HIRO GOTO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Medicina Preventiva, Faculdade de Medicina - Docente
LIM/38 - Laboratório de Epidemiologia e Imunobiologia, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/38 - Laboratório de Epidemiologia e Imunobiologia, Hospital das Clínicas, Faculdade de Medicina - Líder
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- CD4(+) T Cells Alter the Stromal Microenvironment and Repress Medullary Erythropoiesis in Murine Visceral Leishmaniasis(2018) PREHAM, Olivier; PINHO, Flaviane A.; PINTO, Ana Isabel; RANI, Gulab Fatima; BROWN, Najmeeyah; HITCHCOCK, Ian S.; GOTO, Hiro; KAYE, Paul M.Human visceral leishmaniasis, a parasitic disease of major public health importance in developing countries, is characterized by variable degrees of severity of anemia, but the mechanisms underlying this change in peripheral blood have not been thoroughly explored. Here, we used an experimental model of visceral leishmaniasis in C57BL/6 mice to explore the basis of anemia following infection with Leishmania donovani. 28 days post-infection, mice showed bone marrow dyserythropoiesis by myelogram, with a reduction of TER119(+) CD71(-/+) erythroblasts. Reduction of medullary erythropoiesis coincided with loss of CD169(high) bone marrow stromal macrophages and a reduction of CXCL12-expressing stromal cells. Although the spleen is a site of extramedullary erythropoiesis and erythrophagocytosis, splenectomy did not impact the extent of anemia or affect the repression of medullary hematopoiesis that was observed in infected mice. In contrast, these changes in bone marrow erythropoiesis were not evident in B6.Rag2(-/-) mice, but could be fully reconstituted by adoptive transfer of IFN gamma-producing but not IFN gamma-deficient CD4(+) T cells, mimicking the expansion of IFN gamma-producing CD4(+) T cells that occurs during infection in wild type mice. Collectively, these data indicate that anemia during experimental murine visceral leishmaniasis can be driven by defects associated with the bone marrow erythropoietic niche, and that this represents a further example of CD4(+) T cell-mediated immunopathology affecting hematopoietic competence.
- A Global Comparative Evaluation of Commercial Immunochromatographic Rapid Diagnostic Tests for Visceral Leishmaniasis(2012) CUNNINGHAM, Jane; HASKER, Epco; DAS, Pradeep; SAFI, Sayda El; GOTO, Hiro; MONDAL, Dinesh; MBUCHI, Margaret; MUKHTAR, Maowia; RABELLO, Ana; RIJAL, Suman; SUNDAR, Shyam; WASUNNA, Monique; ADAMS, Emily; MENTEN, Joris; PEELING, Rosanna; BOELAERT, MarleenBackground. Poor access to diagnosis stymies control of visceral leishmaniasis (VL). Antibody-detecting rapid diagnostic tests (RDTs) can be performed in peripheral health settings. However, there are many brands available and published reports of variable accuracy. Methods. Commercial VL RDTs containing bound rK39 or rKE16 antigen were evaluated using archived human sera from confirmed VL cases (n = 750) and endemic non-VL controls (n = 754) in the Indian subcontinent (ISC), Brazil, and East Africa to assess sensitivity and specificity with 95% confidence intervals. A subset of RDTs were also evaluated after 60 days' heat incubation (37 degrees C, 45 degrees C). Interlot and interobserver variability was assessed. Results. All test brands performed well against ISC panels (sensitivity range, 92.8%-100%; specificity range, 96%-100%); however, sensitivity was lower against Brazil and East African panels (61.5%-91% and 36.8%-87.2%, respectively). Specificity was consistently > 95% in Brazil and ranged between 90.8% and 98% in East Africa. Performance of some products was adversely affected by high temperatures. Agreement between lots and readers was good to excellent (kappa > 0.73-0.99). Conclusions. Diagnostic accuracy of VL RDTs varies between the major endemic regions. Many tests performed well and showed good heat stability in the ISC; however, reduced sensitivity against Brazilian and East African panels suggests that in these regions, used alone, several RDTs are inadequate for excluding a VL diagnosis. More research is needed to assess ease of use and to compare performance using whole blood instead of serum and in patients coinfected with human immunodeficiency virus.
- Protein Disulfide Isomerase and Host-Pathogen Interaction(2011) STOLF, Beatriz S.; IOANNIS, Smyrnias; LOPES, Lucia R.; VENDRAMIN, Alcione; GOTO, Hiro; LAURINDO, Francisco R. M.; SHAH, Ajay M.; SANTOS, Celio X. C.Reactive oxygen species (ROS) production by immunological cells is known to cause damage to pathogens. Increasing evidence accumulated in the last decade has shown, however, that ROS (and redox signals) functionally regulate different cellular pathways in the host-pathogen interaction. These especially affect (i) pathogen entry through protein redox switches and redox modification (i. e., intra-and interdisulfide and cysteine oxidation) and (ii) phagocytic ROS production via Nox family NADPH oxidase enzyme and the control of phagolysosome function with key implications for antigen processing. The protein disulfide isomerase (PDI) family of redox chaperones is closely involved in both processes and is also implicated in protein unfolding and trafficking across the endoplasmic reticulum (ER) and towards the cytosol, a thiol-based redox locus for antigen processing. Here, we summarise examples of the cellular association of host PDI with different pathogens and explore the possible roles of pathogen PDIs in infection. A better understanding of these complex regulatory steps will provide insightful information on the redox role and coevolutional biological process, and assist the development of more specific therapeutic strategies in pathogen-mediated infections.
- miR-548d-3p Is Up-regulated in Human Visceral Leishmaniasis and Suppresses Parasite Growth in Macrophages (vol 12, 826039, 2022)(2022) RAMOS-SANCHEZ, Eduardo Milton; REIS, Luiza Campos; SOUZA, Marina de Assis; MUXEL, Sandra Marcia; SANTOS, Kamila Reis; LAGOS, Dimitris; PEREIRA, Valeria Rego Alves; BRITO, Maria Edileuza Felinto de; KAYE, Paul Martin; FLOETER-WINTER, Lucile Maria; GOTO, Hiro
- Early reduction in PD-L1 expression predicts faster treatment response in human cutaneous leishmaniasis(2021) DEY, Nidhi S.; SENARATNE, Sujai; SOMARATNE, Vijani; MADARASINGHE, Nayani P.; SENEVIRATNE, Bimalka; FORRESTER, Sarah; OCA, Marcela Montes de; REIS, Luiza Campos; MOULIK, Srija; WALRAD, Pegine B.; CHATTERJEE, Mitali; GOTO, Hiro; WICKREMASINGHE, Renu; LAGOS, Dimitris; KAYE, Paul M.; RANASINGHE, ShalindraCutaneous leishmaniasis (CL) is caused by Leishmania donovani in Sri Lanka. Pentavalent antimonials (e.g., sodium stibogluconate [SSG]) remain first-line drugs for CL with no new effective treatments emerging. We studied whole blood and lesion transcriptomes from Sri Lankan patients with CL at presentation and during SSG treatment. From lesions but not whole blood, we identified differential expression of immune-related genes, including immune checkpoint molecules, after onset of treatment. Using spatial profiling and RNA-FISH, we confirmed reduced expression of programmed death-ligand 1 (PD-L1) and indoleamine 2,3-dioxygenase 1 (IDO1) proteins on treatment in lesions of a second validation cohort and further demonstrated significantly higher expression of these checkpoint molecules on parasite-infected compared with noninfected lesional CD68+ monocytes and macrophages. Crucially, early reduction in PD-L1 but not IDO1 expression was predictive of rate of clinical cure (HR = 4.88) and occurred in parallel with reduction in parasite load. Our data support a model whereby the initial anti-leishmanial activity of antimonial drugs alleviates checkpoint inhibition on T cells, facilitating immune-drug synergism and clinical cure. Our findings demonstrate that PD-L1 expression can be used as a predictor of rapidity of clinical response to SSG treatment in Sri Lanka and support further evaluation of PD-L1 as a host-directed therapeutic in leishmaniasis.
- miR-548d-3p Is Up-Regulated in Human Visceral Leishmaniasis and Suppresses Parasite Growth in Macrophages(2022) RAMOS-SANCHEZ, Eduardo Milton; REIS, Luiza Campos; SOUZA, Marina de Assis; MUXEL, Sandra Marcia; SANTOS, Kamila Reis; LAGOS, Dimitris; PEREIRA, Valeria Rego Alves; BRITO, Maria Edileuza Felinto de; KAYE, Paul Martin; FLOETER-WINTER, Lucile Maria; GOTO, HiroVisceral leishmaniasis caused by Leishmania (Leishmania) infantum in Latin America progress with hepatosplenomegaly, pancytopenia, hypergammaglobulinemia, and weight loss and maybe lethal mainly in untreated cases. miRNAs are important regulators of immune and inflammatory gene expression, but their mechanisms of action and their relationship to pathogenesis in leishmaniasis are not well understood. In the present study, we sought to quantify changes in miRNAs associated with immune and inflammatory pathways using the L. (L.) infantum promastigote infected- human monocytic THP-1 cell model and plasma from patients with visceral leishmaniasis. We identified differentially expressed miRNAs in infected THP-1 cells compared with non-infected cells using qPCR arrays. These miRNAs were submitted to in silico analysis, revealing targets within functional pathways associated with TGF-beta, chemokines, glucose metabolism, inflammation, apoptosis, and cell signaling. In parallel, we identified differentially expressed miRNAs in active visceral leishmaniasis patient plasma compared with endemic healthy controls. In silico analysis of these data indicated different predicted targets within the TGF-beta, TLR4, IGF-I, chemokine, and HIF1 alpha pathways. Only a small number of miRNAs were commonly identified in these two datasets, notably with miR-548d-3p being up-regulated in both conditions. To evaluate the potential biological role of miR-548d-3p, we transiently transfected a miR-548d-3p inhibitor into L. (L.) infantum infected-THP-1 cells, finding that inhibition of miR-548d-3p enhanced parasite growth, likely mediated through reduced levels of MCP-1/CCL2 and nitric oxide production. Further work will be required to determine how miR-548d-3p plays a role in vivo and whether it serves as a potential biomarker of progressive leishmaniasis.
- miR-548d-3p Alters Parasite Growth and Inflammation in Leishmania (Viannia) braziliensis Infection(2021) SOUZA, Marina de Assis; RAMOS-SANCHEZ, Eduardo Milton; MUXEL, Sandra Marcia; LAGOS, Dimitris; REIS, Luiza Campos; PEREIRA, Valeria Rego Alves; BRITO, Maria Edileuza Felinto; ZAMPIERI, Ricardo Andrade; KAYE, Paul Martin; FLOETER-WINTER, Lucile Maria; GOTO, HiroAmerican Tegumentary Leishmaniasis (ATL) is an endemic disease in Latin America, mainly caused in Brazil by Leishmania (Viannia) braziliensis. Clinical manifestations vary from mild, localized cutaneous leishmaniasis (CL) to aggressive mucosal disease. The host immune response strongly determines the outcome of infection and pattern of disease. However, the pathogenesis of ATL is not well understood, and host microRNAs (miRNAs) may have a role in this context. In the present study, miRNAs were quantified using qPCR arrays in human monocytic THP-1 cells infected in vitro with L. (V.) braziliensis promastigotes and in plasma from patients with ATL, focusing on inflammatory response-specific miRNAs. Patients with active or self-healed cutaneous leishmaniasis patients, with confirmed parasitological or immunological diagnosis, were compared with healthy controls. Computational target prediction of significantly-altered miRNAs from in vitro L. (V.) braziliensis-infected THP-1 cells revealed predicted targets involved in diverse pathways, including chemokine signaling, inflammatory, cellular proliferation, and tissue repair processes. In plasma, we observed distinct miRNA expression in patients with self-healed and active lesions compared with healthy controls. Some miRNAs dysregulated during THP-1 in vitro infection were also found in plasma from self-healed patients, including miR-548d-3p, which was upregulated in infected THP-1 cells and in plasma from self-healed patients. As miR-548d-3p was predicted to target the chemokine pathway and inflammation is a central to the pathogenesis of ATL, we evaluated the effect of transient transfection of a miR-548d-3p inhibitor on L. (V.) braziliensis infected-THP-1 cells. Inhibition of miR-548d-3p reduced parasite growth early after infection and increased production of MCP1/CCL2, RANTES/CCL5, and IP10/CXCL10. In plasma of self-healed patients, MCP1/CCL2, RANTES/CCL5, and IL-8/CXCL8 concentrations were significantly decreased and MIG/CXCL9 and IP-10/CXCL10 increased compared to patients with active disease. These data suggest that by modulating miRNAs, L. (V.) braziliensis may interfere with chemokine production and hence the inflammatory processes underpinning lesion resolution. Our data suggest miR-548d-3p could be further evaluated as a prognostic marker for ATL and/or as a host-directed therapeutic target.