RESUMO
The release of biomolecules critically affects all pathogens and their establishment of diseases. For the export of several biomolecules in diverse species, the use of extracellular vesicles (EVs) is considered to represent an alternative transport mechanism, but no study to date has investigated EVs from dermatophytes. Here, we describe biologically active EVs from the dermatophyte Trichophyton interdigitale, a causative agent of mycoses worldwide. EV preparations from T. interdigitale were examined using nanoparticle-tracking analysis, which revealed vesicular structures 20-380 nm in diameter. These vesicles induced the production of proinflammatory mediators by bone marrow-derived macrophages (BMDMs) and keratinocytes in a dose-dependent manner, and an addition of the EVs to BMDMs also stimulated the transcription of the M1-polarization marker iNOS (inducible nitric oxide synthase) and diminished the expression of the M2 markers arginase-1 and Ym-1. The observed M1 macrophages' polarization triggered by EVs was abolished in cells obtained from knockout Toll-like receptor-2 mice. Also, the EVs-induced productions of pro-inflammatory mediators were blocked too. Furthermore, the EVs from T. interdigitale enhanced the fungicidal activity of BMDMs. These results suggest that EVs from T. interdigitale can modulate the innate immune response of the host and influence the interaction between T. interdigitale and host immune cells. Our findings thus open new areas of investigation into the host-parasite relationship in dermatophytosis.
Assuntos
Vesículas Extracelulares/metabolismo , Queratinócitos/imunologia , Queratinócitos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Tinha/imunologia , Tinha/microbiologia , Trichophyton/imunologia , Trichophyton/metabolismo , Animais , Biomarcadores , Citocinas/metabolismo , Modelos Animais de Doenças , Imunomodulação , Imunofenotipagem , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Knockout , Óxido Nítrico/metabolismo , Fagocitose/imunologiaRESUMO
Dermatophytosis is one of the most common human infections affecting both immunocompetent individuals and immunocompromised patients, in whom the disease is more aggressive and can reach deep tissues. Over the last decades, cases of deep dermatophytosis have increased and the dermatophyte-host interplay remains poorly investigated. Pattern recognition molecules, such as Toll-like receptors (TLR), play a crucial role against infectious diseases. However, there has been very little research reported on dermatophytosis. In the present study, we investigated the role of TLR2 during the development of experimental deep dermatophytosis in normal mice and mice with alloxan-induced diabetes mellitus, an experimental model of diabetes that exhibits a delay in the clearance of the dermatophyte, Trichophyton mentagrophytes (Tm). Our results demonstrated that inoculation of Tm into the footpads of normal mice increases the expression of TLR2 in CD115+Ly6Chigh blood monocytes and, in hypoinsulinemic-hyperglycemic (HH) mice infected with Tm, the increased expression of TLR2 was exacerbated. To understand the role of TLR2 during the development of murine experimental deep dermatophytosis, we employed TLR2 knockout mice. Tm-infected TLR2-/- and TLR2+/+ wild-type mice exhibited similar control of deep dermatophytic infection and macrophage activity; however, TLR2-/- mice showed a noteworthy increase in production of IFN-γ, IL-10, and IL-17, and an increased percentage of splenic CD25+Foxp3+ Treg cells. Interestingly, TLR2-/- HH-Tm mice exhibited a lower fungal load and superior organization of tissue inflammatory responses, with high levels of production of hydrogen peroxide by macrophages, alongside low TNF-α and IL-10; high production of IL-10 by spleen cells; and increased expansion of Tregs. In conclusion, we demonstrate that TLR2 diminishes the development of adaptive immune responses during experimental deep dermatophytosis and, in a diabetic scenario, acts to intensify a non-protective inflammatory response.
Assuntos
Complicações do Diabetes , Tinha/imunologia , Receptor 2 Toll-Like/deficiência , Trichophyton/imunologia , Animais , Contagem de Colônia Microbiana , Citocinas/metabolismo , Modelos Animais de Doenças , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Reguladores/imunologiaRESUMO
Diversity in the macrophage models currently employed in immunology studies may lead to opposed results and interpretations. In this study, we aimed to analyze the suitability of J774 macrophage-like cells as a model for the interaction between the dermatophyte Trichophyton rubrum and macrophages. J774 cells were competent in fungal phagocytosis, but succumbed to hyphal growth. Nevertheless, they could also secrete IL-1ß in response to the dermatophyte. On the opposite direction, inflammatory, thioglycollate-induced peritoneal macrophages did not succumb to fungal growth and showed no significant IL-1ß production. The proteomic profiling of these cells uncovered vimentin and plastin-2 as proteins whose abundance was altered by the fungal interaction. Our study indicates that this cell line could be an interesting tool in the investigation of T. rubrum infection biology.
Assuntos
Macrófagos/imunologia , Macrófagos/microbiologia , Trichophyton/imunologia , Animais , Células Cultivadas , Camundongos Endogâmicos C57BL , Modelos Biológicos , Tinha/imunologia , Tinha/microbiologiaRESUMO
Dermatophytoses are chronic fungal infections, the main causative agent of which is Trichophyton rubrum (T. rubrum). Despite their high occurrence worldwide, the immunological mechanisms underlying these diseases remain largely unknown. Here, we uncovered the C-type lectin receptors, Dectin-1 and Dectin-2, as key elements in the immune response to T. rubrum infection in a model of deep dermatophytosis. In vitro, we observed that deficiency in Dectin-1 and Dectin-2 severely compromised cytokine production by dendritic cells. In vivo, mice lacking Dectin-1 and/or Dectin-2 showed an inadequate pro-inflammatory cytokine production in response to T. rubrum infection, impairing its resolution. Strikingly, neither adaptive immunity nor IL-17 response were required for fungal clearance, highlighting innate immunity as the main checkpoint in the pathogenesis of T. rubrum infection.
Assuntos
Células Dendríticas/imunologia , Lectinas Tipo C/metabolismo , Tinha/imunologia , Trichophyton/imunologia , Imunidade Adaptativa , Animais , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Humanos , Imunidade , Interleucina-17/metabolismo , Lectinas Tipo C/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , RNA Interferente Pequeno/genéticaRESUMO
Dermatophytosis are one of the most common fungal infections in the world. They compromise keratinized tissues and the main etiological agent is Trichophyton rubrum. Macrophages are key cells in innate immunity and prominent sources of IL-1ß, a potent inflammatory cytokine whose main production pathway is by the activation of inflammasomes and caspase-1. However, the role of inflammasomes and IL-1 signaling against T.rubrum has not been reported. In this work, we observed that bone marrow-derived macrophages produce IL-1ß in response to T.rubrum conidia in a NLRP3-, ASC- and caspase-1-dependent fashion. Curiously, lack of IL-1 signaling promoted hyphae development, uncovering a protective role for IL-1ß in macrophages. In addition, mice lacking IL-1R showed reduced IL-17 production, a key cytokine in the antifungal defense, in response to T.rubrum. Our findings point to a prominent role of IL-1 signaling in the immune response to T.rubrum, opening the venue for the study of this pathway in other fungal infections.
Assuntos
Interleucina-17/imunologia , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Transdução de Sinais , Trichophyton/imunologia , Trichophyton/fisiologia , Animais , Feminino , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Inflamassomos/imunologia , Interleucina-17/metabolismo , Interleucina-1beta/química , Interleucina-1beta/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Macrófagos/ultraestrutura , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Tinha/imunologia , Tinha/prevenção & controleRESUMO
Dermatophytes are the most common agents of superficial mycoses that are caused by mold fungi. Trichophyton rubrum is the most common pathogen causing dermatophytosis. The immunology of dermatophytosis is currently poorly understood. Recently, our group investigated the interaction of T. rubrum conidia with peritoneal mouse macrophages. We found that macrophages phagocytose T. rubrum conidia resulted in a down-modulation of class II major histocompatibility complex (MHC) antigens and in the expression of co-stimulatory molecules. Furthermore, it induced the production of IL-10, and T. rubrum conidia differentiated into hyphae that grew and killed the macrophages after 8 hrs of culture. This work demonstrated that dendritic cells (DCs) and macrophages, from patients or normal individuals, avidly interact with pathogenic fungus T. rubrum. The dermatophyte has two major receptors on human monocyte-derived DC: DC-SIGN and mannose receptor. In contrast macrophage has only mannose receptor that participates in the phagocytosis or bound process. Another striking aspect of this study is that unlike macrophages that permit rapid growth of T. rubrum, human DC inhibited the growth and induces Th activation. The ability of DC from patients to interact and kill T. rubrum and to present Ags to T cells suggests that DC may play an important role in the host response to T. rubrum infection by coordinating the development of cellular immune response.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Tinha/imunologia , Trichophyton/imunologia , Adulto , Idoso , Animais , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Citocinas/metabolismo , Células Dendríticas/metabolismo , Feminino , Humanos , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Tinha/metabolismo , Tinha/microbiologiaRESUMO
Dermatophytes invade the stratum corneum of the skin and other keratinized tissues such as hair and nails, and Trichophyton rubrum causes approximately 80% of cutaneous mycoses in humans. To evaluate the cellular immune response of patients with extensive dermatophytosis caused by T. rubrum, we evaluated lymphocyte populations, the lymphoproliferative response to: phytohaemagglutinin (PHA); anti-CD3 (OKT3); and pokeweed mitogen (PWM), Candida sp. (CMA), an extract of T. rubrum, and the main fungal epitope TriR2 (T). We also evaluated interleukin (IL)-4, IL-10, IL-12 and IFN-γ after stimulation by PHA, CMA and TriR2. The immunophenotyping showed no differences between patients and controls. The lymphoproliferation test showed significant differences between the groups stimulated by PWM and CMA, as well as against TriR2, being significantly higher for the control group. Conversely, there were similar results for the groups after stimulation by the extract. The cytokines' quantification showed a significant difference between the groups only for IFN-γ stimulated by PHA and TriR2. We can conclude that the fungal extract can stimulate lymphoproliferation by both groups' lymphocytes. However, the response to Tri r2 was more specific. We showed that some patients with extensive dermatophytosis have normal cellular response, recognising both the extract and TriR2.
Assuntos
Imunidade Celular , Tinha/imunologia , Trichophyton/imunologia , Antígenos de Fungos/imunologia , Candida/imunologia , Estudos de Casos e Controles , Proliferação de Células , Epitopos/imunologia , Seguimentos , Humanos , Imunofenotipagem , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-4/imunologia , Ativação Linfocitária , Contagem de Linfócitos , Muromonab-CD3/imunologia , Fito-Hemaglutininas/imunologia , Mitógenos de Phytolacca americana/imunologia , Tinha/microbiologiaRESUMO
Recognizing the invasive potential of the dermatophytes and understanding the mechanisms involved in this process will help with disease diagnosis and with developing an appropriate treatment plan. In this report, we present the histopathological, microbiological and immunological features of a model of invasive dermatophytosis that is induced by subcutaneous infection of Trichophyton mentagrophytes in healthy adult Swiss mice. Using this model, we observed that the fungus rapidly spreads to the popliteal lymph nodes, spleen, liver and kidneys. Similar to the human disease, the lymph nodes were the most severely affected sites. The fungal infection evoked acute inflammation followed by a granulomatous reaction in the mice, which is similar to what is observed in patients. The mice were able to mount a Th1-polarized immune response and displayed IL-10-mediated immune regulation. We believe that the model described here will provide valuable information regarding the dermatophyte-host relationship and will yield new perspective for a better understanding of the immunological and pathological aspects of invasive dermatophytosis.
Assuntos
Antígenos de Fungos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Interleucina-10/imunologia , Tinha/imunologia , Trichophyton/imunologia , Animais , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Injeções Subcutâneas , Interleucina-10/metabolismo , Rim/imunologia , Rim/microbiologia , Fígado/imunologia , Fígado/microbiologia , Linfonodos/imunologia , Linfonodos/microbiologia , Masculino , Camundongos , Pele/imunologia , Pele/microbiologia , Baço/imunologia , Baço/microbiologia , Células Th1/imunologia , Fatores de Tempo , Tinha/microbiologia , Tinha/patologia , Trichophyton/crescimento & desenvolvimento , Trichophyton/fisiologiaRESUMO
Many works have shown that the enhanced susceptibility to infection seen in diabetic patients can be related to the hyperglycemia-hypoinsulinemia (HH) observed in this condition. Herein, we evaluated the HH effects on the morphofunctional features of the thymus as well as on dermatophytic infection. We demonstrated that, not only the HH condition but also the dermatophytic infection induced transitory alterations in the thymus; it was characterized by loss of cortical-medullar definition and disorganization of the extracellular matrix. These mice also showed a decrease of CD4(+) CD8(+) thymocytes and a higher percentage of CD4(+) CD8(+) lymphocytes in the peripheral blood. After 7 days, the thymus and peripheral lymphocytes subsets returned to normal values. Interestingly, when the two conditions, HH condition and the infection, were associated, the mice showed a decrease in the percentage of CD4(+) CD8(-) blood lymphocytes that are involved in the modulation of immune response and have direct cytotoxic effects on the fungus. Taken together, our results showed that both conditions transitorily changed the thymus, but only when both these conditions are present do they trigger persistent changes that might be responsible for the higher susceptibility to dermatophytosis seen in HH patients.
Assuntos
Dermatomicoses/imunologia , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/imunologia , Subpopulações de Linfócitos T/imunologia , Timo/imunologia , Trichophyton/patogenicidade , Aloxano/administração & dosagem , Animais , Dermatomicoses/complicações , Citometria de Fluxo , Humanos , Camundongos , Camundongos Obesos , Subpopulações de Linfócitos T/citologia , Trichophyton/imunologiaRESUMO
A 33 year-old HIV-positive Brazilian female patient was diagnosed with a cutaneous inflammatory reaction on her left forearm. The lesion spread rapidly affecting most of her forearm. The clinical diagnosis of tinea corporis (ringworm) was confirmed by wet mount preparations on 20% KOH and by the isolation of Trichophyton rubrum on pure cultures. Treatment with Fluconazole for a period of four weeks successfully cured the infection.