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Oliveira TKF, Oliveira-Silva J, Linhares-Lacerda L, da Silva Fraga-Junior V, Benjamim CF, Guimaraes-Costa AB, Saraiva EM. Leishmania infantum Axenic Amastigotes Induce Human Neutrophil Extracellular Traps and Resist NET-Mediated Killing. Trop Med Infect Dis 2023; 8:336. [PMID: 37505632 PMCID: PMC10385766 DOI: 10.3390/tropicalmed8070336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 06/16/2023] [Accepted: 06/18/2023] [Indexed: 07/29/2023] Open
Abstract
Neutrophils are multifaceted cells that, upon activation, release meshes of chromatin associated with different proteins, known as neutrophil extracellular traps (NETs). Leishmania amazonensis promastigotes and amastigotes induce NET release, and we have identified the signaling pathways involved in NET extrusion activated by promastigotes. Amastigotes maintain the infection in vertebrate hosts, and we have shown the association of NETs with amastigotes in human biopsies of cutaneous leishmaniasis. However, the interaction of amastigotes and neutrophils remains poorly understood. Our study aimed to characterize the pathways involved in the formation of NETs induced by axenic amastigotes from L. infantum, the causal agent of visceral leishmaniasis. Human neutrophils pretreated with signaling pathway inhibitors were incubated with amastigotes, and NET release was quantified in the culture supernatant. Amastigote viability was checked after incubation with NETs. We found that the release of NETs by neutrophils stimulated with these amastigotes requires the participation of elastase and peptidyl arginine deaminase and the involvement of PI3K, ROS, and calcium. Moreover, amastigotes are not susceptible to NET-mediated killing. Altogether, these findings improve our comprehension of the signaling pathways implicated in the interaction between amastigotes and human neutrophils.
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Affiliation(s)
- Thamara K F Oliveira
- Laboratório de Imunologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Jullyanna Oliveira-Silva
- Laboratório de Imunologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Leandra Linhares-Lacerda
- Laboratório de Imunologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Vanderlei da Silva Fraga-Junior
- Laboratório de Imunologia Molecular e Celular, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Claudia F Benjamim
- Laboratório de Imunologia Molecular e Celular, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Anderson B Guimaraes-Costa
- Laboratório de Imunologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Elvira M Saraiva
- Laboratório de Imunologia das Leishmanioses, Instituto de Microbiologia Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
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Março KS, da Silva Borégio J, Jussiani GG, de Souza Ferreira LFE, Flores GVA, Pacheco CMS, Laurenti MD, Machado GF. Thymic alterations resulting from experimental visceral leishmaniasis in a Syrian hamster (Mesocricetus auratus). Vet Immunol Immunopathol 2023; 257:110558. [PMID: 36758455 DOI: 10.1016/j.vetimm.2023.110558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 01/18/2023] [Accepted: 01/24/2023] [Indexed: 02/05/2023]
Abstract
BACKGROUND The thymus is a lymphoid organ responsible for the development and maturation of T cells, which are part of the Th1, Th2, Th17, and Treg immune responses triggered by visceral leishmaniasis. The maturation and immunological development of T lymphocytes require a bidirectional interaction between the thymic microenvironment of epithelial cells, dendritic cells, and macrophages and the extracellular matrix with differentiating lymphocytes. OBJECTIVES We evaluated the morphological characteristics and tissue distribution of hematopoietic and stromal cells in the thymuses of hamsters experimentally infected with Leishmania infantum, aiming to gain an insight into the pathophysiology of the disease. METHODS Fifteen hamsters were subjected to intraperitoneal experimental infection with 107L. infantum promastigotes (MHOM/BR/1972/BH46). The animals were divided into three groups, each comprising five infected hamsters, and were then euthanized 15, 60, and 120 days postinfection. The control groups consisted of three groups of five healthy hamsters euthanized simultaneously with the infected ones. Thymic morphology was evaluated through histopathology and the cell composition through immunohistochemistry. We used antibodies to mark mesenchymal cells (anti-vimentin), epithelial cells (anti-cytokeratin), macrophages (anti-MAC387), B lymphocytes (anti-CD79a), and T lymphocytes (anti-CD3). Immunohistochemistry was also used to mark the parasite in the thymus. RESULTS Infected and control hamsters showed no difference in thymic morphology and degree of atrophy. After 15 days of infection, CD3 + T lymphocytes in the thymus showed an increase that stabilized over time. At 120 days of infection, we detected a significant decrease in CD79a+ B lymphocytes. The parasite was present in the medullary and corticomedullary regions of 9 out of 15 hamsters. These findings confirm that the presence of a parasite can cause changes in a thymus cell population. However, further studies are needed to evaluate these changes' effects on the immune response of infected animals.
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Affiliation(s)
- Karen Santos Março
- Laboratory of Applied Pathology (LAPAP), Department of Animal Clinical, Surgical and Reproductive Medicine, Faculty of Veterinary Medicine, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Jaqueline da Silva Borégio
- Laboratory of Applied Pathology (LAPAP), Department of Animal Clinical, Surgical and Reproductive Medicine, Faculty of Veterinary Medicine, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Giulia Gonçalves Jussiani
- Laboratory of Applied Pathology (LAPAP), Department of Animal Clinical, Surgical and Reproductive Medicine, Faculty of Veterinary Medicine, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Laura Flávia Esperança de Souza Ferreira
- Laboratory of Applied Pathology (LAPAP), Department of Animal Clinical, Surgical and Reproductive Medicine, Faculty of Veterinary Medicine, São Paulo State University - UNESP, Araçatuba, SP, Brazil
| | - Gabriela Venicia Araujo Flores
- Laboratory of Infectious Disease Pathology (LIM/50), Department of Pathology, Faculty of Medicine, University of São Paulo - USP, São Paulo, SP, Brazil
| | - Carmen Maria Sandoval Pacheco
- Laboratory of Infectious Disease Pathology (LIM/50), Department of Pathology, Faculty of Medicine, University of São Paulo - USP, São Paulo, SP, Brazil
| | - Marcia Dalastra Laurenti
- Laboratory of Infectious Disease Pathology (LIM/50), Department of Pathology, Faculty of Medicine, University of São Paulo - USP, São Paulo, SP, Brazil
| | - Gisele Fabrino Machado
- Laboratory of Applied Pathology (LAPAP), Department of Animal Clinical, Surgical and Reproductive Medicine, Faculty of Veterinary Medicine, São Paulo State University - UNESP, Araçatuba, SP, Brazil.
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Ribeiro VM, Júnior DMG, Ottino J, Valle GR, de Miranda Estevam LGT, de Carvalho OV, Paz GF. Report of the presence of Leishmania infantum in the milk of a naturally infected female dog in Brazil. Vet Parasitol Reg Stud Reports 2022; 36:100795. [PMID: 36436888 DOI: 10.1016/j.vprsr.2022.100795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 09/22/2022] [Accepted: 10/05/2022] [Indexed: 11/07/2022]
Abstract
Dogs are the most important reservoir of Leishmania infantum, the causal agent of visceral leishmaniasis in Brazil. Although lymphoid tissue is the most important biological tissue where amastigotes can be found, this paper describes the presence of L. infantum DNA in the milk of a lactating naturally infected female dog. This finding suggests the need for further studies to elucidate whether breastfeeding can be a route of infection.
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Affiliation(s)
| | | | - Jennifer Ottino
- Santo Agostinho Hospital Veterinário, Brazil; Instituto de Ciências Biológicas da Universidade Federal de Minas Gerais, Brazil
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Savino W, Durães J, Maldonado-Galdeano C, Perdigon G, Mendes-da-Cruz DA, Cuervo P. Thymus, undernutrition, and infection: Approaching cellular and molecular interactions. Front Nutr 2022; 9:948488. [PMID: 36225882 PMCID: PMC9549110 DOI: 10.3389/fnut.2022.948488] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 09/05/2022] [Indexed: 11/29/2022] Open
Abstract
Undernutrition remains a major issue in global health. Low protein-energy consumption, results in stunting, wasting and/or underweight, three deleterious forms of malnutrition that affect roughly 200 million children under the age of five years. Undernutrition compromises the immune system with the generation of various degrees of immunodeficiency, which in turn, renders undernourished individuals more sensitive to acute infections. The severity of various infectious diseases including visceral leishmaniasis (VL), influenza, and tuberculosis is associated with undernutrition. Immunosuppression resulting from protein-energy undernutrition severely impacts primary and secondary lymphoid organs involved in the response to related pathogens. The thymus—a primary lymphoid organ responsible for the generation of T lymphocytes—is particularly compromised by both undernutrition and infectious diseases. In this respect, we will discuss herein various intrathymic cellular and molecular interactions seen in undernutrition alone or in combination with acute infections. Many examples illustrated in studies on humans and experimental animals clearly revealed that protein-related undernutrition causes thymic atrophy, with cortical thymocyte depletion. Moreover, the non-lymphoid microenvironmental compartment of the organ undergoes important changes in thymic epithelial cells, including their secretory products such as hormones and extracellular matrix proteins. Of note, deficiencies in vitamins and trace elements also induce thymic atrophy. Interestingly, among the molecular interactions involved in the control of undernutrition-induced thymic atrophy is a hormonal imbalance with a rise in glucocorticoids and a decrease in leptin serum levels. Undernutrition also yields a negative impact of acute infections upon the thymus, frequently with the intrathymic detection of pathogens or their antigens. For instance, undernourished mice infected with Leishmania infantum (that causes VL) undergo drastic thymic atrophy, with significant reduction in thymocyte numbers, and decreased levels of intrathymic chemokines and cytokines, indicating that both lymphoid and microenvironmental compartments of the organ are affected. Lastly, recent data revealed that some probiotic bacteria or probiotic fermented milks improve the thymus status in a model of malnutrition, thus raising a new field for investigation, namely the thymus-gut connection, indicating that probiotics can be envisioned as a further adjuvant therapy in the control of thymic changes in undernutrition accompanied or not by infection.
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Affiliation(s)
- Wilson Savino
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Brazilian National Institute of Science and Technology on Neuroimmunomodulation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- *Correspondence: Wilson Savino, ,
| | - Jonathan Durães
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Laboratory on Leishmaniasis Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Carolina Maldonado-Galdeano
- Laboratory of Immunology, Reference Center for Lactobacilli Centro de Referencia para Lactobacilos-Consejo Nacional de Investigaciones Científicas y Técnicas (CERELA-CONICET), San Miguel de Tucumán, Argentina
- Laboratory of Immunology, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucumán, San Miguel de Tucumán, Argentina
| | - Gabriela Perdigon
- Laboratory of Immunology, Reference Center for Lactobacilli Centro de Referencia para Lactobacilos-Consejo Nacional de Investigaciones Científicas y Técnicas (CERELA-CONICET), San Miguel de Tucumán, Argentina
- Laboratory of Immunology, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucumán, San Miguel de Tucumán, Argentina
| | - Daniella Arêas Mendes-da-Cruz
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Brazilian National Institute of Science and Technology on Neuroimmunomodulation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- School of Pharmacy and Biomedical Sciences, University of Central Lancashire, Preston, United Kingdom
| | - Patricia Cuervo
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Laboratory on Leishmaniasis Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Patricia Cuervo, ,
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Jussiani GG, Março KS, Bertolo PHL, de Oliveira Vasconcelos R, Machado GF. Thymic changes due to leishmaniasis in dogs: An immunohistochemical study. Vet Immunol Immunopathol 2022; 247:110416. [DOI: 10.1016/j.vetimm.2022.110416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/23/2022] [Accepted: 03/20/2022] [Indexed: 11/28/2022]
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High levels of anti-Leishmania IgG3 and low CD4 + T cells count were associated with relapses in visceral leishmaniasis. BMC Infect Dis 2021; 21:369. [PMID: 33874901 PMCID: PMC8056614 DOI: 10.1186/s12879-021-06051-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 03/08/2021] [Indexed: 01/10/2023] Open
Abstract
Background Visceral leishmaniasis (VL) is severe and potentially fatal. Brazil is one of the countries with the greatest endemicity for the disease in the world. The reduction of CD4+ T lymphocytes, B cells activation and high levels of inflammatory cytokines (IL-6/IL-8/TNF/IL-1β), plasma LPS, soluble CD14, anti-Leishmania IgG3 and low leptin levels are involved in the immunopathogenesis of VL, most associated with severe VL. Despite relapses occurring in about 4–5% of patients with VL not associated with HIV infection, the factors underlying relapses are little known. Our aim was to identify clinical, laboratory and immunological parameters that may be associated with recurrences in VL. Methods Fifteen VL patients recruited from Hospital Eduardo de Menezes (BH-MG) were grouped into relapsing (R-VL, n = 5) and non-relapsing (NR-VL, n = 10) and evaluated during active disease, immediately after treatment (post-treatment) and 6 months post-treatment (6mpt). Clinical and laboratory data obtained from medical records were correlated with CD4+ and CD8+ T cell counts and anti-Leishmania Igs and IL-6 plasma levels and compared to those parameters of ten healthy controls. Results During the active phase of VL, despite similarity in the clinical symptoms, the rates of thrombocytopenia, elevated transaminases (AST and ALT) and hyperbilirubinemia were higher in the NR-VL group compared to R-VL (p < 0.05), a profile reversed during the post-treatment phase. All patients had low CD4+ T counts in active phase, however, NR-VL patients had a higher gain of this cell type than R-VL in the post-treatment (p < 0.05). There was a significant reduction in IgG3 levels during the follow-up in the NR-VL group compared to the R-VL, especially at 6mpt (p < 0.05). In addition, IgG3 levels were negatively correlated with CD4+ T counts in the R-VL group (r = − 0.52). Elevated levels of IL-6 were observed in active VL and correlated with clinical markers of severity. Conclusions During active phase of VL, the NR-VL patients presented more severe laboratorial abnormalities compared to R-VL, probably because the latter had already received previous treatment. On the other hand, R-VL exhibited greater impairment of immune reconstitution and a high degree of B lymphocyte activation, which must be a factor that favored relapses. Supplementary Information The online version contains supplementary material available at 10.1186/s12879-021-06051-5.
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Domínguez-Asenjo B, Gutiérrez-Corbo C, Pérez-Pertejo Y, Iborra S, Balaña-Fouce R, Reguera RM. Bioluminescent Imaging Identifies Thymus, As Overlooked Colonized Organ, in a Chronic Model of Leishmania donovani Mouse Visceral Leishmaniasis. ACS Infect Dis 2021; 7:871-883. [PMID: 33739807 DOI: 10.1021/acsinfecdis.0c00864] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The search for new drugs against neglected parasitic diseases has experienced a major boost in recent years with the incorporation of bioimaging techniques. Visceral leishmaniasis, the second more neglected disease in the world, has effective treatments but with several disadvantages that make the search for new therapeutic solutions an urgent task. Animal models of visceral leishmaniasis that resemble the human disease have the disadvantage of using hamsters, which are an outbred breeding animal too large to obtain acceptable images with current bioimaging methodologies. Mouse models of visceral leishmaniasis seem, however, to be more suitable for early (acute) stages of the disease, but not for chronic ones. In our work, we describe a chronic Balb/c mouse model in which the infection primarily colonizes the spleen and well recreates the late stages of human disease. Thanks to the bioluminescent image, we have been able to identify experimentally, for the first time, a new primary lymphoid organ of colonization, the thymus, which appears infected from the beginning until the late phases of the infection.
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Affiliation(s)
- Bárbara Domínguez-Asenjo
- Department of Biomedical Sciences, Faculty of Veterinary Medicine, University of León, 24071 León, Spain
| | - Camino Gutiérrez-Corbo
- Department of Biomedical Sciences, Faculty of Veterinary Medicine, University of León, 24071 León, Spain
| | - Yolanda Pérez-Pertejo
- Department of Biomedical Sciences, Faculty of Veterinary Medicine, University of León, 24071 León, Spain
| | - Salvador Iborra
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), 28040 Madrid, Spain
| | - Rafael Balaña-Fouce
- Department of Biomedical Sciences, Faculty of Veterinary Medicine, University of León, 24071 León, Spain
| | - Rosa M. Reguera
- Department of Biomedical Sciences, Faculty of Veterinary Medicine, University of León, 24071 León, Spain
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Magalhães AOD, Bezerra LM, Araújo DP, Lima BSGD, Assunção LDP, Nascente EDP, Santin API, Menezes RC, Moura VMBDD. Anatomomopathological and immunohistochemical analyses of the spleen and lymph node of dogs seropositives for leishmaniasis in serological tests. CIÊNCIA ANIMAL BRASILEIRA 2021. [DOI: 10.1590/1809-6891v22e-68909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abstract Canine leishmaniasis (CanL) is a zoonosis caused by the protozoan of the species Leishmania infantum. The spleen and lymph nodes undergo morphological changes during CanL. This research aimed to perform an anatomopathological and immunohistochemical study of these organs in dogs reactive to leishmaniasis in the Dual-path Platform chromatographic immunoassay (DPP®) and Enzyme Immunoabsorption Assay (ELISA). Twenty-seven dogs were evaluated for anatomopathological examination with 92.6% showing changes at gross evaluation, specially splenomegaly and lymphadenomegaly. All dogs showed changes in the spleen unrelated to the parasitic load, with granulomatous splenitis being the most severe change. Diffuse cortical and paracortical hyperplasia, and hyperplasia and hypertrophy of the medullary cords were observed in the lymph node. Amastigote forms of Leishmania spp. were found in the spleen and lymph node at histopathological and immunohistochemical evaluations, with good agreement between these evaluations (k = 0.55, p = 0.00124), but no difference was observed in the parasitic intensity of these organs at immunohistochemistry (p = 0.23). It was concluded that spleen and lymph node from dogs reactive to leishmaniasis on the DPP® and ELISA tests show histomorphological changes resulting from the disease, independent to the parasitic load, as well as these organs show similar parasitic load at immunohistochemical test.
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da Silva AVA, de Souza TL, Figueiredo FB, Mendes AAV, Ferreira LC, Filgueira CPB, Cuervo P, Porrozzi R, Menezes RC, Morgado FN. Detection of amastigotes and histopathological alterations in the thymus of Leishmania infantum-infected dogs. IMMUNITY INFLAMMATION AND DISEASE 2020; 8:127-139. [PMID: 32207879 PMCID: PMC7212199 DOI: 10.1002/iid3.285] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/22/2019] [Accepted: 12/27/2019] [Indexed: 11/21/2022]
Abstract
Introduction In canine visceral leishmaniasis (CVL), lymphopenia, and the disorganization of lymphoid organs such as spleen and lymph nodes have been demonstrated. However, the involvement of thymus in CVL has not been evaluated so far. Herein, we investigated whether the thymus can be colonized by Leishmania infantum in naturally infected dogs. Methods Thymus were obtained from 16 of 58 dogs and samples of this organ were submitted to immunohistochemistry for laminin and fibronectin detection, histopathology, in situ hybridization and polymerase chain reaction (PCR) targeting the gene ITS‐1 for Leishmania and sequenced. Samples of spleen, skin and popliteal lymph nodes were collected and submitted to immunohistochemistry and parasitological culture followed by multilocus enzyme electrophoresis. Results L. infantum was identified in all dogs. DNA and amastigote forms of Leishmania were detected in the thymus from 16 dogs by PCR and in eight by immunohistochemistry. Besides thymus, parasites were detected in spleen, lymph nodes, and skin. A granulomatous or pyogranulomatous thymitis was observed in eight dogs associated to intact amastigotes forms of this parasite. Fibronectin deposition in thymus was higher in dogs with more clinical signs. Conclusions These results demonstrate that the thymus of dogs can be parasitized by L. infantum, which may generate inflammatory reactions leading to alterations in thymic microarchitecture.
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Affiliation(s)
- Aurea V A da Silva
- Laboratório de Pesquisa em Leishmanioses, IOC/FIOCRUZ, Rio de Janeiro, Brasil
| | - Tainã L de Souza
- Laboratório de Pesquisa em Leishmanioses, IOC/FIOCRUZ, Rio de Janeiro, Brasil
| | - Fabiano B Figueiredo
- Laboratório de Biologia Celular, Instituto Carlos Chagas, Fundação Oswaldo Cruz, Curitiba, Paraná, Brasil
| | - Artur A V Mendes
- Laboratório de Pesquisa Clínica em Dermatozoonoses em Animais Domésticos, INI/FIOCRUZ, Rio de Janeiro, Brasil
| | - Luiz C Ferreira
- Serviço de Anatomia Patológica, INI/FIOCRUZ, Rio de Janeiro, Brasil
| | | | - Patricia Cuervo
- Laboratório de Pesquisa em Leishmanioses, IOC/FIOCRUZ, Rio de Janeiro, Brasil
| | - Renato Porrozzi
- Laboratório de Pesquisa em Leishmanioses, IOC/FIOCRUZ, Rio de Janeiro, Brasil
| | - Rodrigo C Menezes
- Laboratório de Pesquisa Clínica em Dermatozoonoses em Animais Domésticos, INI/FIOCRUZ, Rio de Janeiro, Brasil
| | - Fernanda N Morgado
- Laboratório de Pesquisa em Leishmanioses, IOC/FIOCRUZ, Rio de Janeiro, Brasil
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