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1.
PLoS Negl Trop Dis ; 14(8): e0008550, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841284

RESUMO

BACKGROUND: Leishmanin Skin Test (LST) is considered as a useful indicator of past infection by Leishmania parasites. However, the temporal dynamics of a positive LST under different epidemiologic scenarios and whether it relates to the protection against the recurrence of an overt disease are not fully documented. METHODOLOGY/PRINCIPAL FINDINGS: We report here on a population based prospective study conducted on 2686 individuals living in two foci located in Central Tunisia, to assess over a one-year epidemiologic season, the incidence of Leishmania (L.) major infection and disease and changes in LST reactivity. The two foci were both endemic for Cutaneous Leishmaniasis (CL) due to L. major, but contrasted in their history for this disease (ie: an old focus versus a recent focus). We found that most infections occurred in the new focus (290/1000; 95% CI: 265-315 person-years) with an incidence rate of CL lesions 2.4 times higher than in the old focus. Likewise, the rates of LST reactivity reversion and loss, in the new focus, were 99/1000[38-116] person-years and 14/1000[8-21] person-years, respectively. Loss of LST reactivity was not noticed in the old focus. Interestingly, the incidence rates of symptomatic infection did not differ significantly according to the LST status at enrolment (negative versus positive) between the combined foci and the new one. CONCLUSIONS/SIGNIFICANCE: Our findings confirm LST as a good tool for assessing L. major cryptic infection. However, the instability of the LST positivity in new foci should be considered as an important confounder of the outcome of this infection when developing a research protocol for vaccine trial.


Assuntos
Leishmania major/imunologia , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/imunologia , Testes Cutâneos/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tunísia/epidemiologia , Adulto Jovem
2.
Mem Inst Oswaldo Cruz ; 115: e200067, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667458

RESUMO

BACKGROUND Unfortunately, no any vaccine against leishmaniasis has been developed for human use. Therefore, a vaccine based on total Leishmania antigens could be a good and economic approach; and there are different methodologies to obtain these antigens. However, it is unknown whether the method to obtain the antigens affects the integrity and immune response caused by them. OBJECTIVES to compare the protein profile and immune response generated by total L. amazonensis antigens (TLA) produced by different methods, as well as to analyse the immune response and protection by a first-generation vaccine formulated with sonicated TLA (sTLA) and polyinosinic:polycytidylic acid [Poly (I:C)]. METHODS TLA were obtained by four different methodologies and their integrity and immune response were evaluated. Finally, sTLA was formulated with Poly (I:C) and their protective immune response was measured. FINDINGS sTLA presented a conserved protein profile and induced a strong immune response. In addition, Poly (I:C) improved the immune response generated by sTLA. Finally, sTLA + Poly (I:C) formulation provided partial protection against L. amazonensis infection. MAIN CONCLUSIONS The protein profile and immune response depend on the methodology used to obtain the antigens. Also, the formulation sTLA + Poly (I:C) provides partial protection against cutaneous leishmaniasis in mice.


Assuntos
Leishmania , Vacinas contra Leishmaniose , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/prevenção & controle , Vacinas Protozoárias/imunologia , Receptor 3 Toll-Like/imunologia , Animais , Antígenos de Protozoários/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C
3.
Parasite Immunol ; 42(9): e12759, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32460372

RESUMO

AIMS: The aim of this study was to evaluate characteristics of B cells in human tegumentary leismaniasis (TL) analysing cutaneous leishmaniasis (CL), most prevalent form and mucosal leishmaniasis (ML), aggressive form characterized by the destruction of the oral-nasal-pharyngeal cavities. METHODS AND RESULTS: By flow cytometry analysis, we found decreased percentages of non-class-switched memory B cells in TL with the degree of the loss related to clinical severity. Using commercial ELISA, we reported high levels of B-cell activating factor (BAFF) and IgG preferentially in aggressive CL and markedly in ML together with decreased BAFF receptors in the latter. We also found lower levels of BAFF after clinical recovery suggesting a relation between BAFF and disease activity. Mucosal leishmaniasis history of therapeutic failure presented high levels of BAFF accompanied by detectable concentrations of IFN-γ and IL-6 (assayed by commercial ELISA and cytometric bead arrays respectively), cytokines involved in exaggerated inflammatory responses and tissue damage in TL. CONCLUSION: We demonstrate B-cell disturbances in TL with the degree of the alterations related to clinical severity. We suggest a relation between excess of BAFF and disease activity and point towards a possible implication of BAFF in the inflammatory phenomenon of ML.


Assuntos
Fator Ativador de Células B/metabolismo , Linfócitos B/imunologia , Leishmaniose Cutânea/imunologia , Adolescente , Adulto , Idoso , Receptor do Fator Ativador de Células B/metabolismo , Citocinas/metabolismo , Feminino , Humanos , Imunoglobulina G/imunologia , Leishmaniose Mucocutânea/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Immunology ; 159(4): 355-356, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32182636

RESUMO

Both CD8+ T cells and NK cells contribute to the immune response against the protozoan Leishmania parasite. Both are able to generate IFN-γ and both display cytotoxic features. These features may enable them to not only contribute to parasite clearance but also to cause immune-mediated pathology. This pathology is evident, for example, in the Leismania-induced skin lesions found in patients with cutaneous leismaniasis (CL). Here we highlight new data demonstrating that CD8+ T cells and NK cells in CL display a highly cytotoxic senescent phenotype, and that the senescent T cells play a major role in mediating skin pathology. This is the first demonstration that senescent CD8 T cells contribute to immunopathology in vivo.


Assuntos
Citotoxicidade Imunológica , Leishmania braziliensis/patogenicidade , Leishmaniose Cutânea/patologia , Pele/patologia , Linfócitos T Citotóxicos/patologia , Antígenos CD57/genética , Antígenos CD57/imunologia , Senescência Celular/imunologia , Expressão Gênica , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Interferon gama/genética , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/parasitologia , Células Matadoras Naturais/patologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Oligossacarídeos/genética , Oligossacarídeos/imunologia , Antígeno Sialil Lewis X/análogos & derivados , Antígeno Sialil Lewis X/genética , Antígeno Sialil Lewis X/imunologia , Pele/imunologia , Pele/parasitologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/parasitologia
5.
PLoS Negl Trop Dis ; 14(3): e0008093, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32176691

RESUMO

Human leishmaniasis is a public health problem worldwide for which the development of a vaccine remains a challenge. T cell-mediated immune responses are crucial for protection. Peptide vaccines based on the identification of immunodominant T cell epitopes able to induce T cell specific immune responses constitute a promising strategy. Here, we report the identification of human leukocyte antigen class-I (HLA-I) and -II (HLA-II)-restricted multi-epitope peptides from Leishmania proteins that we have previously described as vaccine candidates. Promastigote Surface Antigen (PSA), LmlRAB (L. major large RAB GTPase) and Histone (H2B) were screened, in silico, for T cell epitopes. 6 HLA-I and 5 HLA-II-restricted multi-epitope peptides, able to bind to the most frequent HLA molecules, were designed and used as pools to stimulate PBMCs from individuals with healed cutaneous leishmaniasis. IFN-γ, IL-10, TNF-α and granzyme B (GrB) production was evaluated by ELISA/CBA. The frequency of IFN-γ-producing T cells was quantified by ELISpot. T cells secreting cytokines and memory T cells were analyzed by flow cytometry. 16 of 25 peptide pools containing HLA-I, HLA-II or HLA-I and -II peptides were able to induce specific and significant IFN-γ levels. No IL-10 was detected. 6 peptide pools were selected among those inducing the highest IFN-γ levels for further characterization. 3/6 pools were able to induce a significant increase of the percentages of CD4+IFN-γ+, CD8+IFN-γ+ and CD4+GrB+ T cells. The same pools also induced a significant increase of the percentages of bifunctional IFN-γ+/TNF-α+CD4+ and/or central memory T cells. We identified highly promiscuous HLA-I and -II restricted epitope combinations from H2B, PSA and LmlRAB proteins that stimulate both CD4+ and CD8+ T cell responses in recovered individuals. These multi-epitope peptides could be used as potential components of a polytope vaccine for human leishmaniasis.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Leishmania/imunologia , Leishmaniose Cutânea/imunologia , Proteínas Recombinantes de Fusão/imunologia , Adulto , Antígenos de Protozoários/genética , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito T/genética , Feminino , Citometria de Fluxo , Granzimas/análise , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Interferon gama/análise , Interleucina-10/análise , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fator de Necrose Tumoral alfa/análise , Voluntários , Adulto Jovem
6.
PLoS One ; 15(3): e0229400, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32203546

RESUMO

The pathogenesis of cutaneous leishmaniasis (CL) caused by Leishmania (Viannia) braziliensis is dictated mainly by the immune-mediated-tissue inflammation developed. The understanding of the immunological mechanisms that generate tissue damage or resolution of lesions is the key to the development of effective vaccine protocols and proper therapeutic schemes. It is clear that the specific immune response mediated by T cells is responsible for the beneficial outcome of the disease, however, the roles of CD4+ T, CD8+ T, NK and NKT cell subpopulations in immunopathogenesis of CL need to be elucidated. Peripheral blood cells from patients before, during and after the antimonial therapy, as well as healthy individuals (HI) were cultured with (LbAgS) or without (NS) L. braziliensis antigens (LbAg). Afterwards, the frequencies of LbAg-specific-cytotoxic CD8+ T, CD4+ T, NK and CD3+CD56+ NKT cells, as well as their activation and exhaustion profiles, were defined by flow cytometry. We observed higher frequencies of CD8+ T, NK and CD3+CD56+ NKT cells and lower frequencies of CD4+ T lymphocytes in LbAgS cell cultures from patients before treatment. The specific response to LbAg resulted in an expansion of cytotoxic-activated CD4+ T, CD8+ T, and NK cells, before and during treatment, indicating specificity in the response by these cells against L. braziliensis. Furthermore, comparing the differences of frequencies of cytotoxic-activated CD4+T, CD8+T, and NK cells, among before and during treatment patients and HI groups, we conclude that these cell populations are in charge of immune response elicited by antimonial therapy. Interestingly, we also observed that NK cells were induced by LbAg to an exhaustion profile during all clinical stages of the disease. The increased antigen-specific activation and cytotoxic activity are in line with the strong inflammatory response described in this disease, a likely cause of tissue damage. These findings reinforce the involvement of these distinct cytotoxic-activated cell populations in the immunopathogenesis of CL, showing a character of specificity in this immune response.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Matadoras Naturais/imunologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Adulto , Idoso , Complexo CD3/metabolismo , Antígeno CD56/metabolismo , Citocinas/metabolismo , Feminino , Humanos , Leishmaniose Cutânea/parasitologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Citotóxicos , Adulto Jovem
7.
J Vis Exp ; (156)2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32150165

RESUMO

Leishmania spp. are protozoan parasites that cause leishmaniases, diseases that present a wide spectrum of clinical manifestations from cutaneous to visceral lesions. Currently, 12 million people are estimated to be infected with Leishmania worldwide and over 1 billion people live at the risk of infection. Leishmania amazonensis is endemic in Central and South America and usually leads to the cutaneous form of the disease, which can be directly visualized in an animal model. Therefore, L. amazonensis strains are good models for cutaneous leishmaniasis studies because they are also easily cultivated in vitro. C57BL/6 mice mimic the L. amazonensis-driven disease progression observed in humans and are considered one of the best mice strains model for cutaneous leishmaniasis. In the vertebrate host, these parasites inhabit macrophages despite the defense mechanisms of these cells. Several studies use in vitro macrophage infection assays to evaluate the parasite infectivity under different conditions. However, the in vitro approach is limited to an isolated cell system that disregards the organism's response. Here, we compile an in vivo murine infection method that provides a systemic physiological overview of the host-parasite interaction. The detailed protocol for the in vivo infection of C57BL/6 mice with L. amazonensis comprises parasite differentiation into infective amastigotes, mice footpad cutaneous inoculation, lesion development, and parasite load determination. We propose this well-established method as the most adequate method for physiological studies of the host immune and metabolic responses to cutaneous leishmaniasis.


Assuntos
Modelos Animais de Doenças , Interações Hospedeiro-Parasita/imunologia , Leishmania/imunologia , Leishmania/patogenicidade , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Virulência , Animais , Feminino , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL
8.
Infect Immun ; 88(5)2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32094254

RESUMO

Localized skin lesions are characteristic of cutaneous leishmaniasis (CL); however, Leishmania (Viannia) species, which are responsible for most CL cases in the Americas, can spread systemically, sometimes resulting in mucosal disease. Detection of Leishmania has been documented in healthy mucosal tissues (conjunctiva, tonsils, and nasal mucosa) and healthy skin of CL patients and in individuals with asymptomatic infection in areas of endemicity of L (V) panamensis and L (V) braziliensis transmission. However, the conditions and mechanisms that favor parasite persistence in healthy mucosal tissues are unknown. In this descriptive study, we compared the cell populations of the nasal mucosa (NM) of healthy donors and patients with active CL and explored the immune gene expression signatures related to molecular detection of Leishmania in this tissue in the absence of clinical signs or symptoms of mucosal disease. The cellular composition and gene expression profiles of NM samples from active CL patients were similar to those of healthy volunteers, with a predominance of epithelial over immune cells, and within the CD45+ cell population, a higher frequency of CD66b+ followed by CD14+ and CD3+ cells. In CL patients with molecular evidence of Leishmania persistence in the NM, genes characteristic of an anti-inflammatory and tissue repair responses (IL4R, IL5RA, POSTN, and SATB1) were overexpressed relative to NM samples from CL patients in which Leishmania was not detected. Here, we report the first immunological description of subclinically infected NM tissues of CL patients and provide evidence of a local anti-inflammatory environment favoring parasite persistence in the NM.


Assuntos
Leishmaniose Cutânea/imunologia , Mucosa Nasal/imunologia , Adulto , Antígenos CD/imunologia , Moléculas de Adesão Celular/imunologia , Feminino , Humanos , Subunidade alfa de Receptor de Interleucina-4/imunologia , Subunidade alfa de Receptor de Interleucina-5/imunologia , Leishmania/imunologia , Masculino , Proteínas de Ligação à Região de Interação com a Matriz/imunologia , Pele/imunologia , Transcriptoma/imunologia
9.
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
10.
Exp Parasitol ; 210: 107846, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32001303

RESUMO

Leishmaniasis is a neglected disease caused by an intracellular protozoan parasite of the genus Leishmania. Infection starts when this protozoan replicates in a phagolysosomal compartment in macrophages, after evading host immune responses. The balance of Th1 and Th2 immune responses is crucial in leishmaniasis because it will determine whether the infection will be under control or if clinical complications will occur. The inflammasome, which is activated during Leishmania infection, involves the action of caspase-1 and release of the proinflammatory cytokines interleukin-1ß and interleukin-18. Together, they contribute to the maintenance of an inflammatory response and pyroptosis. Here, we evaluated the serum levels of cytokines and the expression of circulating microRNAs related to inflammasome regulation in twenty-seven patients with cutaneous leishmaniasis in comparison to nine healthy individuals, in the context of the inflammasome activation. Evaluation of serum cytokines activation (IL-1ß, IL-2, IL-4, IL-6, IL-10, and IL-17) was performed by flow cytometry using CBA kits (cytometric beads array) while the expression of circulating microRNAs (miR-7, miR-133a, miR-146b, miR-155, miR-223, miR-328, and miR-342) in plasma was measured by quantitative polymerase chain reaction. Our results showed an increase of the expression of miR-7-5p (p < 10-5), miR-133a (p = 0.034), miR-146b (p = 0.003), miR-223-3p (p = 10-5), and miR-328-3p (p = 0.002), and cytokine levels for IL-1ß (p = 0.0005), IL-6 (p = 0.001), and IL-17 (p = 0.001) in patients with cutaneous leishmaniasis compared to the controls. These results suggest that microRNAs and cytokines can play an important role in regulating the human immune responses to Leishmania infection. Our findings may contribute to the understanding of the mechanisms of the gene regulation during the cutaneous leishmaniasis and to the identification of possible biomarkers of the infection.


Assuntos
Citocinas/sangue , Inflamassomos/genética , Leishmaniose Cutânea/genética , MicroRNAs/fisiologia , Adulto , Idoso , Brasil , Estudos de Casos e Controles , Biologia Computacional , Feminino , Humanos , Inflamassomos/imunologia , Interleucina-17/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Leishmaniose Cutânea/sangue , Leishmaniose Cutânea/imunologia , Masculino , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , População Rural , População Urbana , Adulto Jovem
11.
Immunology ; 159(4): 429-440, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31925782

RESUMO

Cytotoxic activity mediated by CD8+ T cells is the main signature of the immunopathogenesis of cutaneous leishmaniasis (CL). Here, we performed a broad evaluation of natural killer (NK) cell phenotypic and functional features during cutaneous leishmaniasis. We demonstrate for the first time that CL patients present the accumulation of circulating NK cells with multiple features of replicative senescence including low proliferative capacity and shorter telomeres, elevated expression of CD57, KLRG1 but diminished CD27 stimulatory receptor expression. Moreover, they exhibited higher cytotoxic and inflammatory potential than age-matched controls. The accumulation of circulating senescent NK cells (CD56dim  CD57bright ) correlated positively with skin lesion size in the same patients, suggesting that they, like circulating senescent CD8+ T cells, may contribute to the immunopathology of CL. However, this senescent population had lower cutaneous lymphocyte antigen expression and so had diminished skin-homing potential compared with total or senescent CD8+ T cells. This was confirmed in CL skin lesions where we found a predominance of CD8+ T cells (both senescent and non-senescent) that correlated with the severity of the disease. Although there was also a correlation between the proportions of senescent NK cells (CD56+  CD57+ ) in the skin and lesion size, this was less evident. Collectively our results demonstrate first-hand that senescent cytotoxic cells may mediate skin pathology during human cutaneous leishmaniasis. However, as senescent cytotoxic CD8+ T cells predominate in the skin lesions, they may have a greater role than NK cells in mediating the non-specific skin damage in CL.


Assuntos
Citotoxicidade Imunológica , Células Matadoras Naturais/patologia , Leishmania braziliensis/patogenicidade , Leishmaniose Cutânea/patologia , Pele/patologia , Linfócitos T Citotóxicos/patologia , Antígeno CD56/genética , Antígeno CD56/imunologia , Antígenos CD57/genética , Antígenos CD57/imunologia , Estudos de Casos e Controles , Senescência Celular/imunologia , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Interferon gama/genética , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/parasitologia , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Leishmania braziliensis/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Masculino , Oligossacarídeos/genética , Oligossacarídeos/imunologia , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Índice de Gravidade de Doença , Antígeno Sialil Lewis X/análogos & derivados , Antígeno Sialil Lewis X/genética , Antígeno Sialil Lewis X/imunologia , Transdução de Sinais , Pele/imunologia , Pele/parasitologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/parasitologia
12.
Parasit Vectors ; 13(1): 24, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931865

RESUMO

BACKGROUND: Leishmaniasis, considered by the World Health Organization as one of the most important tropical diseases, is endemic in the Mediterranean Basin. The aim of this study was to evaluate epidemiological and clinical characteristics of cutaneous (CL) and mucocutaneous leishmaniasis (MCL) in La Fe University Hospital, Valencia, Spain. The particular focus was on diagnosis techniques and clinical differences according to the immunological status of the patients. METHODS: An eleven-year retrospective observational study of CL and MCL episodes at the hospital was performed. Epidemiological, clinical and therapeutic variables of each case, together with the microbiological and anatomopathological diagnosis, were analyzed. RESULTS: A total of 42 patients were included, 30 of them were male and 28 were immunocompetent. Most of the cases (36/42) were diagnosed in the last 5 years (2013-2017). The incidence of CL and MCL increased from 3.6/100,000 (2006-2012) to 13.58/100,000 (2013-2017). The majority of the patients (37/42) exhibited CL, in 30 cases as single lesions (30/37). Ulcerative lesions were more common in immunosuppressed patients (13/14) than in immunocompetent patients (20/28), (P = 0.2302). The length of lesion presence before diagnosis was 7.36 ± 6.72 months in immunocompetent patients and 8.79 ± 6.9 months in immunosuppressed patients (P = 0.1863). Leishmania DNA detection (92.3%) was the most sensitive diagnostic technique followed by Giemsa stain (65%) and histopathological examination (53.8%). Twelve patients (12/42) had close contact with dogs or were living near to kennels, and 10 of them did not present underlying conditions. Intralesional glucantime (21/42) and liposomal amphotericin B (7/42) were the most common treatments administered in monotherapy. All patients evolved successfully and no relapse was reported. CONCLUSIONS: Some interesting clinical and epidemiological differences were found in our series between immunocompetent and immunosuppressed patients. Future studies can take these results further especially by studying patients with biological therapy. Skin biopsies combining NAAT with histological techniques are the most productive techniques for CL or MCL diagnosis.


Assuntos
Leishmania/efeitos dos fármacos , Leishmaniose Cutânea , Leishmaniose Mucocutânea , Administração Cutânea , Adolescente , Adulto , Idoso , Anfotericina B/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Hospedeiro Imunocomprometido , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Leishmaniose Mucocutânea/diagnóstico , Leishmaniose Mucocutânea/tratamento farmacológico , Leishmaniose Mucocutânea/imunologia , Leishmaniose Mucocutânea/patologia , Masculino , Antimoniato de Meglumina/administração & dosagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Espanha/epidemiologia , Adulto Jovem
13.
PLoS Negl Trop Dis ; 14(1): e0006596, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923234

RESUMO

An association between increased susceptibility to infectious diseases and obesity has been described as a result of impaired immunity in obese individuals. It is not clear whether a similar linkage can be drawn between obesity and parasitic diseases. To evaluate the effect of obesity in the immune response to cutaneous Leishmania major infection, we studied the ability of C57BL/6 mice fed a hypercaloric diet (HSB) to control leishmaniasis. Mice with diet-induced obesity presented thicker lesions with higher parasite burden and a more intense inflammatory infiltrate in the infected ear after infection with L. major. There was no difference between control and obese mice in IFN-gamma or IL-4 production by auricular draining lymph node cells, but obese mice produced higher levels of IgG1 and IL-17. Peritoneal macrophages from obese mice were less efficient to kill L. major when infected in vitro than macrophages from control mice. In vitro stimulation of macrophages with IL-17 decreased their capacity to kill the parasite. Moreover, macrophages from obese mice presented higher arginase activity. To confirm the role of IL-17 in the context of obesity and infection, we studied lesion development in obese IL-17R-/- mice infected with L. major and found no difference in skin lesions and the leukocyte accumulation in the draining lymph node is redcuced in knockout mice compared between obese and lean animals. Our results indicate that diet-induced obesity impairs resistance to L. major in C57BL/6 mice and that IL-17 is involved in lesion development.


Assuntos
Leishmania major/patogenicidade , Leishmaniose Cutânea/imunologia , Obesidade , Animais , Dieta/efeitos adversos , Orelha/parasitologia , Feminino , Interferon gama , Interleucina-17 , Leishmaniose Cutânea/parasitologia , Linfonodos/citologia , Macrófagos Peritoneais/parasitologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Risco
14.
Parasite Immunol ; 42(2): e12688, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31797390

RESUMO

Leishmania major causes mild-to-severe cutaneous lesions resulting in significant disfigurations, if untreated. The drugs are toxic, and drug-resistance parasites are emerging. Therefore, a prophylactic vaccination is an urgent need. As no vaccine is available, we compared the genes expressed by virulent and avirulent parasites. We identify L major adenylate kinase (AdeK) as a probable vaccine candidate after a series of experimentations. We cloned the gene in mammalian pcDNA6/HisA and pet28a+ vector for in vivo expression following immunization and in vitro protein expression for booster, respectively. We observed that immunization of susceptible BALB/c mice with AdeK resulted in significant protection against L major challenge infection. The protection was accompanied by increased IFN-γ producing lymphocytes and reduced IL-4, IL-17 and IL-10 secreting central and effector Th2, Th17 and Treg memory cells, respectively. These observations indicate L major AdeK as a potential vaccine candidate.


Assuntos
Adenilato Quinase/imunologia , Leishmania major/imunologia , Vacinas contra Leishmaniose/imunologia , Leishmaniose Cutânea/prevenção & controle , Proteínas de Protozoários/imunologia , Adenilato Quinase/administração & dosagem , Adenilato Quinase/genética , Animais , Suscetibilidade a Doenças , Feminino , Imunização Secundária , Memória Imunológica/imunologia , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-17/biossíntese , Interleucina-4/biossíntese , Leishmaniose Cutânea/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/administração & dosagem , Proteínas de Protozoários/genética , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Células Th2/imunologia , Vacinação
15.
Parasite Immunol ; 42(2): e12685, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31742717

RESUMO

In previous studies, carried out in humans, we showed that females are resistant to Leishmania mexicana infection. We also showed that 17ß-estradiol (E2) induces killing of parasites inside of murine macrophages. In this work, we compared, for the first time, L mexicana survival inside of male (male BMDM) and female (female BMDM) bone marrow-derived macrophages (BMDM) treated in vitro with E2 or dihydrotestosterone (DHT). We also compared their levels of nitric oxide (NO), interleukin (IL)-6, IL-10, IL-12p70 and tumour necrosis factor (TNF-α). We found that female BMDM are a lot less susceptible to infection as compared with male BMDM. 17ß-estradiol induced killing of most parasites inside of female BMDM. Dihydrotestosterone, on the other hand, induced some parasite killing inside of some infected male BMDM. Interleukin-6 levels were higher in female BMDM treated with either hormone. Neither TNF-α nor IL-10 levels showed significant differences compared with sham controls. Interestingly IL-12p70 was more abundantly produced by sham female BMDM as compared with sham male BMDM. Only female BMDM treated with E2 trigger a robust IL-12p70 production, but it was significantly reduced in male BMDM. This suggests IL-12p70 is an important factor in female-macrophage resistance to L mexicana parasites.


Assuntos
Estradiol/metabolismo , Interleucina-12/imunologia , Leishmania mexicana/fisiologia , Leishmaniose Cutânea/imunologia , Macrófagos/imunologia , Animais , Citocinas/análise , Di-Hidrotestosterona/administração & dosagem , Estradiol/administração & dosagem , Feminino , Humanos , Leishmaniose Cutânea/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Óxido Nítrico/análise , Fatores Sexuais
16.
J Infect Dis ; 221(6): 973-982, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31748808

RESUMO

BACKGROUND: Skin lesions from patients infected with Leishmania braziliensis has been associated with inflammation induced by cytotoxic CD8+ T cells. In addition, CD8+ T cell-mediated cytotoxicity has not been linked to parasite killing. Meanwhile, the cytotoxic role played by natural killer (NK) cells in cutaneous leishmaniasis (CL) remains poorly understood. METHODS: In this study, we observed higher frequencies of NK cells in the peripheral blood of CL patients compared with healthy subjects, and that NK cells expressed more interferon-γ, tumor necrosis factor (TNF), granzyme B, and perforin than CD8+ T cells. RESULTS: We also found that most of the cytotoxic activity in CL lesions was triggered by NK cells, and that the high levels of granzyme B produced in CL lesions was associated with larger lesion size. Furthermore, an in vitro blockade of granzyme B was observed to decrease TNF production. CONCCLUSIONS: Our data, taken together, suggest an important role by NK cells in inducing inflammation in CL, thereby contributing to disease immunopathology.


Assuntos
Regulação Enzimológica da Expressão Gênica/imunologia , Granzimas/metabolismo , Inflamação/metabolismo , Células Matadoras Naturais/enzimologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Linfócitos T CD4-Positivos , Estudos de Casos e Controles , Granzimas/genética , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Perforina/genética , Perforina/metabolismo , Linfócitos T Citotóxicos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
17.
Acta Parasitol ; 65(1): 27-35, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31571138

RESUMO

PURPOSE: Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs), and their capacity to activate the immune response has been widely used in immunotherapies against different diseases, predominantly cancer. However, they have not been so widely used in immunotherapies against infectious diseases. Leishmania mexicana is the causative agent of cutaneous leishmaniasis in Mexico, which can result in localized cutaneous leishmaniasis (LCL) and diffuse cutaneous leishmaniasis (DCL). DCL is characterized by the incapability of the immune response to control the parasite, which thus disseminates to all teguments. Treatments against DCL have shown low efficacy, which is a reason why alternative therapies such as immunotherapies are promising. One adjuvant that has proven its effectiveness in immunotherapies against some cancers and infections is GK1, a component of the SPVac vaccine against porcine cysticercosis. GK1 has the capacity to elicit proinflammatory cytokines and chemokines from DCs and macrophages. METHODS: We pulsed bone marrow-derived dendritic cells (BMDCs) with GK1 and a lysate obtained from L. mexicana promastigotes and tested the efficacy of this combination against the infection of susceptible mice with L. mexicana. RESULTS: We found that BMDCs stimulated with GK1 and a lysate of L. mexicana promastigotes secreted IFN-γ and IL-12, and when they were adoptively transferred to BALB/c mice which were then infected with L. mexicana promastigotes, there was a reduction in the size of the lesion and in the parasite load. CONCLUSIONS: The adjuvant properties of GK1 along with parasite antigens may have a protective effect against the infection of BALB/c mice with L. mexicana.


Assuntos
Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Peptídeos Cíclicos/imunologia , Peptídeos Cíclicos/farmacologia , Proteínas de Protozoários/imunologia , Adjuvantes Imunológicos/farmacologia , Transferência Adotiva , Animais , Interferon gama/imunologia , Interleucina-12/imunologia , Leishmania mexicana , Leishmaniose Cutânea/imunologia , Leishmaniose Tegumentar Difusa/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Proteínas de Protozoários/farmacologia
19.
Front Immunol ; 10: 2697, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824492

RESUMO

In cutaneous Leishmaniasis the parasitic control in human host macrophages is still poorly understood. We found an increased expression of the human cathelicidin CAMP in skin lesions of Ethiopian patients with cutaneous leishmaniasis. Vitamin D driven, Cathelicidin-type antimicrobial peptides (CAMP) play an important role in the elimination of invading microorganisms. Recombinant cathelicidin was able to induce cell-death characteristics in Leishmania in a dose dependent manner. Using human primary macrophages, we demonstrated pro-inflammatory macrophages (hMDM1) to express a higher level of human cathelicidin, both on gene and protein level, compared to anti-inflammatory macrophages (hMDM2). Activating the CAMP pathway using Vitamin D in hMDM1 resulted in a cathelicidin-mediated-Leishmania restriction. Finally, a reduction of cathelicidin in hMDM1, using a RNA interference (RNAi) approach, increased Leishmania parasite survival. In all, these data show the human cathelicidin to contribute to the innate immune response against Leishmaniasis in a human primary cell model.


Assuntos
Peptídeos Catiônicos Antimicrobianos/imunologia , Imunidade Inata/imunologia , Leishmaniose Cutânea/imunologia , Macrófagos/imunologia , Células Cultivadas , Humanos
20.
J Immunol Res ; 2019: 2603730, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871953

RESUMO

This review is aimed at providing a comprehensive outline of the immune response displayed against cutaneous leishmaniasis (CL), the more common zoonotic infection caused by protozoan parasites of the genus Leishmania. Although of polymorphic clinical presentation, classically CL is characterized by leishmaniotic lesions on the face and extremities of the patients, which can be ulcerative, and even after healing can lead to permanent injuries and disfigurement, affecting significantly their psychological, social, and economic well-being. According a report released by the World Health Organization, the disability-adjusted life years (DALYs) lost due to leishmaniasis are close to 2.4 million, annually there are 1.0-1.5 million new cases of CL, and a numerous population is at risk in the endemic areas. Despite its increasing worldwide incidence, it is one of the so-called neglected tropical diseases. Furthermore, this review provides an overview of the existing knowledge of the host innate and acquired immune response to cutaneous species of Leishmania. The use of animal models and of in vitro studies has improved the understanding of parasite-host interplay and the complexity of immune mechanisms involved. The importance of diagnosis accuracy associated with effective patient management in CL reduction is highlighted. However, the multiple factors involved in CL epizoology associated with the unavailability of vaccines or drugs to prevent infection make difficult to formulate an effective strategy for CL control.


Assuntos
Interações Hospedeiro-Patógeno/imunologia , Leishmania/imunologia , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Gerenciamento Clínico , Suscetibilidade a Doenças/imunologia , Geografia Médica , Saúde Global , Humanos , Imunidade , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Avaliação de Resultados da Assistência ao Paciente , Índice de Gravidade de Doença
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