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1.
Microb Pathog ; 154: 104864, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33771629

RESUMO

Paracoccidioidomycosis (PCM) is a systemic fungal disease caused by Paracoccidioides spp., whose clinical outcome depends on immune response. Interleukin 32 (IL-32) is a cytokine present in inflammatory and infectious diseases, including bacterial, virus and protozoan infections. Its role in fungal disease remains unclear. The axis IL-15, IL-32 and vitamin D leads to microbicidal capacity against intracellular pathogens. Thus, the aims of this study were to investigate the production of IL-32 during Paracoccidioides spp. infection and whether this cytokine and IL-15 can increase P. brasiliensis control in a vitamin D dependent manner. IL-32 was highly detected in oral lesions from patients with PCM. In addition, high production of this cytokine was intracellularly detected in peripheral blood mononuclear cells (PBMCs) from healthy donors after exposure to particulated P. brasiliensis antigens (PbAg). The IL-32γ isoform was predominantly expressed, but there was mRNA alternative splicing for IL-32α isoform. The induction of IL-32 was dependent on Dectin-1 receptor. Infection of PBMCs with P. brasiliensis yeasts did not significantly induce IL-32 production even after activation with exogenous IFN-γ or IL-15 treatments. Although IL-15 was a potent inducer of IL-32 production, treatment with this cytokine did not increase the fungal control unless vitamin D was present in high levels. In this case, both IL-15 and IL-32 increased fungicidal activity of PBMCs. Together, data showed that IL-32 is present in lesions of PCM, PbAg induces IL-32, and the axis of IL-15/IL-32/vitamin D can contribute to control fungal infection. The data suggest that exposure to molecules from P. brasiliensis, as ß-glucans, is needed to induce IL-32 production since only heat-killed and sonicated P. brasiliensis yeasts were able to increase IL-32, which was blocked by anti-Dectin-1 antibodies. This is the first description about IL-15/IL-32/vitamin D pathway role in P. brasiliensis infection.

2.
Parasitol Int ; 76: 102097, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32114085

RESUMO

How human macrophages can control the intracellular infection with Leishmania is not completely understood. IL-15 and IL-32 are cytokines produced by monocytes/macrophages that can induce antimicrobial mechanisms. Here, we evaluated the effects of recombinant human IL-15 (rhIL-15) on primary human macrophage infection and response to L. braziliensis. Priming with rhIL-15 reduced the phagocytosis of L. braziliensis and increased the killing of the parasites in monocyte-derived macrophages from healthy donors. rhIL-15 induced TNFα and IL-32 in uninfected cells. After infection, the high levels of rhIL-15-induced TNFα and IL-32 were maintained. In addition, there was an increase of NO and an inhibition of the parasite-induced IL-10 production. Inhibition of NO reversed the leishmanicidal effects of rhIL-15. Although rhIL-15 did not increase L. braziliensis-induced reactive oxygen intermediates (ROS) production, inhibition of ROS reversed the control of infection induced by rhIL-15. Treatment of the cells with rhIL-32γ increased microbicidal capacity of macrophages in the presence of high levels of vitamin D (25D3), but not in low concentrations of this vitamin. rhIL-15 together with rhIL-32 lead to the highest control of the L. braziliensis infection in high concentrations of vitamin D. In this condition, NO and ROS mediated rhIL-32γ effects on microbicidal activity. The data showed that priming of human macrophages with rhIL-15 or rhIL-32γ results in the control of L. braziliensis infection through induction of NO and ROS. In addition, rhIL-32γ appears to synergize with rhIL-15 for the control of L. braziliensis infection in a vitamin D-dependent manner.


Assuntos
Antiparasitários/metabolismo , Interleucina-15/metabolismo , Interleucinas/metabolismo , Leishmania braziliensis/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Vitamina D/metabolismo , Antiparasitários/farmacologia , Interleucina-15/farmacologia , Interleucinas/farmacologia , Leishmania braziliensis/fisiologia , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Vitamina D/farmacologia
3.
PLoS Negl Trop Dis ; 14(2): e0008029, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32023240

RESUMO

Interleukin-32 is a novel inflammatory mediator that has been described to be important in the immunopathogenesis and control of infections caused by Leishmania parasites. By performing experiments with primary human cells in vitro, we demonstrate that the expression of IL-32 isoforms is dependent on the time exposed to L. amazonensis and L. braziliensis antigens. Moreover, for the first time we show the functional consequences of three different genetic variations in the IL32 (rs4786370, rs4349147, rs1555001) modulating IL-32γ expression, influencing innate and adaptive cytokine production after Leishmania exposure. Using a Brazilian cohort of 107 American Tegumentary Leishmaniasis patients and a control cohort of 245 healthy individuals, the IL32 rs4786370 genetic variant was associated with protection against ATL, whereas the IL32 rs4349147 was associated with susceptibility to the development of localized cutaneous and mucosal leishmaniasis. These novel insights may help improve therapeutic strategies and lead to benefits for patients suffering from Leishmania infections.


Assuntos
Predisposição Genética para Doença , Variação Genética , Interleucinas/genética , Leishmania/classificação , Leishmaniose Cutânea/genética , Adulto , Idoso , Brasil/epidemiologia , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/metabolismo , Masculino , Pessoa de Meia-Idade , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Isoformas de Proteínas , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
4.
Cell Rep ; 28(10): 2659-2672.e6, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484076

RESUMO

American tegumentary leishmaniasis is a vector-borne parasitic disease caused by Leishmania protozoans. Innate immune cells undergo long-term functional reprogramming in response to infection or Bacillus Calmette-Guérin (BCG) vaccination via a process called trained immunity, conferring non-specific protection from secondary infections. Here, we demonstrate that monocytes trained with the fungal cell wall component ß-glucan confer enhanced protection against infections caused by Leishmania braziliensis through the enhanced production of proinflammatory cytokines. Mechanistically, this augmented immunological response is dependent on increased expression of interleukin 32 (IL-32). Studies performed using a humanized IL-32 transgenic mouse highlight the clinical implications of these findings in vivo. This study represents a definitive characterization of the role of IL-32γ in the trained phenotype induced by ß-glucan or BCG, the results of which improve our understanding of the molecular mechanisms governing trained immunity and Leishmania infection control.


Assuntos
Imunidade , Interleucinas/metabolismo , Leishmania braziliensis/fisiologia , Leishmaniose Cutânea/prevenção & controle , beta-Glucanas/farmacologia , Adulto , Idoso , Animais , Vacina BCG/imunologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Feminino , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunidade/efeitos dos fármacos , Interleucina-1/metabolismo , Leishmania braziliensis/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Masculino , Camundongos Transgênicos , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Vacinação , Adulto Jovem
5.
Microbes Infect ; 21(8-9): 401-411, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30951888

RESUMO

Paracoccidioidomycosis (PCM), caused by thermodimorphic fungi of the Paracoccidioides genus, is a systemic disorder that involves the lungs and other organs. The adherence of pathogenic microorganisms to host tissues is an essential event in the onset of colonization and spread. The host-pathogen interaction is a complex interplay between the defense mechanisms of the host and the efforts of pathogenic microorganisms to colonize it. Therefore, the identification of fungi proteins interacting with host proteins is an important step understanding the survival strategies of the fungus within the host. In this paper, we used affinity chromatography based on surface proteomics (ACSP) to investigate the interactions of pathogen proteins with host surface molecules. Paracoccidioides lutzii extracts enriched of surface proteins were captured by chromatographic resin, which was immobilized with macrophage cell surface proteins, and identified by mass spectrometry. A total of 215 proteins of P. lutzii were identified interacting with macrophage proteins. In silico analysis classified those proteins according to the presence of sites for N- and O-glycosylation and secretion by classical and non-classical pathways. Serine proteinase (SP) and fructose-1,6-bisphosphate aldolase (FBA) were identified in our proteomics analysis. Immunolocalization assay and flow cytometry both showed an increase in the expression of these two proteins during host-pathogen interaction.


Assuntos
Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Macrófagos/metabolismo , Proteínas de Membrana/metabolismo , Paracoccidioides/fisiologia , Animais , Parede Celular/química , Parede Celular/metabolismo , Frutose-Bifosfato Aldolase/genética , Frutose-Bifosfato Aldolase/metabolismo , Proteínas Fúngicas/genética , Proteínas Imobilizadas/metabolismo , Macrófagos/microbiologia , Camundongos , Paracoccidioides/metabolismo , Ligação Proteica , Proteômica , Células RAW 264.7 , Serina Proteases/genética , Serina Proteases/metabolismo
6.
Neuroimmunomodulation ; 26(2): 77-83, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30897575

RESUMO

OBJECTIVE: Multiple sclerosis (MS) is a multifactorial chronic disease that affects the central nervous system (CNS). Toll-like receptors (TLRs) play a central role in cytokine production after pathogen- and danger-associated molecular patterns (PAMPs and DAMPs) and contribute to CNS damage in MS patients. Here, we evaluated the effects of interferon (IFN)-ß treatment in TLR2 and TLR4-dependent cytokine production and mRNA expression in whole-blood cell cultures from MS patients. METHODS: We evaluated cytokine production by ELISA from whole-blood cell culture supernatants and mRNA expression by real-time polymerase chain reaction in peripheral blood mononuclear cells (PBMCs). RESULTS: In patients treated with IFN-ß, tumor necrosis factor (TNF)-α production after exposure to TLR2 agonist (Pam3Cys) was lower than in healthy controls and untreated MS patients. However, IFN-ß treatment had no significant effect on TNF-α production after TLR4 agonist (LPS) stimulation. On the other hand, interleukin (IL)-10 production was increased in TLR4- but not in TLR2-stimulated whole-blood cell culture from MS patients under IFN-ß treatment when compared to the controls. No differences in TNF-α or IL-10 mRNA expression in PBMCs from healthy controls and untreated or treated MS patients were detected, although PBMCs from treated patients presented higher levels of IL-32γ mRNA than those from controls. CONCLUSIONS: Our data suggest that IFN-ß treatment alters the TLR-dependent immune response of PBMCs from MS patients. This may contribute to the beneficial effects of IFN-ß treatment.


Assuntos
Interferon beta/uso terapêutico , Interleucina-10/biossíntese , Esclerose Múltipla/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Adulto , Citocinas/biossíntese , Citocinas/efeitos dos fármacos , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia
7.
Parasite Immunol ; 41(5): e12623, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30870579

RESUMO

Phenotypic and functional aspects of monocytes from Localized Cutaneous Leishmaniasis (LCL) patients were evaluated. The frequencies of monocyte subsets and TLR2/TLR4 expression were evaluated in fresh peripheral blood whereas cytokine production was evaluated in whole blood cell cultures stimulated with TLR agonists or Leishmania braziliensis antigen (Ag). CD16+ monocytes frequency was increased in patients compared with controls. A TLR4 agonist (LPS) induced expression of TNF and IL-10 in monocyte subsets of patients and controls. The CD14+ CD16+ monocytes expressed higher levels of these cytokines than CD14+ CD16- cells. The levels of secreted TNF were higher in whole blood cell cultures from patients than controls after LPS/TLR4 or Ag stimulation. Whereas in controls there was a positive correlation between TNF and IL-10 levels, this was not observed in stimulated cell cultures from patients. The high levels of LPS-induced TNF were associated with the number of lesions and the percentages of CD14hi CD16+ monocytes. The levels of TLR2-induced TNF were also associated with number of lesions. All monocyte subsets from patients expressed higher levels of TLR2 and TLR4 than controls. Data suggest that systemically activated monocytes contribute for an imbalance in pro- and anti-inflammatory cytokine production during LCL, participating in the immunopathogenesis of the disease.


Assuntos
Leishmaniose Cutânea/imunologia , Adulto , Idoso , Citocinas/imunologia , Feminino , Humanos , Interleucina-10/imunologia , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Adulto Jovem
8.
Cell Immunol ; 337: 54-61, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30773217

RESUMO

Dendritic cells (DC) have the unique ability to capture microorganisms and activate naive T lymphocytes. Obtaining DC derived from progenitors demands high cost and prolonged cultivation. Different immortalized DC has been isolated but most of them have immature phenotype and depending on growing factors or other stimuli to be used. In this study we characterized the cell line AP284 as a DC. AP284 cells express high levels of CD11b, MHC class II, 33D1 and CD209b. They also express high amounts of CD80 costimulatory molecule and different toll like receptors (TLR). After stimuli with TLR agonist they produce surprising amount of IL-12p40 related to IL-23 formation but not IL-12p70. They are also able to produce IL-6 and favor amplification of a Th17 but not Th1 profile. This DC line may be useful for a better understanding of factors and cellular interactions responsible for the induction of IL-12p40, IL-23 and Th17 generation.


Assuntos
Técnicas de Cultura de Células/métodos , Células Dendríticas/imunologia , Células Th17/metabolismo , Animais , Diferenciação Celular , Linhagem Celular/metabolismo , Células Cultivadas , Células Dendríticas/metabolismo , Interleucina-12/metabolismo , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Th1/imunologia , Células Th17/imunologia , Receptor 7 Toll-Like/metabolismo , Receptores Toll-Like/metabolismo
9.
Parasitology ; : 1-12, 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30588899

RESUMO

Leishmania (Viannia) guyanensis is one species that causes cutaneous leishmaniasis in the New World. The incidence of infections with this parasite is probably underestimated and few studies exist on this species, despite its epidemiological importance. In particular, there are no studies concerning L. guyanensis metacyclogenesis and no technique for obtaining metacyclic promastigotes for this species is presently available. Here, we have studied L. guyanensis metacyclogenesis in axenic culture, describing the main changes that occur during this process, namely, in morphology and size, sensitivity to complement-mediated lysis, surface carbohydrates and infectivity to macrophages. We have shown that metacyclogenesis in L. guyanensis promastigotes is basically complete on the 4th day of culture, as determined by decreased body size, increased flagellum length, resistance to complement-mediated lysis and infectivity. We have also found that only a fraction of the parasites is agglutinated by Bauhinia purpurea lectin. The non-agglutinated parasites, which also peaked on the 4th day of culture, had all morphological traits typical of the metacyclic stage. This is the first report describing metacyclogenesis in L. guyanensis axenic promastigotes and a simple and efficient method for the purification of metacyclic forms. Furthermore, a model of human macrophage infection with L. guyanensis was established.

10.
Am J Trop Med Hyg ; 99(5): 1165-1169, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30203744

RESUMO

The disseminated form of leishmaniasis is a serious and rare disease, being diagnosed in 2% of the cutaneous cases registered per year in Brazil. The main characteristic is the appearance of multiple pleomorphic lesions on the cutaneous surface. A 68-year-old male from the rural area of Tocantins, Brazil, presented atypical disseminated cutaneous leishmaniasis (ACL). The clinical course and histopathological and immunological findings presented a mixed pattern that hindered diagnosis and therapeutic management. Molecular typing revealed a mixed infection with Leishmania (V.) guyanensis and Leishmania (L.) amazonensis. Molecular identification of the agents responsible for ACL is important for adequate therapeutic planning, minimizing the possibility of sequellae that impact the quality of life of the patient.


Assuntos
Coinfecção/diagnóstico , Coinfecção/parasitologia , Leishmania guyanensis/genética , Leishmania mexicana/genética , Leishmaniose Cutânea/diagnóstico , Idoso , Anfotericina B/uso terapêutico , Antiprotozoários/uso terapêutico , Brasil , DNA de Protozoário/genética , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Leishmania guyanensis/isolamento & purificação , Leishmania mexicana/isolamento & purificação , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Masculino , Tipagem Molecular , População Rural , Pele/parasitologia , Pele/patologia
11.
Free Radic Biol Med ; 129: 35-45, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30196081

RESUMO

Human leishmaniasis caused by Leishmania (Viannia) braziliensis can be presented as localized cutaneous leishmaniasis (LCL) or mucosal leishmaniasis (ML). Macrophages kill parasites using nitric oxide (NO) and reactive oxygen species (ROS). The aim of this study was to evaluate the ability of parasites obtained from patients with LCL or ML to produce and resist NO or ROS. Promastigotes and amastigotes from LCL or ML isolates produced similar amounts of NO in culture. Promastigotes from ML isolates were more resistant to NO and H2O2 than LCL parasites in a stationary phase, whereas amastigotes from LCL isolates were more resistant to NO. In addition, in the stationary phase, promastigote isolates from patients with ML expressed more thiol-specific antioxidant protein (TSA) than LCL isolates. Therefore it is suggested that infective promastigotes from ML isolates are more resistant to microbicidal mechanisms in the initial phase of infection. Subsequently, amastigotes lose this resistance. This behavior of ML parasites can decrease the number of parasites capable of stimulating the host immune response shortly after the infection establishment.


Assuntos
Antiprotozoários/farmacologia , Peróxido de Hidrogênio/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Óxido Nítrico/farmacologia , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Meios de Cultura/química , Feminino , Interações Hospedeiro-Parasita , Humanos , Imunidade Inata , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/isolamento & purificação , Leishmania braziliensis/metabolismo , Leishmaniose Tegumentar Difusa/imunologia , Leishmaniose Tegumentar Difusa/metabolismo , Leishmaniose Tegumentar Difusa/parasitologia , Leishmaniose Mucocutânea/imunologia , Leishmaniose Mucocutânea/metabolismo , Leishmaniose Mucocutânea/parasitologia , Estágios do Ciclo de Vida/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
12.
Pathog Dis ; 76(4)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29722820

RESUMO

Leishmania (Viannia) guyanensis is a causal agent of American tegumentary leishmaniasis (ATL). This protozoan has been poorly investigated; however, it can cause different clinical forms of ATL, ranging from a single cutaneous lesion to severe lesions that can lead to destruction of the nasopharyngeal mucosa. L. (V.) guyanensis and the disease caused by this species can present unique aspects revealing the need to better characterize this parasite species to improve our knowledge of the immunopathological mechanisms and treatment options for ATL. The mechanisms by which some patients develop a more severe form of ATL remain unclear. It is known that the host immune profile and parasite factors may influence the clinical manifestations of the disease. Besides intrinsic parasite factors, Leishmaniavirus RNA 1 (LRV1) infecting L. guyanensis can contribute to ATL immunopathogenesis. In this review, general aspects of L. guyanensis infection in humans and mouse models are presented.


Assuntos
Interações Hospedeiro-Parasita/imunologia , Leishmania guyanensis/patogenicidade , Leishmaniose Cutânea/patologia , Leishmaniavirus/patogenicidade , Membrana Mucosa/patologia , Animais , Modelos Animais de Doenças , Humanos , Imunidade Inata , Interleucina-17/biossíntese , Interleucina-17/imunologia , Leishmania guyanensis/imunologia , Leishmania guyanensis/virologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Leishmaniavirus/fisiologia , Camundongos , Membrana Mucosa/imunologia , Membrana Mucosa/parasitologia , Nasofaringe/imunologia , Nasofaringe/parasitologia , Nasofaringe/patologia , Índice de Gravidade de Doença
13.
Semin Immunol ; 38: 15-23, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29551246

RESUMO

Interleukin 32 (IL-32) is an intracellular cytokine produced by immune and non immune cells after different stimuli. It contributes to inflammation and control of intracellular pathogens mainly by inducing proinflammatory cytokines and microbicidal molecules. Evidence is rising showing that IL-32 can be considered an endogenous danger signal after tissue injury, amplifying the inflammatory process and acquired immune responses. It seems to be a master regulator of intracellular infectious diseases. In this review, first the general properties of IL-32 are described followed by its role in the immunopathogenesis of inflammatory and infectious diseases. Roles of IL-32 in the control of infectious diseases caused by intracellular pathogens are reported, and later a focus on IL-32 in leishmaniases, diseases caused by an intracellular protozoan, is presented.


Assuntos
Mediadores da Inflamação/imunologia , Interleucinas/imunologia , Espaço Intracelular/imunologia , Leishmania/imunologia , Leishmaniose/imunologia , Transdução de Sinais/imunologia , Animais , Citocinas/imunologia , Citocinas/metabolismo , Interações Hospedeiro-Parasita/imunologia , Humanos , Mediadores da Inflamação/metabolismo , Interleucinas/metabolismo , Espaço Intracelular/parasitologia , Leishmania/fisiologia , Leishmaniose/metabolismo , Leishmaniose/parasitologia
14.
Infect Immun ; 86(5)2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29483288

RESUMO

Visceral leishmaniasis (VL) is a chronic parasitic disease caused by Leishmania infantum in the Americas. During VL, several proinflammatory cytokines are produced in spleen, liver, and bone marrow. However, the role of interleukin-32 (IL-32) has not been explored in this disease. IL-32 can induce production of proinflammatory cytokines in innate immune cells and polarize the adaptive immune response. Herein, we discovered that L. infantum antigens induced expression of mRNA mainly for the IL-32γ isoform but also induced low levels of the IL-32ß transcript in human peripheral blood mononuclear cells. Furthermore, infection of human IL-32γ transgenic mice (IL-32γTg mice) with L. infantum promastigote forms increased IL-32γ expression in the spleen and liver. Interestingly, IL-32γTg mice harbored less parasitism in the spleen and liver than wild-type (WT) mice. In addition, IL-32γTg mice showed increased granuloma formation in the liver compared to WT mice. The protection against VL was associated with increased production of nitric oxide (NO), interferon gamma (IFN-γ), IL-17A, and tumor necrosis factor alpha by splenic cells restimulated ex vivo with L. infantum antigens. In parallel, there was an increase in the number of Th1 and Th17 T cells in the spleens of IL-32γTg mice infected with L. infantum IL-32γ induction of IFN-γ and IL-17A expression was found to be essential for NO production by splenic cells of infected animals. These data indicate that IL-32γ potentiates the Th1/Th17 immune response during experimental VL, thus contributing to the control of L. infantum infection.


Assuntos
Imunidade Inata/imunologia , Imunidade Inata/fisiologia , Interleucinas/imunologia , Interleucinas/fisiologia , Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Fatores de Proteção , Animais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Modelos Animais
15.
Infect Immun ; 86(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29311248

RESUMO

Cryptococcal species vary in capsule and cell size, thermotolerance, geographic distribution, and affected populations. Cryptococcus gattii sensu stricto and C. deuterogattii affect mainly immunocompetent hosts; however, C. bacillisporus, C. decagattii, and C. tetragattii cause infections mainly in immunocompromised hosts. This study aimed to compare the capacities of different species of the C. gattii species complex to induce cytokines and antimicrobial molecules in human peripheral blood mononuclear cells (PBMCs). Cryptococcus bacillisporus and C. deuterogattii induced the lowest levels of tumor necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), and IL-6 among the five species of the C. gattii complex. Cryptococcus deuterogattii induced higher levels of IL-22 than those induced by C. tetragattii and the environmental species C. flavescens In addition, C. bacillisporus and C. gattii sensu stricto proliferated inside human monocyte-derived macrophages after 24 h of infection. All Cryptococcus species were able to generate reactive oxygen species (ROS) in human PBMCs, with C. bacillisporus and C. deuterogattii being more efficient than the other species. In conclusion, C. bacillisporus and C. deuterogattii induce lower levels of the proinflammatory cytokines TNF-α, IL-1ß, and IL-6 and higher ROS levels than those induced by the other species. Species of the Cryptococcus gattii complex have different abilities to induce cytokine and ROS production by human PBMCs.


Assuntos
Criptococose/metabolismo , Criptococose/microbiologia , Cryptococcus gattii/fisiologia , Citocinas/metabolismo , Proliferação de Células , Humanos , Mediadores da Inflamação/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/microbiologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Modelos Biológicos , Espécies Reativas de Oxigênio/metabolismo
16.
Immunol Invest ; 47(1): 71-88, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29077524

RESUMO

Parkinson's disease (PD) is an age-related neurodegenerative disease characterized by loss of dopaminergic neurons associated with neuroinflammation. Toll-like receptors (TLRs) are expressed in peripheral blood leukocytes and also in neurons and glial cells mediating inflammation. This study aimed to investigate the peripheral blood leukocyte response to TLR2 and TLR4 agonists in young and elderly PD patients. Two groups of patients with PD were evaluated (≤ 55 years old and ≥ 65 years old), age-matched with healthy controls (n = 26). Severity of PD was evaluated by Unified Parkinson's Disease Rating Scale (UPDRS). Whole blood cultures were stimulated with lipopolysaccharide (LPS), a TLR4 agonist or Pam3Cys (Pam), a TLR2 agonist. Tumor necrosis factor alpha (TNFα) and interleukin 10 (IL-10) were measured by immunoenzimatic assay. 6 h-TNFα production was increased after TLR4 stimulation, mainly in young PD patients, whereas TLR2-induced TNFα and IL-10 levels were decreased in PD patients independent of age (p < 0.05). A reverse correlation between LPS-induced TNFα production and age was observed in PD patients and controls, but TNFα induced by TLR2 agonist was not associated with age of PD patients or controls. TNFα production induced by TLR4 but not by TLR2 was reversely associated with the age at PD onset and disease duration. No associations between UPDRS scores and cytokine levels were detected. In conclusion, TLR4 and TLR2 responses seem to be differentially affected during PD. Data suggest that TLR2 deficiency in periphery is independent of age of the patients, age at PD onset, or PD duration.


Assuntos
Fatores Etários , Envelhecimento/imunologia , Doença de Parkinson/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto , Idoso , Células Cultivadas , Humanos , Interleucina-10/metabolismo , Lipopolissacarídeos/imunologia , Lipoproteínas/imunologia , Pessoa de Meia-Idade , Risco , Receptor 2 Toll-Like/agonistas , Receptor 4 Toll-Like/agonistas , Fator de Necrose Tumoral alfa/metabolismo
17.
Parasitol Res ; 117(2): 419-427, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29270768

RESUMO

Because of visceral leishmaniasis (VL) urbanization and spreading of the human immunodeficiency virus (HIV) infection to rural areas, coinfection has become more common. Here, we compared the accuracy of Kalazar Detect® (KD), an rK39-based immunochromatographic (IC) test, and OrangeLife® (OL), an rK39 + rK28 IC test, for diagnosing VL in patients coinfected with HIV in an endemic area in Brazil. Seventy-six VL patients and 40 patients with other diseases, of which 31 and 21 patients, respectively, were infected with HIV, were examined. The sensitivity of OL and KD tests was 88.89 and 95.45%, respectively, in patients without HIV. The sensitivity dropped to 67.74 and 61.29%, respectively, in coinfected patients. The decrease in sensitivity was not related to a decrease in the production of Leishmania-specific IgG. Because of the low sensitivity of rk39 test in HIV-infected patients, we suggest that patients with negative rK39 results should undergo further investigation with additional serological tests that are not based only on the rK39 antigen and examination of bone marrow aspirates.


Assuntos
Cromatografia de Afinidade/métodos , Infecções por HIV/complicações , Leishmaniose Visceral/diagnóstico , Adulto , Antígenos de Protozoários/imunologia , Brasil , Coinfecção , Feminino , Humanos , Leishmaniose Visceral/complicações , Masculino , Proteínas de Protozoários/imunologia , Sensibilidade e Especificidade
18.
Sci Rep ; 7(1): 15219, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-29123157

RESUMO

American Tegumentary Leishmaniasis is a chronic infection caused by Leishmania protozoan. It is not known whether genetic variances in NOD-like receptor (NLR) family members influence the immune response towards Leishmania parasites and modulate intracellular killing. Using functional genomics, we investigated whether genetic variants in NOD1 or NOD2 influence the production of cytokines by human PBMCs exposed to Leishmania. In addition, we examined whether recognition of Leishmania by NOD2 contributes to intracellular killing. Polymorphisms in the NOD2 gene decreased monocyte- and lymphocyte-derived cytokine production after stimulation with L. amazonensis or L. braziliensis compared to individuals with a functional NOD2 receptor. The phagolysosome formation is important for Leishmania-induced cytokine production and upregulation of NOD2 mRNA expression. NOD2 is crucial to control intracellular infection caused by Leishmania spp. NOD2 receptor is important for Leishmania recognition, the control of intracellular killing, and the induction of innate and adaptive immune responses.


Assuntos
Leishmania/imunologia , Leishmaniose Cutânea/imunologia , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Polimorfismo Genético , Adulto , Idoso , Sobrevivência Celular , Células Cultivadas , Citocinas/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Países Baixos , Fagossomos/metabolismo , Adulto Jovem
19.
Pathog Dis ; 75(7)2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28830073

RESUMO

Platelet-activating factor (PAF) is produced by macrophages during inflammation and infections. We evaluated whether PAF is able to modulate the infection of human macrophages by Leishmania braziliensis, the main Leishmania sp. in Brazil. Monocyte-derived macrophages were incubated with promastigote forms in absence or presence of exogenous PAF. We observed that the treatment of macrophages with low concentrations of PAF prior to infection increased the phagocytosis of L. braziliensis. More importantly, exogenous PAF reduced the parasitism when it was added before, during or after infection. In addition, treatment with a PAF antagonist (PCA 4248) resulted in a significant increase of macrophage infection in a concentration-dependent manner, suggesting that endogenous PAF is important to control L. braziliensis infection. Mechanistically, while exogenous PAF increased production of reactive oxygen species (ROS) treatment with PCA 4248 reduced oxidative burst during L. braziliensis infection. The microbicidal effects of exogenous PAF were abolished when macrophages were treated with apocynin, an NADPH oxidase inhibitor. The data show that PAF promotes the production of ROS induced by L. braziliensis, suggesting that this lipid mediator may be relevant to control L. braziliensis infection in human macrophages.


Assuntos
Leishmania braziliensis/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Fator de Ativação de Plaquetas/farmacologia , Espécies Reativas de Oxigênio/agonistas , Acetofenonas/farmacologia , Di-Hidropiridinas/farmacologia , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Humanos , Leishmania braziliensis/crescimento & desenvolvimento , Macrófagos/imunologia , Macrófagos/parasitologia , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Fator de Ativação de Plaquetas/antagonistas & inibidores , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória/efeitos dos fármacos
20.
Parasit Vectors ; 10(1): 336, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28709468

RESUMO

BACKGROUND: Interleukin 32 (IL-32) is a pro-inflammatory cytokine induced in patients with American tegumentary leishmaniasis (ATL) caused by Leishmania braziliensis. Here, we investigated whether IL-32 is also expressed in patient lesions caused by L. amazonensis. In addition, we evaluated experimental L. amazonensis and L. braziliensis infections in C57BL/6 transgenic mice for human IL-32γ (IL-32γTg) in comparison with wild-type (WT) mice that do not express the IL-32 gene. RESULTS: Human cutaneous lesions caused by L. amazonensis express higher levels of IL-32 than healthy control skin. In mice, the presence of IL-32γ promoted the control of cutaneous lesions caused by L. braziliensis, but not lesions caused by L. amazonensis in an ear dermis infection model. In addition, IL-32γTg mice displayed less tissue parasitism and inflammation in IL-32γTg than WT mice during the healing phase of L. braziliensis infection. Production of antigen-specific pro-inflammatory cytokines was higher in IL-32γTg mice than in WT mice during L. braziliensis infection but not during L. amazonensis infection. CONCLUSIONS: Human cutaneous lesions caused by L. amazonensis express high levels of IL-32. In mice, the presence of IL-32γ contributes to the lesion healing caused by L. braziliensis but not by L. amazonensis. Data suggest that despite the ability for both species to induce IL-32 in humans, the connections between this cytokine and other immune players induced by related species of parasites can lead to distinct outcomes of the murine infections.


Assuntos
Interleucinas/metabolismo , Leishmania braziliensis/imunologia , Leishmania mexicana/imunologia , Leishmaniose Cutânea/imunologia , Cicatrização , Animais , Modelos Animais de Doenças , Humanos , Interleucinas/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pele/parasitologia , Pele/patologia
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