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1.
Trop Med Int Health ; 27(12): 1059-1064, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36329624

RESUMO

OBJECTIVE: Mycetoma is a neglected tropical disease caused by more than 70 different microorganisms and identified by the WHO as one of the high-priority diseases for developing diagnostic tests. To ensure the production of diagnostic assays for use by clinical staff in endemic regions, target product profiles (TPPs) were designed. METHODS: We describe the development of two TPPs: one for a diagnostic test able to identify the causative agent of mycetoma and another that would determine when treatment could be stopped. The TPPs were developed by considering product use, design, performance, product configuration and costs. RESULTS: Version 1.0 TPPs for two uses were posted by WHO for a 1-month online public consultation on 25 October 2021, and the final TPP was posted online on 5 May 2022. CONCLUSION: A major difficulty encountered in developing both TPPs was the large number of agents able to cause mycetoma and the lack of specific biomarkers for most of them.


Assuntos
Micetoma , Humanos , Micetoma/diagnóstico , Micetoma/tratamento farmacológico , Doenças Negligenciadas/diagnóstico , Bioensaio , Custos e Análise de Custo , Encaminhamento e Consulta
2.
Mod Rheumatol ; 32(2): 330-337, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33853472

RESUMO

OBJECTIVES: We aimed to determine the prevalence of anti-carbamylated protein (anti-CarP) antibodies in Mexican Hispanics with established rheumatoid arthritis (RA) and to assess their relationship with disease activity. METHODS: A cohort study was conducted in 278 patients with established RA during an 18-month follow-up. We measured IgG/IgM/IgA rheumatoid factor (RF), IgG anticitrullinated protein antibodies (ACPA) and IgG/IgM/IgA anti-CarP antibodies using enzyme-linked immunosorbent assay (ELISA). For disease activity, we performed the 28-joint disease activity score with erythrocyte sedimentation rate (DAS28-ESR). Repeated measures one-way ANOVA was used to test the association between anti-CarP IgG antibody status and longitudinal DAS28-ESR scores. Patients were evaluated at baseline and at 6, 12, and 18 months during follow-up. RESULTS: Anti-CarP IgG antibodies were positive in 47.8% of patients and, accounting for all isotypes, in 9.5% of patients with negative RF and ACPA. Triple antibody positivity was present in 42.6% of patients in our sample. Anti-CarP IgG antibody positivity did not show statistically significant differences in mean DAS28-ESR when compared to anti-CarP IgG antibody negative patients at baseline, 6, 12 or 18 months. CONCLUSION: Anti-CarP IgG antibodies are not associated to a higher disease activity in Hispanic patients with established RA. Our findings suggest that the clinical value of measuring anti-CarP antibodies in RA diminishes over time.


Assuntos
Artrite Reumatoide , Autoanticorpos , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Hispânico ou Latino , Humanos , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , Peptídeos Cíclicos , Fator Reumatoide
3.
Cytokine ; 138: 155400, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33338918

RESUMO

Influenza B virus (IBV) causes respiratory infectious disease. Cytokines are important immune mediators during infectious diseases. Cortisol and stress have been related to respiratory infection susceptibility and cytokine regulation. Little is known about systemic cytokines, cortisol, and perceived stress in the early stages of IBV infection. We researched the systemic cytokines and cortisol, as well as the perceived stress and blood cell count in patients infected with IBV. The diagnosis was established using the Luminex xTAG RVP kit and confirmed with qRT-PCR for IBV viral load. The perceived stress was evaluated using the perceived stress scale (PSS-10). Twenty-five plasma cytokines were determined using multiplex immunoassay and cortisol by ELISA. The leukocyte differential count was measured with a standard laboratory protocol. Th1, Th17, and IL-10 cytokines were higher in IBV infected patients (P < 0.05). Leukocytes and neutrophil count negatively correlated with viral load (P < 0.05). Perceived stress had a negative effect on monocyte and systemic cytokines in IBV infected patients (P < 0.05). Cortisol was higher in patients infected with IBV and correlated positively with CCL20 (P < 0.05). Cortisol showed a positive effect on most of the systemic cytokines (P < 0.05). In conclusion, a cytokine pattern was found in IBV infected patients, as well as the possible role of leukocyte counts in the control of IBV. Our results suggest the importance of cortisol and perceived stress on systemic cytokines in patients infected with IBV, but more studies are needed to understand their role in cytokine production in respiratory infectious disease.


Assuntos
Citocinas/sangue , Hidrocortisona/sangue , Influenza Humana/sangue , Percepção , Estresse Psicológico , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Vírus da Influenza B/metabolismo , Leucócitos/citologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Carga Viral
5.
Mycopathologia ; 183(4): 709-716, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29736739

RESUMO

Coccidioidomycosis is a fungal disease caused by Coccidioides immitis or Coccidioides posadasii. These fungi are endemic in the southern USA and northern Mexico. Immunocompromised patients are susceptible to develop severe forms of this fungal infection. Cytokines play an important role in controlling the fungal infection, but little is known about the predominant immunological environment in human lung tissue from fatal cases. Our aim was to analyze the pro-inflammatory and anti-inflammatory cytokines and monocyte/macrophages markers (CD14 and CD206) in the granulomas of six fatal cases of coccidioidomycosis. Cytokines and surface markers were higher in coccidioidomycosis cases when compared to control (P < 0.05). CD14 positive cells were increased inside the coccidioidal granuloma when compared to the outside (P < 0.05). No differences were found in the number of CD206+ cells inside the granuloma when compared to the outer population (P > 0.05). Interestingly, an analysis of stain intensity signals showed an increased signaling of CD14, CD206, IL-10 and TNFα inside the granuloma when compared to the outside (P < 0.05). iNOS and IL-12 gene expression were not detected in coccidioidomycosis cases, while IL-10, IL-6 and TGFß gene expression were detected, but the differences when compared to healthy lungs were not significant (P > 0.05). TNFα gene expression was lower in coccidioidomycosis cases when compared to healthy lung (P = 0.05). In conclusion, pro- and anti-inflammatory responses co-exist inside of the granulomas of fatal cases of coccidioidomycosis and the absent of iNOS and IL-12 gene expression may be related with patient's outcome.


Assuntos
Coccidioidomicose/parasitologia , Granuloma/patologia , Pulmão/patologia , Idoso , Citocinas/análise , Histocitoquímica , Humanos , Lectinas Tipo C/análise , Receptores de Lipopolissacarídeos/análise , Receptor de Manose , Lectinas de Ligação a Manose/análise , México , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo II/análise , Receptores de Superfície Celular/análise , Estudos Retrospectivos , Estados Unidos
6.
Mediators Inflamm ; 2014: 921054, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25614715

RESUMO

In 2009, a new influenza A (H1N1) virus affected many persons around the world. There is an urgent need for finding biomarkers to distinguish between influenza A (H1N1)pdm09 and seasonal influenza virus. We investigated these possible biomarkers in the lung of fatal cases of confirmed influenza A (H1N1)pdm09. Cytokines (inflammatory and anti-inflammatory) and cellular markers (macrophages and lymphocytes subpopulation markers) were analyzed in lung tissue from both influenza A (H1N1)pdm09 and seasonal influenza virus. High levels of IL-17, IFN-γ, and TNF-α positive cells were identical in lung tissue from the influenza A (H1N1)pdm09 and seasonal cases when compared with healthy lung tissue (P < 0.05). Increased IL-4+ cells, and CD4+ and CD14+ cells were also found in high levels in both influenza A (H1N1)pdm09 and seasonal influenza virus (P < 0.05). Low levels of CD206+ cells (marker of alternatively activated macrophages marker in lung) were found in influenza A (H1N1)pdm09 when compared with seasonal influenza virus (P < 0.05), and the ratio of CD206/CD14+ cells was 2.5-fold higher in seasonal and noninfluenza group compared with influenza A (H1N1)pdm09 (P < 0.05). In conclusion, CD206+ cells differentiate between influenza A (H1N1)pdm09 and seasonal influenza virus in lung tissue of fatal cases.


Assuntos
Vírus da Influenza A Subtipo H1N1/classificação , Influenza Humana/imunologia , Influenza Humana/virologia , Lectinas Tipo C/metabolismo , Macrófagos/citologia , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Antígenos CD4/metabolismo , Feminino , Humanos , Inflamação , Influenza Humana/mortalidade , Receptores de Lipopolissacarídeos/metabolismo , Pulmão/metabolismo , Masculino , Receptor de Manose , Estudos Retrospectivos , Adulto Jovem
7.
Infect Immun ; 80(10): 3587-601, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22851755

RESUMO

Nocardia brasiliensis is a Gram-positive facultative intracellular bacterium frequently isolated from human actinomycetoma. However, the pathogenesis of this infection remains unknown. Here, we used a model of bacterial delipidation with benzine to investigate the role of N. brasiliensis cell wall-associated lipids in experimental actinomycetoma. Delipidation of N. brasiliensis with benzine resulted in complete abolition of actinomycetoma without affecting bacterial viability. Chemical analyses revealed that trehalose dimycolate and an unidentified hydrophobic compound were the principal compounds extracted from N. brasiliensis with benzine. By electron microscopy, the extracted lipids were found to be located in the outermost membrane layer of the N. brasiliensis cell wall. They also appeared to confer acid-fastness. In vitro, the extractable lipids from the N. brasiliensis cell wall induced the production of the proinflammatory cytokines interleukin-1ß (IL-1ß), IL-6, and CCL-2 in macrophages. The N. brasiliensis cell wall extractable lipids inhibited important macrophage microbicidal effects, such as tumor necrosis factor alpha (TNF-α) and nitric oxide (NO) production, phagocytosis, bacterial killing, and major histocompatibility complex class II (MHC-II) expression in response to gamma interferon (IFN-γ). In dendritic cells (DCs), N. brasiliensis cell wall-associated extractable lipids suppressed MHC-II, CD80, and CD40 expression while inducing tumor growth factor ß (TGF-ß) production. Immunization with delipidated N. brasiliensis induced partial protection preventing actinomycetoma. These findings suggest that N. brasiliensis cell wall-associated lipids are important for actinomycetoma development by inducing inflammation and modulating the responses of macrophages and DCs to N. brasiliensis.


Assuntos
Células Dendríticas/efeitos dos fármacos , Lipídeos/farmacologia , Macrófagos/efeitos dos fármacos , Micetoma/microbiologia , Nocardiose/microbiologia , Nocardia/metabolismo , Alcanos , Animais , Linhagem Celular , Parede Celular/química , Parede Celular/metabolismo , Células Dendríticas/metabolismo , Interferon gama/farmacologia , Lipídeos/química , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Micetoma/imunologia , Nocardia/classificação , Nocardia/ultraestrutura , Nocardiose/imunologia , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo
8.
Infect Immun ; 80(7): 2493-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22547544

RESUMO

Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P < 0.05) in footpad tissue and spleen. Treg subpopulations peaked at days 7 and 15 (P < 0.01) in the footpad and spleen, respectively. Transforming growth factor ß1 (TGF-ß1) and interleuki-10 (IL-10) are cytokines known for their immunosuppressive effects. During early and chronic infections, these cytokines were elevated with increased TGF-ß1 levels from days 3 to 30 (P < 0.01) and sustained IL-10 expression throughout infection compared to uninfected mice. IL-6 production was increased at day 3 (P < 0.01), whereas gamma interferon (IFN-γ), IL-17A, and IL-23 levels were highest at day 15 postinfection (P < 0.01) when a decrease in the bacterial load (>1 log) was also observed (P < 0.05). After these changes, at 30 to 60 days postinfection, IFN-γ production was decreased, whereas the expression of anti-inflammatory cytokines and the bacterial load again increased (P < 0.05). The increment in Treg cells and the related cytokine profile correlated with reduced inflammation at day 15 (P < 0.05) in the footpad. We conclude that N. brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection.


Assuntos
Evasão da Resposta Imune , Nocardiose/imunologia , Nocardiose/microbiologia , Nocardia/patogenicidade , Animais , Carga Bacteriana , Doença Crônica , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Tolerância Imunológica , Camundongos , Camundongos Endogâmicos BALB C , Viabilidade Microbiana , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Fatores de Tempo
9.
BMC Infect Dis ; 12: 15, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22264245

RESUMO

BACKGROUND: Community-acquired pneumonia (CAP) is considered the most important cause of death from infectious disease in developed countries. Severity assessment scores partially address the difficulties in identifying high-risk patients. A lack of specific and valid pathophysiologic severity markers affect early and effective sepsis therapy. HMGB-1, sRAGE and RAGE have been involved in sepsis and their potential as severity markers has been proposed. The aim of this study was to evaluate HMGB-1, RAGE and sRAGE levels in patients with CAP-associated sepsis and determine their possible association with clinical outcome. METHOD: We evaluated 33 patients with CAP-associated sepsis admitted to the emergency room and followed in the medical wards. Severity assessment scores (CURB-65, PSI, APACHE II, SOFA) and serologic markers (HMGB-1, RAGE, sRAGE) were evaluated on admission. RESULTS: Thirty patients with a diagnosis of CAP-associated sepsis were enrolled in the study within 24 hours after admission. Fourteen (46.6%) had pandemic (H1N1) influenza A virus, 2 (6.6%) had seasonal influenza A and 14 other diagnoses. Of the patients in the study group, 16 (53.3%) had a fatal outcome. ARDS was observed in 17 (56.6%) and a total of 22 patients had severe sepsis on admission (73%). The SOFA score showed the greatest difference between surviving and non-surviving groups (P = .003) with similar results in ARDS patients (P = .005). sRAGE levels tended to be higher in non-surviving (P = .058) and ARDS patients (P = .058). Logistic regression modeling demonstrated that SOFA (P = .013) and sRAGE (P = .05) were the only variables that modified the probability of a fatal outcome. CONCLUSION: The association of elevated sRAGE with a fatal outcome suggests that it may have an independent causal effect in CAP. SOFA scores were the only clinical factor with the ability to identify surviving and ARDS patients.


Assuntos
Biomarcadores/sangue , Infecções Comunitárias Adquiridas/patologia , Pneumonia Bacteriana/complicações , Pneumonia Bacteriana/patologia , Receptor para Produtos Finais de Glicação Avançada/sangue , Sepse/patologia , Índice de Gravidade de Doença , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/mortalidade , Feminino , Humanos , Vírus da Influenza A , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/mortalidade , Prognóstico , Sepse/diagnóstico , Sepse/mortalidade
10.
Immunopharmacol Immunotoxicol ; 34(3): 477-83, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22564175

RESUMO

Diethylcarbamazine (DEC) is an anthelmintic piperazine derivative drug with putative immunomodulating properties, including increased platelet and granulocyte adhesion to parasites and enhanced production of cytokines. To further analyse these properties in a well-established animal model, we evaluated the effect of DEC on antibody, cellular cytokine response and respiratory burst in BALB/c mice. Animals were challenged with a thymus-dependent (tetanus toxoid, (TT)) and with a thymus-independent (lipopolysaccharide, (LPS)) antigen and treated with DEC for seven days with two different doses (50 mg/day and 500 mg/day). Serum was assessed for antibody production at 0, 4, 7, 14, 21 and 28 days after stimulation and at 0, 24 and 48 h for IL-2, IFN-γ, IL-10 and IL-12 release. Respiratory burst of neutrophils and monocytes from peripheral blood was measured by flow cytometry. We found low-dose treatment with DEC enhanced cytokine production vs. TT and antibody production vs. LPS, whereas a higher dose enhanced significantly the respiratory burst of both polymorphonuclear leukocytes and monocytes, with a significant higher effect on the former. Our results suggest a stimulating, dose-dependent immunomodulatory effect of DEC with a higher effect on the phagocytic cells.


Assuntos
Citocinas/imunologia , Dietilcarbamazina/farmacologia , Imunidade Humoral/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Explosão Respiratória/efeitos dos fármacos , Animais , Feminino , Imunidade Humoral/imunologia , Lipopolissacarídeos/farmacologia , Inibidores de Lipoxigenase/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/imunologia , Neutrófilos/imunologia , Explosão Respiratória/imunologia , Toxoide Tetânico/farmacologia
11.
Arch Med Res ; 53(2): 170-178, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34702588

RESUMO

BACKGROUND: Septic arthritis (SA) is a medical emergency. The most common etiological agents are bacteria, which activate the local immune response coordinated by cytokines; however, little is known about the cytokine profile in human SA. AIM: To determine the association of local and systemic cytokine profiles with the severity and prognosis of patients with SA. METHODS: Patients with clinical and laboratory diagnosed SA were enrolled as well as a control group. Serum and synovial fluid (SF) samples were obtained for determining cytokines and glucose levels; SF samples were used for histological analysis. Osteochondral damage and general health status and quality of life (SF-36) were evaluated during recruitment day. WOMAC osteoarthritis index score and SF-36 questionnaire were used a year after recruitment day as a follow up. RESULTS: A systemic and local proinflammatory cytokine profile was found in patients compared to the control group (p <0.05). IL-6 was 28 and 525 times higher than controls in sera and SF, respectively (p <0.0001). Systemic IL-6 correlated negatively with general mental health score (p = 0.0184) and was associated with a higher osteoarthritis index after one year follow-up in the patients (p = 0.0352). HMGB1 in SF was found higher in patients with SA (p <0.0001), and it was associated with osteochondral damage (p = 0.0042). TNF-α in SF correlated negatively with SF-36 questionnaire one year after patients' recruitment in role limitation score (p = 0.0318), body pain score (p = 0.0315), and general mental health score (p = 0.0197). CONCLUSION: Serum and SF cytokine signatures are associated with disease severity and prognosis in patients with SA.


Assuntos
Artrite Infecciosa , Citocinas , Artrite Infecciosa/diagnóstico , Humanos , Prognóstico , Qualidade de Vida , Líquido Sinovial/química
12.
Cir Cir ; 90(3): 319-331, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35636950

RESUMO

OBJECTIVE: The objective of the study was to determine the added value of synovial fluid (SF) glucose levels and other biochemical parameters as possible biomarkers of bacterial septic arthritis (SA). MATERIALS AND METHODS: We prospectively examined adult patients with SA. As a control group, adults with uninfected joints were enrolled. SF samples were obtained, and microbiological analyses were made. SF glucose levels, pH, and leukocyte esterase were measured using a glucometer and colorimetric test strips. Blood samples were collected from both groups to determine glucose levels. RESULTS: We included eight subjects with knee ligaments lesions, six with meniscus lesions, and five with osteoarthritis as the control group, as well as 20 patients with SA. SF culture was positive in 60%. SF glucose levels from patients were lower than the controls (p = 0.0018) with the lowest concentration in patients with a positive culture (p = 0.0004). Blood and SF glucose concentration from the positive culture patients were compared (p < 0.0001). Leukocyte esterase presented the highest values in patients with a positive culture (p < 0.0001) and a more acidic pH was found compared to the control group (p < 0.0001). CONCLUSION: These biochemical parameters might be a quick and inexpensive added value for distinguishing between infective and non-infective joint disease.


OBJETIVO: Evaluar el valor añadido de los niveles de glucosa en el líquido sinovial (LS) y otros parámetros bioquímicos en el diagnostico de artritis séptica (AS). MATERIAL Y MÉTODOS: Análisis prospectivo de pacientes adultos con AS. Pacientes con articulaciones no infectadas fueron incluidos como grupo control. Se tomaron muestras de LS y sangre para la realización de análisis microbiológicos y bioquímicos en los pacientes y controles. RESULTADOS: Incluimos 8 sujetos con lesión ligamentosa de rodilla, 6 con lesiones meniscales y 5 con osteoartritis como grupo control, así como 20 pacientes con AS. El cultivo de LS fue positivo en 60%. Los niveles de glucosa en LS de pacientes con AS fueron más bajos que los controles (P = 0.0018) con la concentración más baja en pacientes con cultivo positivo (p = 0.0004). La relación de glucosa en sangre y LS de pacientes con cultivo positivo se vio afectada (p < 0.0001). La esterasa leucocitaria presentó valores más altos en pacientes con cultivo positivo (p < 0.0001); se encontró un pH más ácido en comparación con el grupo control (p < 0.0001). CONCLUSIÓN: Estos parámetros bioquímicos podrían ser un valor agregado útil, rápido y económico para distinguir entre enfermedad articular infecciosa y no infecciosa.


Assuntos
Artrite Infecciosa , Glucose , Adulto , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/microbiologia , Biomarcadores/análise , Hidrolases de Éster Carboxílico/análise , Glucose/análise , Humanos
13.
Plasmid ; 65(1): 25-31, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20875450

RESUMO

Nocardia brasiliensis, is a bacteria that lives as saprophyte in soil and causes a disease called actinomycetoma in both human and animals. Nocardia brasiliensis is an intracellular, facultative bacterium that replicates and survives within host macrophages. The mechanisms involved in the evasion of the microbicidal actions of macrophages remain unclear. The filamentous growth of N. brasiliensis is resistant to unicellular preparations, leading to inaccurate quantification of bacterial numbers by means of colony forming units (CFU). As successful survival studies with green fluorescent protein (GFP)-expressing bacterial strains have been reported, we constructed a recombinant GFP-expressing strain of N. brasiliensis. The virulence of the modified strain is maintained because it induces mycetoma in BALB/c mice. This new strain can be used for bacterial survival assays using cytometry and to elucidate the pathogenicity mechanisms in Actinomycetoma infection.


Assuntos
Técnicas Genéticas , Proteínas de Fluorescência Verde/metabolismo , Micetoma/microbiologia , Nocardia/genética , Nocardia/patogenicidade , Plasmídeos/genética , Animais , Bioensaio , Contagem de Colônia Microbiana , Citometria de Fluxo , Fluorescência , Humanos , Macrófagos/citologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Nocardia/crescimento & desenvolvimento , Nocardiose/microbiologia , Transformação Genética , Virulência/genética
14.
Acta Trop ; 222: 106041, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34252383

RESUMO

Cutaneous leishmaniasis is the most common form of leishmaniasis in humans. The disease is caused by several species, such as Leishmania mexicana, a protozoa parasite. Several major risk factors are associated with this disease, including poverty, poor housing, inadequate domestic hygiene, malnutrition, mobility, and occupational exposure. Solar radiation (UVB) has not been considered a risk factor because there is no scientific evidence demonstrating a correlation with increased susceptibility to cutaneous leishmaniasis. In this study, the shaved skin of the back of C57BL/6 mice was irradiated with 24.2 mJ/cm2 of UVB. A delayed-type hypersensitivity (DTH) reaction was used to assess UV-induced immune suppression. Skin lesions were quantitated, and parasite burden and the presence of anti-Leishmania mexicana antibodies in serum and germinal centers in draining lymph nodes were determined. We found an increased in the lesion size and parasitic load in UVB-irradiated mice compared to the WT mice and B lymphocyte activation in draining lymph nodes and increased IgG1 production. Our results show an important role of UVB-induced suppression in cutaneous leishmaniasis through local production of IL-10 and systemic IgG1antibodies. This is the first study that demonstrates the effects of UVB radiation on cutaneous leishmaniasis by Leishmania mexicana.


Assuntos
Terapia de Imunossupressão , Leishmaniose Cutânea , Pele/efeitos da radiação , Raios Ultravioleta , Animais , Leishmania mexicana , Leishmaniose Cutânea/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pele/parasitologia
15.
Viral Immunol ; 34(8): 573-578, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34415814

RESUMO

Eosinophils participate in the immune response against many pathogens, including viruses. Since mouse eosinophils are susceptible to influenza A virus infection and possess antiviral activity, we evaluated the expression of sialic acid residues in human eosinophils and their response against influenza virus in vitro. We demonstrated that human eosinophils express α2,6- and α2,3-linked sialic acid, and drastically reduced influenza virus titer. After influenza virus exposure, eosinophils upregulated retinoic acid-inducible gene I (RIG-I) mRNA expression, but no other pattern recognition receptors. Finally, high concentrations of interleukin-8 (IL-8) were found in influenza virus-exposed eosinophil cultures. These data suggest that human eosinophils possess antiviral activity and may play a role in the innate immune response to influenza virus.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Eosinófilos , Humanos , Interleucina-8 , Receptores do Ácido Retinoico
16.
FEMS Microbiol Lett ; 368(8)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33956121

RESUMO

Mycetoma is a chronic human infectious disease that produces severe deformation frequently in the lower extremities. Etiological agents include fungi (eumycetoma) and bacteria (actinomycetoma) that produce similar clinical and microscopic changes. The clinical appearance includes swelling, abscesses, ulcers, scars and sinuses that drain purulent material with microbe microcolonies. The pathogenesis of actinomycetoma has been studied mainly in rodents. Using this approach, it was found that Nocardia brasiliensis produces proteases that may play a role in tissue damage, as well as immunosuppressive molecules, such as brasilicardin A. Nitric oxide (NO) is a molecule with biological activities depending on its local concentration. Its effect on killing intracellular bacteria such as Mycobacterium tuberculosis has been known for decades. NO plays an important role in innate and adaptive immunity. It can promote or suppress some biological activities despite its short half-ife. NO is produced by three different nitric oxide synthases (NOS). We used the genetic blockade of eNOS in C57BL/6 mice to demonstrate the role of NO in actinomycetoma development. Inflammation and actinomycetoma were prevented in genetically modified mice infected with N. brasiliensis. T cell proliferation was increased in these rodents, and antibody production, IL-6 and IL-10 expression were similar and TNF-α was lower.


Assuntos
Micetoma/imunologia , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico/imunologia , Nocardia , Animais , Citocinas/imunologia , Feminino , Ativação Linfocitária , Camundongos Endogâmicos C57BL , Camundongos Knockout , Micetoma/microbiologia , Linfócitos T/imunologia
17.
Pathog Dis ; 78(8)2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33016312

RESUMO

Leishmaniosis is currently considered a serious public health problem and it is listed as a neglected tropical disease by World Health Organization (WHO). Despite the efforts of the scientific community, it has not been possible to develop an effective vaccine. Current treatment consists of antimonials that is expensive and can cause adverse effects. It is essential to fully understand the immunopathogenesis of the disease to develop new strategies to prevent, treat and eradicate the disease. Studies on animal models have shown a new paradigm in the resolution or establishment of infection by Leishmania mexicana where a wide range of cytokines, antibodies and cells are involved. In recent years, the possibility of a new therapy with monoclonal antibodies has been considered, where isotype, specificity and concentration are critical for effective therapy. Would be better to create/generate a vaccine to induce host protection or produce passive immunization with engineering monoclonal antibodies to a defined antigen? This review provides an overview that includes the current known information on the immune response that are involved in the complex host-parasite relationship infection caused by L. mexicana.


Assuntos
Imunidade Adaptativa , Interações Hospedeiro-Parasita , Imunidade Inata , Leishmaniose Cutânea/imunologia , Animais , Anticorpos Antiprotozoários , Modelos Animais de Doenças , Humanos , Imunidade , Leishmania mexicana/imunologia , Camundongos
18.
PLoS Negl Trop Dis ; 14(10): e0008775, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33091049

RESUMO

Mycetoma is a chronic infectious disease that can be caused by fungi or bacteria, Madurella mycetomatis and Nocardia brasiliensis are frequent etiologic agents of this disease. Mycetoma produced by bacteria is known as actinomycetoma. In mycetoma produced by fungi (eumycetoma) and actinomycetoma, diagnosis of the disease is based on clinical findings: severe inflammation, with deformities of affected tissues, abscesses, fistulae, sinuses and discharge of purulent material that contains micro colonies of the etiologic agent. Microscopic examination of infected tissue is similar regardless of the offending microbe; hallmark of infected tissue is severe inflammation with abundant neutrophils around micro colonies and granuloma formation with macrophages, lymphocytes, dendritic and foamy cells. Even though medical treatment is available for mycetoma patients, amputation, or surgical intervention is frequently needed. The pathogenesis of actinomycetoma is little known, most information was obtained from experimental animal models infected with bacteria. In other experimental mice infections with different microbes, it was demonstrated that nitric oxide is responsible for the intracellular killing of Mycobacterium tuberculosis by activated macrophages. Nitric oxide is a free radical with potent stimulatory and suppressive effects in innate and adaptive immunity. The unstable nitric oxide molecule is produced by action of nitric oxide synthases on L-arginine. There are three nitric oxide synthases expressed in different cells and tissues, two are constitutively expressed one in neurons, and the other in endothelial cells and one that is inducible in macrophages. Aminoguanidine is a competitive inhibitor of inducible nitric oxide synthase. Its administration in experimental animals may favor or harm them. We used aminoguanidine in mice infected with Nocardia brasiliensis, and demonstrated that all treated animals were protected from actinomycetoma development. Anti N. brasiliensis antibodies and T cell proliferation were not affected, but inflammation was reduced.


Assuntos
Guanidinas/administração & dosagem , Micetoma/tratamento farmacológico , Micetoma/enzimologia , Óxido Nítrico Sintase Tipo II/imunologia , Animais , Progressão da Doença , Feminino , Humanos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Micetoma/imunologia , Micetoma/microbiologia , Neutrófilos/imunologia , Óxido Nítrico/imunologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/genética , Nocardia/efeitos dos fármacos , Nocardia/fisiologia
19.
Viral Immunol ; 32(5): 198-207, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31140942

RESUMO

Eosinophils have been mainly associated with parasitic infection and pathologies such as asthma. Some patients with asthma present a high number of eosinophils in their airways. Since respiratory viruses are associated with asthma exacerbations, several studies have evaluated the role of eosinophils against respiratory viruses. Eosinophils contain and produce molecules with antiviral activity, including RNases and reactive nitrogen species. They can also participate in adaptive immunity, serving as antigen-presenting cells. Eosinophil antiviral response has been demonstrated against some respiratory viruses in vitro and in vivo, including respiratory syncytial virus and influenza. Given the implication of respiratory viruses in asthma, the eosinophil antiviral role might be an important factor to consider in this pathology.


Assuntos
Eosinófilos/imunologia , Infecções Respiratórias/virologia , Viroses/imunologia , Imunidade Adaptativa , Animais , Asma/imunologia , Asma/virologia , Humanos , Camundongos , Orthomyxoviridae/imunologia , Infecções Respiratórias/imunologia , Vírus
20.
Arch Med Res ; 39(3): 306-11, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18279703

RESUMO

BACKGROUND: CD64 and CD206 receptors play an important role in the internalization of Mycobacterium tuberculosis into macrophages. RAGE, described in diabetes (a predisposing factor for tuberculosis), captures glycosylated proteins. METHODS: Four groups of 15 patients with type 2 diabetes mellitus (DM2), pulmonary tuberculosis (PTB), type 2 diabetes and pulmonary tuberculosis (DM2-PTB), and controls (CG) were studied. Blood was obtained and mononuclear cells (MNC) isolated and cultured to obtain adherent cells (AC) and then stimulated with M. tuberculosis H37Rv lipids. Expression of CD64, CD206 and RAGE was measured by flow cytometry. RESULTS: In the groups without stimulus, PTB and DM2-PTB expressed greater mean fluorescence intensity (MFI) of CD64 and CD206 compared to CG. DM2-PTB showed a decrease in expression compared to PTB. After lipid stimulation no significant difference between groups occurred. In AC without stimulus, RAGE expression was significantly greater in DM2, PTB and DM2-PTB. When DM2-PTB was compared to PTB, a significant decrease in expression occurred. After lipid stimulation, only DM2 cells showed greater MFI. CONCLUSIONS: Diabetes affects expression of the three receptors. PTB cells significantly increase them. Diabetes and tuberculosis infection decrease expression compared to PTB alone. Diabetes did not alter CD64 and CD206 expression in infected patients. RAGE expression increases in patients with PTB as well as in diabetics. This suggests that RAGE could also behave as a receptor for M. tuberculosis.


Assuntos
Complicações do Diabetes/metabolismo , Complicações do Diabetes/patologia , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/metabolismo , Mycobacterium tuberculosis/fisiologia , Receptores de Superfície Celular/metabolismo , Receptores de IgG/metabolismo , Receptores Imunológicos/metabolismo , Tuberculose/metabolismo , Tuberculose/patologia , Adulto , Adesão Celular , Feminino , Humanos , Masculino , Receptor de Manose , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada , Tuberculose/complicações
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