AP-, 41.7%). CONCLUSIONS: The serological status of dogs, as determined by any class or subclass of antibodies, did not accurately distinguish dogs infected with L. (L.) infantum chagasi from uninfected animals. The inaccuracy of the serological result may impair not only the diagnosis, but also epidemiological investigations and strategies for visceral leishmaniasis control. This complex serological scenario occurring in a visceral leishmaniasis-endemic area highlights the challenges associated with canine diagnosis and points out the difficulties experienced by veterinary clinicians and coordinators of control programs.
- Modulation of inflammation response to murine cutaneous Leishmaniasis by homeopathic medicines: Antimonium crudum 30cH(2014) SANTANA, Fabiana Rodrigues de; COELHO, Cideli de Paula; CARDOSO, Thayna Neves; HURTADO, Elizabeth Cristina Perez; BENITES, Nilson Roberti; LAURENTI, Marcia Dalastra; BONAMIN, Leoni VillanoBackground: Leishmaniasis is a zoonotic disease caused by protozoan parasites of the mononuclear phagocytic system. The modulation activity of these cells can interfere in the host/parasite relationship and influences the prognosis. Methods: We evaluated the effects of the homeopathic preparation Antimonium crudum 30cH on experimental infection induced by Leishmania (L.) amazonensis. Male Balb/c mice were inoculated with 2 x 10(6) Leishmania (L.) amazonensis promastigotes into the footpad and, after 48 h (acute phase) or 60 days (chronic phase), cell population of lymphocytes and phagocytes present in the peritoneal washing fluid and spleen were analyzed by flow cytometry and histopathology, with histometry of the subcutaneous primary lesion, local lymph node and spleen. Immunohistochemistry was performed to quantify CD3 (T lymphocyte), CD45RA (B lymphocyte) and CD11b (phagocytes) positive cells. Results: In treated mice, during the acute phase, there was significant increase of the macroscopic lesion, associated to inflammatory edema, as well increase in the number of free amastigotes and B lymphocytes inside the lesion. Increase of B lymphocytes (predominantly B-2 cells) was also seen in the local lymph node, spleen and peritoneum. In the chronic phase, the inflammatory process in the infection focus was reduced, with reduced phagocyte migration and peritoneal increase of B-1a cells (precursors of B-2 immunoglobulin producers cells) and T CD8+ cells. Conclusion: The treatment of mice with Antimonium crudum 30cH induced a predominantly B cell pattern of immune response in Leishmania (L.) amazonensis experimental infection, alongside the increase of free amastigote forms number in the infection site. The clinical significance of this study is discussed, further studies are suggested.
- Preclinical diagnosis of American visceral leishmaniasis during early onset of human Leishmania (L.) infantum chagasi-infection(2014) LIMA, Luciana Vieira do Rego; RAMOS, Patricia Karla Santos; CAMPOS, Marliane Batista; SANTOS, Thiago Vasconcelos dos; GOMES, Claudia Maria de Castro; LAURENTI, Marcia Dalastra; CORBETT, Carlos Eduardo Pereira; SILVEIRA, Fernando TobiasAmerican visceral leishmaniasis (AVL) is an infectious disease, often with long-duration evolution, caused by Leishmania (L.) infantum chagasi. However, although the disease is considered the major clinical manifestation of the link between L. (L.) i. chagasi and the human immune response, we have recently identified five clinical-immunological profiles of infection in the Brazilian Amazon: three asymptomatic (Asymptomatic Infection - AI, Sub-clinical Resistant Infection - SRI, and Indeterminate Initial Infection III), and two symptomatic ones [Symptomatic Infection - SI (=AVL) and Sub-clinical Oligosymptomatic Infection - SOI]. We confirm here the preclinical diagnosis of AVL through the IgM-antibody response in a case of an early infection (profile III) that evolved to the full disease after 6 weeks.`
- Treatment with triterpenic fraction purified from Baccharis uncinella leaves inhibits Leishmania (Leishmania) amazonensis spreading and improves Th1 immune response in infected mice(2014) YAMAMOTO, Eduardo Seiji; CAMPOS, Bruno Luiz S.; LAURENTI, Marcia Dalastra; LAGO, Joao H. G.; GRECCO, Simone dos Santos; CORBETT, Carlos E. P.; PASSERO, Luiz Felipe D.The current medications used to treat leishmaniasis have many side effects for patients; in addition, some cases of the disease are refractory to treatment. Therefore, the search for new leishmanicidal compounds is indispensable. Recently, it was demonstrated that oleanolic- and ursolic-containing fraction from Baccharis uncinella leaves eliminated the promastigote and amastigote forms of Leishmania (Leishmania) amazonensis and L. (Viannia) braziliensis without causing toxic effects for J774 macrophages. Thus, the aim of the present work was to characterize the therapeutic effect of the triterpenic fraction in L. (L.) amazonensis-infected BALB/c mice. Oleanolic- and ursolic acid-containing fraction was extracted from B. uncinella leaves using organic solvents and chromatographic procedures. L. (L.) amazonensis-infected BALB/c mice were treated intraperitoneally with triterpenic fraction during five consecutive days with 1.0 and 5.0 mg/kg of triterpenic fraction, or with 10.0 mg/kg of amphotericin B drug. Groups of mice treated with the triterpenic fraction, presented with decreased lesion size and low parasitism of the skin-both of which were associated with high amounts of interleukin-12 and interferon gamma. The curative effect of this fraction was similar to amphotericin B-treated mice; however, the final dose, required to eliminate amastigotes, was lesser than amphotericin B. Moreover, triterpenic fraction did not cause microscopic alterations in liver, spleen, heart, lung, and kidney of experimental groups. This work suggests that this fraction possesses compounds that are characterized by leishmanicidal and immunomodulatory activities. From this perspective, the triterpenic fraction can be explored as a new therapeutic agent for use against American Tegumentar Leishmaniasis.
- Antileishmanial activity evaluation of adunchalcone, a new prenylated dihydrochalcone from Piper aduncum L.(2014) PICOLO, Camilla R. Dal; BEZERRA, Mariana P.; GOMES, Kaio S.; PASSERO, Luiz Felipe D.; LAURENTI, Marcia D.; MARTINS, Euder Glendes A.; SARTORELLI, Patricia; LAGO, Joao Henrique G.Bioactivity-guided fractionation of EtOH extract from the leaves of Piper aduncum L. (Piperaceae) afforded a new dihydrochalcone, named adunchalcone. Its structure was elucidated on the basis of their spectroscopic data, primarily NMR and MS. Adunchalcone was evaluated against promastigote forms of Leishmania (L.) amazonensis, L. (V.) braziliensis, L. (V.) shawl, and L. (L.) chagasi and displayed 50% effective concentrations (EC50) of 11.03, 26.70, and 11.26 mu M, as well as selective indexes of 4.86, 2.01, 4.76 and 0.50, respectively. This compound was also tested against intracellular forms of L. (L.) amazonensis, displaying weak activity, in comparison to reference drug amphotericin B. However, despite reduced effect of adunchalcone against amastigotes of L. (L.) amazonensis, this work opens the perspective to use this particular molecule as a scaffold for the design of novel and selective drug candidates for neglected diseases, mainly leishmaniasis.