THAISE YUMIE TOMOKANE
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Patologia, Faculdade de Medicina
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina
LIM/50 - Laboratório de Patologia das Moléstias Infecciosas, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
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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.
- 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.
- Dynamic of the Cellular Immune Response at the Dermal Site of Leishmania (L.) amazonensis and Leishmania (V.) braziliensis Infection in Sapajus apella Primate(2014) LAURENTI, Marcia Dalastra; PASSERO, Luiz Felipe Domingues; TOMOKANE, Thaise Yumie; FRANCESQUINI, Fernanda de Camargo; ROCHA, Mussya Cisotto; GOMES, Claudia Maria de Castro; CORBETT, Carlos Eduardo Pereira; SILVEIRA, Fernando TobiasThe purpose of this study was to characterize the immunopathological response in the skin of S. apella infected with Leishmania (L.) amazonensis and L. (V.) braziliensis parasites, the main causative agents of localized cutaneous leishmaniasis in South America. In infected animals, amastigote forms of L. (L.) amazonensis could be detected till 120 days postinfection (PI), while, in L. (V.) braziliensis infection, parasites could be detected until 180 days PI in the skin sections. CD20(+) cells were detected throughout the experimental time in both groups as well as in CD3(+) cells, which appeared to be activated because high densities of inducible nitric oxide synthase (iNOS(+)) cells were detected at 60 and 90 days PI in both studied groups. After 60 and 120 days PI, decrease in iNOS(+) cells was observed in L. (L.) amazonensis and L. (V.) braziliensis, respectively, which was associated with parasite clearance. Increase in lysozyme(+) cells was observed during the experimental infections, which also can be associated with parasite killing.
- Expression of inducible nitric oxide synthase in macrophages inversely correlates with parasitism of lymphoid tissues in dogs with visceral leishmaniasis(2014) SANCHES, Francoise P.; TOMOKANE, Thaise Y.; MATTA, Vania L. R. Da; MARCONDES, Mary; CORBETT, Carlos E. P.; LAURENTI, Marcia D.Background: There are only a few studies reporting the role of nitric oxide metabolites for controlling macrophage intracellular parasitism, and these are controversial. Therefore, the present study aimed to evaluate the expression of inducible nitric oxide synthase (iNOS) in the lymph nodes and spleen of dogs affected by visceral leishmaniasis through immunohistochemistry and to determine its correlation with tissue parasite burden and serum interferon (IFN)-gamma levels. Twenty-eight dogs were selected and assigned to one of two groups, symptomatic (n = 18) and asymptomatic (n = 10), according to clinical status and laboratory evaluation. A negative control group (n = 6) from a non-endemic region for visceral leishmaniasis was included as well. Results: Parasite density (amastigotes/mm(2)) was similar between clinical groups in the lymph nodes (P = 0.2401) and spleen (P = 0.8869). The density of iNOS(+) cells was higher in infected dogs compared to controls (P < 0.05), without a significant difference in lymph node (P = 0.3257) and spleen (P = 0.5940) densities between symptomatic and asymptomatic dogs. A positive correlation was found between the number of iNOS(+) cells in lymph nodes and interferon-gamma levels (r = 0.3776; P = 0.0303), and there was a negative correlation between parasites and iNOS+ cell densities both in lymph nodes (r = -0.5341; P = 0.0034) and spleen (r = -0.4669; P = 0.0329). Conclusion: The negative correlation observed between tissue parasitism and the expression of iNOS may be a reflection of NO acting on the control of parasites.