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1.
Eur J Med Res ; 27(1): 1, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34980252

RESUMO

BACKGROUND: Cryptococcal meningitis (CM) has a high morbidity and mortality due to the low detection of Cryptococcus in cerebrospinal fluid (CSF) during the early stage of the disease with traditional methods. CASE PRESENTATION: In addition to the traditional methods of India ink staining and cryptococcal antigen (CrAg), we used nanopore sequencing and next-generation sequencing (NGS) to detect pathogenic DNA in CSF samples of three patients with CM. The CSF samples of all three patients were positive by India ink staining and CrAg. NGS also detected Cryptococcus in all three CSF samples. Nanopore sequencing detected Cryptococcus in two CSF samples. CONCLUSION: Nanopore sequencing may be useful in assisting with the clinical diagnosis of CM. Further research is needed to determine the sensitivity and specificity of nanopore sequencing of CSF.


Assuntos
Cryptococcus/genética , Meningite Criptocócica/líquido cefalorraquidiano , Sequenciamento por Nanoporos/métodos , Adulto , Antígenos de Fungos/imunologia , Biomarcadores/líquido cefalorraquidiano , Cryptococcus/imunologia , Feminino , Humanos , Masculino , Meningite Criptocócica/diagnóstico , Pessoa de Meia-Idade
2.
Front Immunol ; 12: 749074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867977

RESUMO

In this study, the human immune response mechanisms against Sporothrix brasiliensis and Sporothrix schenckii, two causative agents of human and animal sporotrichosis, were investigated. The interaction of S. brasiliensis and S. schenckii with human monocyte-derived macrophages (hMDMs) was shown to be dependent on the thermolabile serum complement protein C3, which facilitated the phagocytosis of Sporothrix yeast cells through opsonization. The peptidorhamnomannan (PRM) component of the cell walls of these two Sporothrix yeasts was found to be one of their surfaces exposed pathogen-associated molecular pattern (PAMP), leading to activation of the complement system and deposition of C3b on the Sporothrix yeast surfaces. PRM also showed direct interaction with CD11b, the specific component of the complement receptor-3 (CR3). Furthermore, the blockade of CR3 specifically impacted the interleukin (IL)-1ß secretion by hMDM in response to both S. brasiliensis and S. schenckii, suggesting that the host complement system plays an essential role in the inflammatory immune response against these Sporothrix species. Nevertheless, the structural differences in the PRMs of the two Sporothrix species, as revealed by NMR, were related to the differences observed in the host complement activation pathways. Together, this work reports a new PAMP of the cell surface of pathogenic fungi playing a role through the activation of complement system and via CR3 receptor mediating an inflammatory response to Sporothrix species.


Assuntos
Antígenos de Fungos/imunologia , Proteínas do Sistema Complemento/imunologia , Glicoproteínas/imunologia , Macrófagos/imunologia , Sporothrix , Parede Celular/imunologia , Ativação do Complemento , Citocinas/imunologia , Humanos , L-Lactato Desidrogenase/imunologia , Antígeno de Macrófago 1/imunologia , Macrófagos/microbiologia , Moléculas com Motivos Associados a Patógenos/imunologia , Fagocitose
3.
Sci Rep ; 11(1): 23440, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34873233

RESUMO

Fungal infection is an important health problem in Latin America, and in Brazil in particular. Paracoccidioides (mainly P. brasiliensis and P. lutzii) is responsible for paracoccidioidomycosis, a disease that affects mainly the lungs. The glycoprotein gp43 is involved in fungi adhesion to epithelial cells, which makes this protein an interesting target of study. A specific stretch of 15 amino acids that spans the region 181-195 (named P10) of gp43 is an important epitope of gp43 that is being envisioned as a vaccine candidate. Here we show that synthetic P10 forms typical amyloid aggregates in solution in very short times, a property that could hamper vaccine development. Seeds obtained by fragmentation of P10 fibrils were able to induce the aggregation of P4, but not P23, two other peptides derived from gp43. In silico analysis revealed several regions within the P10 sequence that can form amyloid with steric zipper architecture. Besides, in-silico proteolysis studies with gp43 revealed that aggregation-prone, P10-like peptides could be generated by several proteases, which suggests that P10 could be formed under physiological conditions. Considering our data in the context of a potential vaccine development, we redesigned the sequence of P10, maintaining the antigenic region (HTLAIR), but drastically reducing its aggregation propensity.


Assuntos
Amiloide/química , Antígenos de Neoplasias/química , Antígenos/química , Paracoccidioides/imunologia , Paracoccidioidomicose/prevenção & controle , Algoritmos , Animais , Antígenos de Fungos/imunologia , Dicroísmo Circular , Biologia Computacional/métodos , Simulação por Computador , Epitopos , Proteínas Fúngicas/química , Vacinas Fúngicas/imunologia , Glicoproteínas/química , Humanos , Técnicas In Vitro , Paracoccidioidomicose/imunologia , Peptídeos/química , Conformação Proteica , Dobramento de Proteína , Software , Solventes/química , Desenvolvimento de Vacinas
4.
Front Immunol ; 12: 725882, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737741

RESUMO

Monoclonal antibodies (mAbs) are promising alternatives to treat infectious diseases, especially given their potential for applications in combination therapies with antimicrobial drugs to enhance the antifungal efficacy. Protection mediated by mAbs used to treat experimental paracoccidioidomycosis (PCM) has been demonstrated previously. Our aim in the present work was to characterize a monoclonal antibody (mAbF1.4) raised against a cell wall glycoconjugate fraction of Paracoccidioides spp. and to analyze its efficacy combined with trimethoprim-sulfamethoxazole (TMP/SMX) as treatment for experimental PCM. We demonstrated that the epitope recognized by mAbF1.4 is consistent with branched glucose residues present on a cell wall ß-glucan polymer. In vitro, mAbF1.4 increased the phagocytic capacity and nitric oxide concentration induced by the macrophage cell line J774.1A, and this resulted in a significant reduction in the viability of the opsonophagocytized yeasts. In vivo, we detected a significant reduction in pulmonary fungal burdens of mice treated with mAbF1.4 in association with TMP/SMX, which correlated with increased pulmonary concentrations (determined by ELISA) of IFN- Î³, TNF-α, IL-10 and IL-17. In parallel, we observed a decrease in IL-4, suggesting that the treatment was associated with a mixed Th1-Th17 type immune response. Histopathology of lung segments from mice receiving the combination therapy showed a significant reduction in granulomas, which were well-defined, and improved maintenance of lung architecture. These findings demonstrate that mAbF1.4 + TMP/SMX therapy is a promising approach to combat PCM as well as decrease disease sequelae and highlights the potential benefits of immune mediators in PCM combined immunotherapy.


Assuntos
Anticorpos Monoclonais/farmacologia , Imunoterapia/métodos , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Animais , Antifúngicos/farmacologia , Antígenos de Fungos/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Paracoccidioidomicose/tratamento farmacológico , Paracoccidioidomicose/microbiologia
5.
Cells ; 10(11)2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34831237

RESUMO

During the current era of the COVID-19 pandemic, the dissemination of Mucorales has been reported globally, with elevated rates of infection in India, and because of the high rate of mortality and morbidity, designing an effective vaccine against mucormycosis is a major health priority, especially for immunocompromised patients. In the current study, we studied shared Mucorales proteins, which have been reported as virulence factors, and after analysis of several virulent proteins for their antigenicity and subcellular localization, we selected spore coat (CotH) and serine protease (SP) proteins as the targets of epitope mapping. The current study proposes a vaccine constructed based on top-ranking cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and B cell lymphocyte (BCL) epitopes from filtered proteins. In addition to the selected epitopes, ß-defensins adjuvant and PADRE peptide were included in the constructed vaccine to improve the stimulated immune response. Computational tools were used to estimate the physicochemical and immunological features of the proposed vaccine and validate its binding with TLR-2, where the output data of these assessments potentiate the probability of the constructed vaccine to stimulate a specific immune response against mucormycosis. Here, we demonstrate the approach of potential vaccine construction and assessment through computational tools, and to the best of our knowledge, this is the first study of a proposed vaccine against mucormycosis based on the immunoinformatics approach.


Assuntos
Vacinas Fúngicas/química , Vacinas Fúngicas/imunologia , Mucormicose/prevenção & controle , Rhizopus/imunologia , Adjuvantes Imunológicos , Antígenos de Fungos/imunologia , Biologia Computacional , Reações Cruzadas , Mapeamento de Epitopos , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Humanos , Modelos Moleculares , Mucorales/imunologia , Conformação Proteica , Receptor 2 Toll-Like/química , Vacinas de Subunidades/química , Vacinas de Subunidades/imunologia
6.
Front Immunol ; 12: 747730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804031

RESUMO

Background: Alternaria is a major source of asthma-inducing allergens. Allergen-specific immunotherapy improves the progression of allergic asthma. The current treatment is based on crude Alternaria extracts. Alt a 1 is the predominant allergen in Alternaria. However, the treatment efficacy of recombinant Alt a 1 (rAlt a 1) in an asthmatic animal model and its influence on Tfh and Breg cells are unknown. Objective: To explore the therapeutic treatment effects of rAlt a 1 on the progress of an asthmatic mouse model and its effect on Tfh and Breg cells. Methods: We synthesized and purified rAlt a 1. Alternaria-sensitized and challenged mice received subcutaneous immunotherapy (SCIT) with four different rAlt a 1 dosages (5, 50, 100, and 150 µg) or PBS only. Finally, lung and airway inflammation, mouse mast cell protease 1 (MMCP-1), serum immunoglobulin responses, Tfh and Breg cell levels, and the correlation between asthmatic features (inflammation grades and IL-4 and IL-10 levels) and these two cell types were measured after Alternaria rechallenge. Results: High purity and allergenic potency of rAlt a 1 protein were obtained. Following treatment with four different rAlt a 1 dosages, both lung and airway inflammation ameliorated, including lung pathology, serum MMCP-1 levels, inflammatory cell numbers, and cytokine levels in bronchoalveolar lavage fluid (BALF). Additionally, rAlt a 1-SCIT increased the expression of Alternaria-sIgG1, rAlt a 1-sIgG1, rAlt a 1-sIgG2a, and rAlt a 1-sIgG2b in serum. Moreover, the number and percentage of CXCR5+PD-1+Tfh cells were increased in the PC control, while they decreased in the rAlt a 1-SCIT groups. Meanwhile, the absolute numbers and proportions of Breg cells were evaluated after administration of rAlt a 1. A positive correlation was observed between CXCR5+PD-1+Tfh cells and inflammation grades (r = 0.50, p = 0.01), as well as a slightly strong positive relationship with IL-4 (r = 0.55, p = 0.005) and IL-10 (r = 0.58, p = 0.003) levels; Breg cells showed an opposite correlation with the grades of inflammation (r = -0.68, p = 0.0003), along with a negative correlation to IL-4 (r = -0.61, p = 0.001) and IL-10 (r = -0.53, p = 0.008) levels. Conclusions: We verified that treatment with rAlt a 1 can alleviate asthma progression and further have a regulatory effect on Tfh and Breg cells in an Alternaria-induced asthmatic mouse model.


Assuntos
Alternaria/imunologia , Antígenos de Fungos/imunologia , Asma/imunologia , Dessensibilização Imunológica/métodos , Hipersensibilidade/imunologia , Alérgenos/imunologia , Animais , Asma/etiologia , Linfócitos B Reguladores/imunologia , Hipersensibilidade/etiologia , Injeções Subcutâneas , Camundongos , Proteínas Recombinantes/imunologia , Células T Auxiliares Foliculares/imunologia
7.
J Exp Med ; 218(10)2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34410304

RESUMO

Löfgren's syndrome (LS) is an acute form of sarcoidosis characterized by a genetic association with HLA-DRB1*03 (HLA-DR3) and an accumulation of CD4+ T cells of unknown specificity in the bronchoalveolar lavage (BAL). Here, we screened related LS-specific TCRs for antigen specificity and identified a peptide derived from NAD-dependent histone deacetylase hst4 (NDPD) of Aspergillus nidulans that stimulated these CD4+ T cells in an HLA-DR3-restricted manner. Using ELISPOT analysis, a greater number of IFN-γ- and IL-2-secreting T cells in the BAL of DR3+ LS subjects compared with DR3+ control subjects was observed in response to the NDPD peptide. Finally, increased IgG antibody responses to A. nidulans NDPD were detected in the serum of DR3+ LS subjects. Thus, our findings identify a ligand for CD4+ T cells derived from the lungs of LS patients and suggest a role of A. nidulans in the etiology of LS.


Assuntos
Aspergillus nidulans/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Epitopos de Linfócito T/imunologia , Sarcoidose/imunologia , Adulto , Animais , Antígenos de Fungos/imunologia , Estudos de Casos e Controles , Feminino , Proteínas Fúngicas/imunologia , Antígeno HLA-DR3/química , Antígeno HLA-DR3/genética , Antígeno HLA-DR3/imunologia , Humanos , Hibridomas/imunologia , Imunoglobulina G , Masculino , Camundongos Transgênicos , Pessoa de Meia-Idade
8.
Front Immunol ; 12: 709695, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367172

RESUMO

Cryptococcus neoformans, an opportunistic fungal pathogen ubiquitously present in the environment, causes cryptococcal meningitis (CM) mainly in immunocompromised patients, such as AIDS patients. We aimed to identify disease-associated cryptococcal protein antigens targeted by the human humoral immune response. Therefore, we used sera from Colombian CM patients, with or without HIV infection, and from healthy individuals living in the same region. Serological analysis revealed increased titers of anti-cryptococcal IgG in HIV-negative CM patients, but not HIV-positive CM patients, compared to healthy controls. In contrast, titers of anti-cryptococcal IgM were not affected by CM. Furthermore, we detected pre-existing IgG and IgM antibodies even in sera from healthy individuals. The observed induction of anti-cryptococcal IgG but not IgM during CM was supported by analysis of sera from C. neoformans-infected mice. Stronger increase in IgG was found in wild type mice with high lung fungal burden compared to IL-4Rα-deficient mice showing low lung fungal burden. To identify the proteins targeted by human anti-cryptococcal IgG antibodies, we applied a quantitative 2D immunoproteome approach identifying cryptococcal protein spots preferentially recognized by sera from CM patients or healthy individuals followed by mass spectrometry analysis. Twenty-three cryptococcal proteins were recombinantly expressed and confirmed to be immunoreactive with human sera. Fourteen of them were newly described as immunoreactive proteins. Twelve proteins were classified as disease-associated antigens, based on significantly stronger immunoreactivity with sera from CM patients compared to healthy individuals. The proteins identified in our screen significantly expand the pool of cryptococcal proteins with potential for (i) development of novel anti-cryptococcal agents based on implications in cryptococcal virulence or survival, or (ii) development of an anti-cryptococcal vaccine, as several candidates lack homology to human proteins and are localized extracellularly. Furthermore, this study defines pre-existing anti-cryptococcal immunoreactivity in healthy individuals at a molecular level, identifying target antigens recognized by sera from healthy control persons.


Assuntos
Anticorpos Antifúngicos/imunologia , Cryptococcus neoformans/imunologia , Proteínas Fúngicas/imunologia , Imunoglobulina G/sangue , Meningite Criptocócica/imunologia , Adolescente , Adulto , Idoso , Animais , Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Criança , Feminino , Infecções por HIV/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Adulto Jovem
9.
Cells ; 10(7)2021 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-34359982

RESUMO

Paracoccidioidomycosis (PCM) is a systemic disease caused by Paracoccidioides spp. PCM is endemic in Latin America and most cases are registered in Brazil. This mycosis affects mainly the lungs, but can also spread to other tissues and organs, including the liver. Several approaches have been investigated to improve treatment effectiveness and protection against the disease. Extracellular vesicles (EVs) are good antigen delivery vehicles. The present work aims to investigate the use of EVs derived from Paracoccidioides brasiliensis as an immunization tool in a murine model of PCM. For this, male C57BL/6 were immunized with two doses of EVs plus adjuvant and then infected with P. brasiliensis. EV immunization induced IgM and IgG in vivo and cytokine production by splenocytes ex vivo. Further, immunization with EVs had a positive effect on mice infected with P. brasiliensis, as it induced activated T lymphocytes and NKT cell mobilization to the infected lungs, improved production of proinflammatory cytokines and the histopathological profile, and reduced fungal burden. Therefore, the present study shows a new role for P. brasiliensis EVs in the presence of adjuvant as modulators of the host immune system, suggesting their utility as immunizing agents.


Assuntos
Antígenos de Fungos/imunologia , Vesículas Extracelulares/microbiologia , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/microbiologia , Substâncias Protetoras/farmacologia , Animais , Anticorpos Antifúngicos/imunologia , Movimento Celular , Citocinas/metabolismo , Vesículas Extracelulares/efeitos dos fármacos , Imunização , Memória Imunológica , Pulmão/microbiologia , Pulmão/patologia , Ativação Linfocitária/imunologia , Masculino , Camundongos Endogâmicos C57BL , Células T Matadoras Naturais/imunologia , Padrões de Referência
10.
J Extracell Vesicles ; 10(10): e12129, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34377375

RESUMO

Whereas extracellular vesicle (EV) research has become commonplace in different biomedical fields, this field of research is still in its infancy in mycology. Here we provide a robust set of data regarding the structural and compositional aspects of EVs isolated from the fungal pathogenic species Cryptococcus neoformans, C. deneoformans and C. deuterogattii. Using cutting-edge methodological approaches including cryogenic electron microscopy and cryogenic electron tomography, proteomics, and flow cytometry, we revisited cryptococcal EV features and suggest a new EV structural model, in which the vesicular lipid bilayer is covered by mannoprotein-based fibrillar decoration, bearing the capsule polysaccharide as its outer layer. About 10% of the EV population is devoid of fibrillar decoration, adding another aspect to EV diversity. By analysing EV protein cargo from the three species, we characterized the typical Cryptococcus EV proteome. It contains several membrane-bound protein families, including some Tsh proteins bearing a SUR7/PalI motif. The presence of known protective antigens on the surface of Cryptococcus EVs, resembling the morphology of encapsulated virus structures, suggested their potential as a vaccine. Indeed, mice immunized with EVs obtained from an acapsular C. neoformans mutant strain rendered a strong antibody response in mice and significantly prolonged their survival upon C. neoformans infection.


Assuntos
Cryptococcus neoformans/imunologia , Cryptococcus neoformans/metabolismo , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Vacinas/imunologia , Motivos de Aminoácidos , Animais , Antígenos de Fungos/imunologia , Antígenos de Fungos/metabolismo , Microscopia Crioeletrônica , Criptococose/imunologia , Vesículas Extracelulares/microbiologia , Feminino , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteoma , Proteômica/métodos
11.
Immunology ; 164(3): 587-601, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34287854

RESUMO

Sepsis is a life-threatening condition involving a dysregulated immune response to infectious agents that cause injury to host tissues and organs. Current treatments are limited to early administration of antibiotics and supportive care. While appealing, the strategy of targeted inhibition of individual molecules in the inflammatory cascade has not proved beneficial. Non-targeted, systemic immunosuppression with steroids has shown limited efficacy and raises concern for secondary infection. Iminosugars are a class of small molecule glycomimetics with distinct inhibition profiles for glycan processing enzymes based on stereochemistry. Inhibition of host endoplasmic reticulum resident glycoprotein processing enzymes has demonstrated efficacy as a broad-spectrum antiviral strategy, but limited consideration has been given to the effects on host glycoprotein production and consequent disruption of signalling cascades. This work demonstrates that iminosugars inhibit dengue virus, bacterial lipopolysaccharide and fungal antigen-stimulated cytokine responses in human macrophages. In spite of decreased inflammatory mediator production, viral replication is suppressed in the presence of iminosugar. Transcriptome analysis reveals the key interaction of pathogen-induced endoplasmic reticulum stress, the resulting unfolded protein response and inflammation. Our work shows that iminosugars modulate these interactions. Based on these findings, we propose a new therapeutic role for iminosugars as treatment for sepsis-related inflammatory disorders associated with excess cytokine secretion.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Sepse/tratamento farmacológico , Resposta a Proteínas não Dobradas/efeitos dos fármacos , 1-Desoxinojirimicina/farmacologia , 1-Desoxinojirimicina/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Antígenos de Fungos/imunologia , Células Cultivadas , Vírus da Dengue/imunologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/microbiologia , Lipopolissacarídeos/imunologia , Macrófagos , Cultura Primária de Células , Sepse/imunologia , Sepse/microbiologia , Receptor 4 Toll-Like/metabolismo , Resposta a Proteínas não Dobradas/imunologia
12.
Nature ; 596(7870): 114-118, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34262174

RESUMO

Pathogenic fungi reside in the intestinal microbiota but rarely cause disease. Little is known about the interactions between fungi and the immune system that promote commensalism. Here we investigate the role of adaptive immunity in promoting mutual interactions between fungi and host. We find that potentially pathogenic Candida species induce and are targeted by intestinal immunoglobulin A (IgA) responses. Focused studies on Candida albicans reveal that the pathogenic hyphal morphotype, which is specialized for adhesion and invasion, is preferentially targeted and suppressed by intestinal IgA responses. IgA from mice and humans directly targets hyphal-enriched cell-surface adhesins. Although typically required for pathogenesis, C. albicans hyphae are less fit for gut colonization1,2 and we show that immune selection against hyphae improves the competitive fitness of C. albicans. C. albicans exacerbates intestinal colitis3 and we demonstrate that hyphae and an IgA-targeted adhesin exacerbate intestinal damage. Finally, using a clinically relevant vaccine to induce an adhesin-specific immune response protects mice from C. albicans-associated damage during colitis. Together, our findings show that adaptive immunity suppresses harmful fungal effectors, with benefits to both C. albicans and its host. Thus, IgA uniquely uncouples colonization from pathogenesis in commensal fungi to promote homeostasis.


Assuntos
Imunidade Adaptativa , Candida albicans/imunologia , Candida albicans/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Simbiose/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Fungos/imunologia , Candida albicans/patogenicidade , Colite/imunologia , Colite/microbiologia , Colite/patologia , Feminino , Vacinas Fúngicas/imunologia , Microbioma Gastrointestinal/imunologia , Humanos , Hifas/imunologia , Imunoglobulina A/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
13.
PLoS One ; 16(7): e0253781, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34242263

RESUMO

BACKGROUND: Up to 15% of deaths of people living with HIV is attributable to meningeal cryptococcosis, with nearly 75% occuring in sub-Saharan Africa. Although rare in children, it is a major cause of morbidity and mortality in people living with HIV. A strong association between cryptococcal antigenemia and the development of meningeal cryptococcosis has been shown in adults. Thus, in 2018, the World Health Organization published an updated version of its guidelines for the diagnosis, prevention and management of cryptococcal infection in adults, adolescents and the HIV-infected child. GOAL: To determine the prevalence of cryptococcal antigenemia and to identify its determinants in children infected with HIV. METHODS: An analytical cross-sectional study was carried out at the approved treatment center of Laquintinie hospital in Douala over a period of 4 months. Children were recruited consecutively after informed parental consent. Cryptococcal antigenemia and CD4 assay were performed using a Cryptops® immunochromatographic rapid diagnostic test and flow cytometry, respectively. The data collected included the socio-demographic, clinical and paraclinical variables of the children, as well as their antecedents. Data analysis was performed using Epiinfo software version 3.1 and SPSS 21.0. The significance threshold was set at 5%. RESULTS: A total of 147 children were enrolled. The mean age was 9.8 ± 4.09 years. The majority were on antiretroviral therapy (142, 96.60%). Only 13 (8.80%) were in severe immunosuppression. No child showed signs of meningeal cryptococcosis. The prevalence of cryptococcal antigenemia was 6.12%. Severe immunosuppression [OR: 10.03 (1.52-65.91), p = 0.016] and contact with pigeons [OR: 9.76 (1.14-83.65), p = 0.037] were independent factors significantly associated with the carriage of the cryptococcal antigen. CONCLUSION: We recommend screening for cryptococcal antigenemia and routine treatment with fluconazole of all HIV positive children with cryptococcal antigen whether symptomatic or not.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Antígenos de Fungos/sangue , Portador Sadio/epidemiologia , Criptococose/epidemiologia , Cryptococcus/isolamento & purificação , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Adolescente , Antígenos de Fungos/imunologia , Camarões/epidemiologia , Portador Sadio/sangue , Portador Sadio/imunologia , Portador Sadio/microbiologia , Criança , Pré-Escolar , Estudos Transversais , Criptococose/sangue , Criptococose/imunologia , Criptococose/microbiologia , Cryptococcus/imunologia , Feminino , Humanos , Lactente , Masculino , Prevalência
14.
J Immunol ; 207(3): 923-937, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34301842

RESUMO

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by genetic defects in leukocyte NADPH oxidase, which has both microbicidal and immunomodulatory roles. Hence, CGD is characterized by recurrent bacterial and fungal infections as well as aberrant inflammation. Fungal cell walls induce neutrophilic inflammation in CGD; yet, underlying mechanisms are incompletely understood. This study investigated the receptors and signaling pathways driving aberrant proinflammatory cytokine production in CGD neutrophils activated by fungal cell walls. Although cytokine responses to ß-glucan particles were similar in NADPH oxidase-competent and NADPH oxidase-deficient mouse and human neutrophils, stimulation with zymosan, a more complex fungal particle, induced elevated cytokine production in NADPH oxidase-deficient neutrophils. The dectin-1 C-type lectin receptor, which recognizes ß-glucans (1-3), and TLRs mediated cytokine responses by wild-type murine neutrophils. In the absence of NADPH oxidase, fungal pathogen-associated molecular patterns engaged additional collaborative signaling with Mac-1 and TLRs to markedly increase cytokine production. Mechanistically, this cytokine overproduction is mediated by enhanced proximal activation of tyrosine phosphatase SHP2-Syk and downstream Card9-dependent NF-κB and Card9-independent JNK-c-Jun. This activation and amplified cytokine production were significantly decreased by exogenous H2O2 treatment, enzymatic generation of exogenous H2O2, or Mac-1 blockade. Similar to zymosan, Aspergillus fumigatus conidia induced increased signaling in CGD mouse neutrophils for activation of proinflammatory cytokine production, which also used Mac-1 and was Card9 dependent. This study, to our knowledge, provides new insights into how NADPH oxidase deficiency deregulates neutrophil cytokine production in response to fungal cell walls.


Assuntos
Aspergillus fumigatus/fisiologia , Doença Granulomatosa Crônica/imunologia , Lectinas Tipo C/metabolismo , Antígeno de Macrófago 1/metabolismo , NADPH Oxidase 2/metabolismo , Neutrófilos/imunologia , Receptores de Reconhecimento de Padrão/metabolismo , Animais , Antígenos de Fungos/imunologia , Células Cultivadas , Citocinas/metabolismo , Doença Granulomatosa Crônica/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidase 2/genética , NF-kappa B/metabolismo , Ativação de Neutrófilo , Moléculas com Motivos Associados a Patógenos/imunologia , Receptor Cross-Talk , Transdução de Sinais , beta-Glucanas/imunologia
15.
Ann Clin Lab Sci ; 51(3): 430-433, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34162576

RESUMO

Cryptococcus is a basidiomycetous yeast responsible for considerable HIV-related morbidity and mortality. A cachectic 26-year-old HIV-positive man with a CD4 count of 103 cells/µl presented with fever, breathlessness, and bilateral lower limb weakness. A brain computed tomography scan could not elucidate the neurological deficit. His blood was sent for culture and serum cryptococcal antigen detection, with the latter testing as negative. By the fourth day of admission, the patient's condition had deteriorated drastically. A lumbar puncture was performed, and like his serum sample, the cerebrospinal fluid also tested negative for cryptococcal antigens. By this time, Cryptococcus neoformans was isolated from the admission blood culture. The laboratory diluted both the serum and cerebrospinal fluid specimens to retest for cryptococcal antigens, and finally, an antigen titer of ≥1:2560 was recorded.


Assuntos
Antígenos de Fungos/imunologia , Criptococose/diagnóstico , Cryptococcus/imunologia , Infecções por HIV/complicações , Adulto , Contagem de Linfócito CD4 , Criptococose/microbiologia , Criptococose/virologia , Cryptococcus/isolamento & purificação , Reações Falso-Negativas , HIV/fisiologia , Infecções por HIV/virologia , Humanos , Masculino
16.
BMC Immunol ; 22(1): 40, 2021 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-34174820

RESUMO

BACKGROUND: Pneumocystis pneumonia (PcP), which is caused by Pneumocystis carinii, is a life-threatening infection that affects immunocompromised individuals. Unfortunately, chemoprophylaxis and dapsone are only effective for half of the patients with PcP, indicating that additional preventive methods are needed. We predicated the pneumocystis surface protein A12 sequence 1-85 by DNAStar software and BepiPred, and identified it as a potential vaccine candidate by bioresearch. METHODS: We used recombinant A121-85 as antigen to immunized mice and detected serum titer of IgG, expression of inflammatory factors by EILSA, qRT-PCR and flow cytometry. RESULTS: Our results showed that immunization with recombinant A121-85 increased the serum titer of IgG, promoted the secretion of T lymphocytes, increased the expression of inflammatory factors, and elevated lung inflammatory injury in mice. CONCLUSIONS: Our findings suggest that A121-85 is a potential vaccine target for preventing Pneumocystis carinii. The evaluation of A121-85-elicited antibodies in the prevention of PcP in humans deserves further investigation.


Assuntos
Antígenos de Fungos/imunologia , Vacinas Fúngicas/imunologia , Pulmão/imunologia , Pneumocystis carinii/fisiologia , Pneumonia por Pneumocystis/prevenção & controle , Linfócitos T/imunologia , Animais , Anticorpos Antifúngicos/sangue , Antígenos de Fungos/uso terapêutico , Células Cultivadas , Modelos Animais de Doenças , Feminino , Vacinas Fúngicas/administração & dosagem , Humanos , Imunização , Hospedeiro Imunocomprometido , Imunoglobulina G/sangue , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/genética , Peptídeos/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia
17.
J Drugs Dermatol ; 20(5): 546-549, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33938709

RESUMO

BACKGROUND: Warts, or verrucae, are mucosal human papilloma virus (HPV) infections that are very challenging to treat. OBJECTIVE: To compare the safety and efficacy of intralesional injection of vitamin D3 versus intralesional injection of candida albicans antigen for plantar warts. METHODS: Forty patients were included in the study and were divided into two groups (A&B) with 20 patients each. Group A received intralesional vitamin D3 while Group B received intralesional Candida antigen. Injection was done every 3 weeks until clearance of warts or a maximum of three treatments. RESULTS: Nine patients showed complete clearance in group A (45%), while 6 patients (30%) showed partial response and no response in 5 patients (25%) of group (A). As for group (B), complete clearance of the treated warts was observed in 8 patients (40%), partial response in 6 patients (30%) while no response was observed in 6 patients (30%). No superiority of one treatment to the other was observed nor was any statistical significance in both groups’ responses noted. CONCLUSION: Treatment of multiple warts by intralesional injection of candida antigen or vitamin D3 is safe and effective, with good cure rates, has an excellent safety profile, with minimal recurrences and statistically equivalent. J Drugs Dermatol. 2021;20(5):546-549. doi:10.36849/JDD.5264.


Assuntos
Antígenos de Fungos/administração & dosagem , Candida albicans/imunologia , Colecalciferol/administração & dosagem , Imunoterapia/métodos , Verrugas/tratamento farmacológico , Adulto , Antígenos de Fungos/efeitos adversos , Antígenos de Fungos/imunologia , Colecalciferol/efeitos adversos , Feminino , Seguimentos , Humanos , Imunoterapia/efeitos adversos , Injeções Intralesionais , Masculino , Resultado do Tratamento , Verrugas/imunologia , Adulto Jovem
18.
Pol J Microbiol ; 70(1): 3-11, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815522

RESUMO

Aspergillus fumigatus is one of the ubiquitous fungi with airborne conidia, which accounts for most aspergillosis cases. In immunocompetent hosts, the inhaled conidia are rapidly eliminated. However, immunocompromised or immunodeficient hosts are particularly vulnerable to most Aspergillus infections and invasive aspergillosis (IA), with mortality from 50% to 95%. Despite the improvement of antifungal drugs over the last few decades, the therapeutic effect for IA patients is still limited and does not provide significant survival benefits. The drawbacks of antifungal drugs such as side effects, antifungal drug resistance, and the high cost of antifungal drugs highlight the importance of finding novel therapeutic and preventive approaches to fight against IA. In this article, we systemically addressed the pathogenic mechanisms, defense mechanisms against A. fumigatus, the immune response, molecular aspects of host evasion, and vaccines' current development against aspergillosis, particularly those based on AFMP4 protein, which might be a promising antigen for the development of anti-A. fumigatus vaccines.


Assuntos
Antígenos de Fungos/imunologia , Aspergilose/imunologia , Aspergillus fumigatus/imunologia , Proteínas Fúngicas/imunologia , Vacinas Fúngicas/imunologia , Animais , Antígenos de Fungos/administração & dosagem , Antígenos de Fungos/genética , Aspergilose/microbiologia , Aspergilose/prevenção & controle , Aspergillus fumigatus/genética , Aspergillus fumigatus/patogenicidade , Proteínas Fúngicas/administração & dosagem , Proteínas Fúngicas/genética , Vacinas Fúngicas/administração & dosagem , Vacinas Fúngicas/genética , Humanos , Imunidade , Virulência
19.
PLoS One ; 16(4): e0250195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33901215

RESUMO

BACKGROUND: Cryptococcal meningitis is a leading cause of HIV-related mortality in sub-Saharan Africa, however, screening for cryptococcal antigenemia has not been universally implemented. As a result, data concerning cryptococcal meningitis and antigenemia are sparse, and in Mozambique, the prevalence of both are unknown. METHODS: We performed a retrospective analysis of routinely collected data from a point-of-care cryptococcal antigen screening program at a public hospital in Maputo, Mozambique. HIV-positive patients admitted to the emergency department underwent CD4 count testing; those with pre-defined abnormal vital signs or CD4 count ≤ 200 cells/µL received cryptococcal antigen testing and lumbar punctures if indicated. Patients with CM were admitted to the hospital and treated with liposomal amphotericin B and flucytosine; their 12-week outcomes were ascertained through review of medical records or telephone contact by program staff made in the routine course of service delivery. RESULTS: Among 1,795 patients screened for cryptococcal antigenemia between March 2018-March 2019, 134 (7.5%) were positive. Of patients with cryptococcal antigenemia, 96 (71.6%) were diagnosed with CM, representing 5.4% of all screened patients. Treatment outcomes were available for 87 CM patients: 24 patients (27.6%) died during induction treatment and 63 (72.4%) survived until discharge; of these, 38 (60.3%) remained in care, 9 (14.3%) died, and 16 (25.3%) were lost-to follow-up at 12 weeks. CONCLUSIONS: We found a high prevalence of cryptococcal antigenemia and meningitis among patients screened at an emergency department in Maputo, Mozambique. High mortality during and after induction therapy demonstrate missed opportunities for earlier detection of cryptococcal antigenemia, even as point-of-care screening and rapid assessment in an emergency room offer potential to improve outcomes.


Assuntos
Cryptococcus/imunologia , Meningite Criptocócica/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , Antígenos de Fungos/imunologia , Criptococose/epidemiologia , Cryptococcus/metabolismo , Cryptococcus/patogenicidade , Serviço Hospitalar de Emergência , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Meningite/diagnóstico , Meningite/epidemiologia , Meningite Criptocócica/diagnóstico , Pessoa de Meia-Idade , Moçambique , Prevalência , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
20.
PLoS Negl Trop Dis ; 15(4): e0009317, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33826630

RESUMO

BACKGROUND: Paracoccidioidomycosis (PCM) is a systemic and endemic fungal infection in Latin American, mainly in Brazil. The majority of PCM cases occur in large areas in Brazil, comprising the South, Southeast and Midwest regions, with the latter demonstrating a higher incidence of the species Paracoccidioides lutzii. METHODOLOGY AND MAIN FINDINGS: This study presents clinical, molecular and serological data of thirteen new PCM cases during 2016 to 2019 from the state of Mato Grosso do Sul, located in the Midwest region, Brazil. From these thirteen cases, sixteen clinical isolates were obtained and their genomic DNAs were subjected to genotyping by tub1 -PCR-RFLP. Results showed Paracoccidioides brasiliensis sensu stricto (S1) (11/16; 68.8%), Paracoccidioides restrepiensis (PS3) (4/16; 25.0%) and P. lutzii (1/16; 6.2%) as Paracoccidiodes species. Therefore, in order to understand whether the type of phylogenetic species that are circulating in the state influence the reactivity profile of serological tests, we performed double agar gel immunodiffusion (DID), using exoantigens from genotyped strains found in this series of PCM cases. Overall, our DID tests have been false negative in about 30% of confirmed PCM cases. All patients were male, most with current or previous rural activity, with ages ranging from 17 to 59 years, with 11 patients (84.6%) over 40 years of age. No clinical or epidemiological differences were found between Paracoccidioides species. However, it is important to note that the only case of P. lutzii died as an outcome. CONCLUSIONS: This study suggests P. brasiliensis sensu stricto (S1) as the predominant species, showing its wide geographic distribution in Brazil. Furthermore, our findings revealed, for the first time, the occurrence of P. restrepiensis (PS3) in the state of Mato Grosso do Sul, Brazil. Despite our setbacks, it would be interesting to provide the complete sequencing of these clinical isolates to complement the molecular information presented.


Assuntos
Antígenos de Fungos/imunologia , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/microbiologia , Adolescente , Adulto , Anticorpos Antifúngicos/imunologia , Brasil/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Paracoccidioides/classificação , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/diagnóstico , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sorotipagem , Adulto Jovem
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