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1.
Microb Pathog ; 166: 105539, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35447314

RESUMO

Sporotrichosis is a cosmopolitan mycosis caused by pathogenic species of Sporothrix genus, that in Brazil is often acquired by zoonotic transmission involved infected cats with S. brasiliensis. Previous studies showed that the Sporothrix spp. recombinant enolase (rSsEno), a multifunctional protein with immunogenic properties, could be a promising target for vaccination against sporotrichosis in cats. Nevertheless, the considerable sequence identity (62%) of SsEno with its feline counterpart is a great concern. Here, we report the identification in silico, chemical synthesis and biological validation of six peptides of SsEno with low sequence identity to its cat orthologue. All synthesized peptides exhibit B-cell epitopes on the molecular surface of SsEno and proved to be highly reactive with the serum of infected mice with S. brasiliensis and sera of cats with sporotrichosis. Interestingly, our study revealed that anti-peptide sera did not react with the recombinant enolase from Felis catus (cats, rFcEno), thus, may not trigger autoimmune response in these felines if used as a vaccine antigen. The immunization with peptide mixture (PeptMix) formulated with Freund adjuvant (FA), induced high levels of antigen-specific IgG, IgG1 and IgG2b antibodies that conferred protection upon passive transference in infected BALB/c mice with S. brasiliensis. We also observed, that the FA+PeptMix formulation induced a Th1/Th2/Th17 cytokine profile ex vivo, associated with protecting effect against the experimental sporotrichosis. Our results suggest that the six SsEno-derived peptides here evaluated, could be used as safe antigens for the development of vaccine strategies against feline sporotrichosis, whether prophylactic or therapeutic.


Assuntos
Vacinas Fúngicas , Fosfopiruvato Hidratase , Esporotricose , Animais , Brasil , Gatos , Epitopos , Vacinas Fúngicas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/imunologia , Sporothrix/enzimologia , Sporothrix/genética , Esporotricose/prevenção & controle
2.
Immunology ; 155(4): 467-476, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30030839

RESUMO

Natural killer (NK) cells are one of the first cell types to enter inflammation sites and have been historically known as key effector cells against tumours and viruses; now, accumulating evidence shows that NK cells are also capable of direct in vitro activity and play a protective role against clinically important fungi in vivo. However, our understanding of NK cell development, maturation and activation in the setting of fungal infections is preliminary at best. Sporotrichosis is an emerging worldwide-distributed subcutaneous mycosis endemic in many countries, affecting humans and other animals and caused by various related thermodimorphic Sporothrix species, whose prototypical member is Sporothrix schenckii. We show that following systemic infection of BALB/c mice with S. schenckii sensu stricto, NK cells displayed a more mature phenotype as early as 5 days post-infection as judged by CD11b/CD27 expression. At 10 days post-infection, NK cells had increased expression of CD62 ligand (CD62L) and killer cell lectin-like receptor subfamily G member 1 (KLRG1), but not of CD25 or CD69. Depletion of NK cells with anti-asialo GM1 drastically impaired fungal clearance, leading to a more than eightfold increase in splenic fungal load accompanied by heightened systemic inflammation, as shown by augmented production of the pro-inflammatory cytokines tumour necrosis factor-α, interferon-γ and interleukin-6, but not interleukin-17A, in the spleen and serum. Our study is, to the best of our knowledge, the first to demonstrate that a fungal infection can drive NK cell maturation in vivo and that such cells are pivotal for in vivo protection against S. schenckii.


Assuntos
Células Matadoras Naturais/imunologia , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Antígenos CD/sangue , Antígenos de Diferenciação de Linfócitos T/sangue , Antígenos CD11/sangue , Diferenciação Celular/imunologia , Interferon gama/biossíntese , Interleucina-17/biossíntese , Subunidade alfa de Receptor de Interleucina-2/sangue , Interleucina-6/biossíntese , Células Matadoras Naturais/citologia , Selectina L/sangue , Lectinas Tipo C/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Receptores Imunológicos/sangue , Esporotricose/microbiologia , Esporotricose/patologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/biossíntese
3.
Pharmacol Res ; 129: 237-250, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29175113

RESUMO

Adjuvants are substances used to enhance the efficacy of vaccines. They influence the magnitude and alter the quality of the adaptive immune response to vaccine antigens by amplifying or modulating different signals involved in the innate immune response. The majority of known adjuvants have been empirically identified. The limited immunogenicity of new vaccine antigens and the need for safer vaccines have increased the importance of identifying single, well-defined adjuvants with known cellular and molecular mechanisms for rational vaccine design. Depletion or functional inhibition of CD4+CD25+FoxP3+ regulatory T cells (Tregs) by molecular adjuvants has become an emergent approach in this field. Different successful results have been obtained for specific vaccines, but there are still unresolved issues such as the risk of autoimmune disease induction, the involvement of cells other than Tregs and optimization for different conditions. This work provides a comprehensive analysis of current approaches to inhibit Tregs with molecular adjuvants for vaccine improvement, highlights the progress being made, and describes ongoing challenges.


Assuntos
Adjuvantes Imunológicos/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Vacinação , Animais , Humanos , Tolerância Imunológica , Medição de Risco , Linfócitos T Reguladores/imunologia
4.
Med Mycol ; 56(6): 711-722, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29087533

RESUMO

This report describes a model of host resistance for Sporothrix schenckii, an opportunistic fungi in immunosuppressed mice with cyclophosphamide (CY) to be used in studies of immunotoxicology and immunopharmacology. Two doses of CY were administered intraperitoneally: 200 mg/kg and a booster of 150 mg/kg at 9-day intervals. Three days after the first dose of CY the animals were infected subcutaneously with 1.8 × 108 yeast/ml (S. schenckii ATCC 16345). At 7 and 14 days post-infection, the animals were euthanized and analyzed the fungal load by unit forming colony count in the spleen and popliteal lymph nodes. The relative weight of thymus and spleen, splenic index, the frequency of T and B cells in spleen by flow cytometry, the hind paw inflammation index and cytokine (interleukin [IL]-17, IL-10, and interferon [IFN]-γ) profile were measured. Histopathological studies of the spleen and the hind paw were also assessed. The immunosuppression status was confirmed at the evaluated days by reduction of relative weight of thymus, reduction of the splenic white pulp, the population of B and T lymphocytes, and the cytokine profile in the treated mice with CY in comparison with nontreated groups, associated to higher fungal load in hind paw and spleen in the infected mice. The described model reveals an increasing in susceptibility to infection and severity when associated with immunosuppression. This model can serve as a reference for studies of S. schenckii host resistance in pharmaceutical and toxicological studies.


Assuntos
Sporothrix/imunologia , Esporotricose/imunologia , Animais , Contagem de Colônia Microbiana , Ciclofosfamida/administração & dosagem , Citocinas/metabolismo , Modelos Animais de Doenças , Hospedeiro Imunocomprometido , Imunossupressores/administração & dosagem , Linfonodos/imunologia , Linfonodos/microbiologia , Linfonodos/patologia , Subpopulações de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologia , Baço/microbiologia , Baço/patologia , Esporotricose/microbiologia , Esporotricose/patologia
5.
Immunology ; 151(2): 154-166, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28140444

RESUMO

Sporotrichosis is a mycosis caused by fungi from the Sporothrix schenckii species complex, whose prototypical member is Sporothrix schenckii sensu stricto. Pattern recognition receptors (PRRs) recognize and respond to pathogen-associated molecular patterns (PAMPs) and shape the following adaptive immune response. A family of PRRs most frequently associated with fungal recognition is the nucleotide-binding oligomerization domain-like receptor (NLR). After PAMP recognition, NLR family pyrin domain-containing 3 (NLRP3) binds to apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and caspase-1 to form the NLRP3 inflammasome. When activated, this complex promotes the maturation of the pro-inflammatory cytokines interleukin-1ß (IL-1ß) and IL-18 and cell death through pyroptosis. In this study, we aimed to evaluate the importance of the NLRP3 inflammasome in the outcome of S. schenckii infection using the following three different knockout (KO) mice: NLRP3-/- , ASC-/- and caspase-1-/- . All KO mice were more susceptible to infection than the wild-type, suggesting that NLRP3-triggered responses contribute to host protection during S. schenckii infection. Furthermore, the NLRP3 inflammasome appeared to be critical for the ex vivo release of IL-1ß, IL-18 and IL-17 but not interferon-γ. Additionally, a role for the inflammasome in shaping the adaptive immune response was suggested by the lower frequencies of type 17 helper T (Th17) cells and Th1/Th17 but not Th1 cells in S. schenckii-infected KO mice. Overall, our results indicate that the NLRP3 inflammasome links the innate recognition of S. schenckii to the adaptive immune response, so contributing to protection against this infection.


Assuntos
Inflamassomos/imunologia , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Sporothrix/citologia , Esporotricose/microbiologia
6.
Microb Pathog ; 110: 78-84, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28645771

RESUMO

The available information about the role of Dectin-1 in sporotrichosis is scarce. Hence, we aimed to assess Dectin-1 expression by macrophages and the activation of some related antifungal mechanisms during the Sporothrix schenckii sensu stricto infection as a first attempt to elucidate the role of this receptor in sporotrichosis. Balb/c mice were intraperitoneally infected with S. schenckii sensu stricto yeast ATCC 16345 and euthanized on days 5, 10 and 15 post-infection, when the following parameters were evaluated: fungal burden in spleen, Dectin-1 expression and nitric oxide (NO) production by peritoneal macrophages, as well as IL-1ß, TNF-α and IL-10 ex vivo secretion by these same cells. Peritoneal macrophages were ex vivo challenged with either the alkali-insoluble fraction (F1) extracted from the S. schenckii cell wall, a commercially available purified ß-1,3-glucan or whole heat-killed S. schenckii yeasts (HKss). Additionally, a Dectin-1 antibody-mediated blockade assay was performed on day 10 post-infection to assess the participation of this receptor in cytokine secretion. Our results showed that Dectin-1 expression by peritoneal macrophages was augmented on days 10 and 15 post-infection alongside elevated NO production and ex vivo secretion of IL-10, TNF-α and IL-1ß. The antibody-mediated blockade of Dectin-1 inhibited cytokine production in both infected and non-infected mice, mainly after ß-1,3-glucan stimulation. Our results suggest a role for Dectin-1 in triggering the immune response during S. schenckii infection.


Assuntos
Antifúngicos/farmacologia , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Sporothrix/efeitos dos fármacos , Sporothrix/patogenicidade , Esporotricose/imunologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Lectinas Tipo C/imunologia , Macrófagos/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Baço/microbiologia , Esporotricose/microbiologia , Fator de Necrose Tumoral alfa/metabolismo
7.
Mycopathologia ; 181(3-4): 207-15, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26603044

RESUMO

The response of hydrogen peroxide (H2O2) and cytokines during an experimental sporotrichosis in male Swiss mice was assessed over a period of 10 weeks by monitoring macrophage activation challenged with exoantigen (ExoAg) from the fungus Sporothrix schenckii. The studied endpoints were: H2O2 production, fungal burden at spleen, apoptosis in peritoneal macrophages, and IL-1ß, IL-6, IL-2, IL-10 production. During the two first weeks of infection was observed low burden of yeast in spleen and high response of H2O2, IL-2, and IL-1ß. The weeks of highest fungal burden (fourth-sixth) coincided with major apoptosis in peritoneal macrophages, normal production of IL-6 and lower production of H2O2, IL-2, and IL-1ß, suggesting a role for these three last in the early control of infection. On the other hand, IL-1ß (but not IL-6) was recovered since the sixth week, suggesting a possible role in the late phase of infection, contributing to the fungal clearance in conjunction with the specific mechanisms. The IL-10 was elevated until the sixth, principally in the second week. These results evidences that ExoAg is involved in the host immune modulation, influencing the S. Schenckii virulence, and its role is related with the time of the infection in the model used.


Assuntos
Antígenos de Fungos/imunologia , Peróxido de Hidrogênio/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-2/metabolismo , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Apoptose/imunologia , Ativação de Macrófagos/imunologia , Macrófagos Peritoneais/imunologia , Masculino , Camundongos , Óxido Nítrico/metabolismo , Esporotricose/microbiologia , Esporotricose/patologia
8.
Mycopathologia ; 179(1-2): 21-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25205196

RESUMO

Sporotrichosis is a chronic infection caused by the dimorphic fungus Sporothrix schenckii, involving all layers of skin and the subcutaneous tissue. The role of innate immune toll-like receptors 2 and 4 in the defense against this fungus has been reported, but so far, there were no studies on the effect of cell wall major components over the cytosolic oligo-merization domain (NOD)-like receptors, important regulators of inflammation and responsible for the maturation of IL-1ß and IL-18, whose functions are dependents of the caspase-1 activation, that can participate of inflammasome. It was evaluated the percentage of activation of caspase-1, the production of IL-1ß, IL-18, IL-17, IFN-γ and nitric oxide in a Balb/c model of S. schenckii infection. It was observed a decreased activity of caspase-1 during the fourth and sixth weeks of infection accompanied by reduced secretion of the cytokines IL-1ß, IL-18 and IL-17 and high production of nitric oxide. IFN-γ levels were elevated during the entire time course of infection. This temporal reduction in caspase-1 activity coincides exactly with the reported period of fungal burden associated with a transitory immunosuppression induced by this fungus and detected in similar infection models. These results indicate the importance of interaction between caspase-1, cytokines IL-1ß and IL-18 in the host defense against S. schenckii infection, suggesting a participation the inflammasome in this response.


Assuntos
Caspase 1/metabolismo , Interferon gama/biossíntese , Óxido Nítrico/biossíntese , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Parede Celular , Ativação Enzimática , Inflamassomos/imunologia , Interleucina-17/biossíntese , Interleucina-18/biossíntese , Interleucina-1beta/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pele/microbiologia , Pele/patologia
9.
Med Chem ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39082171

RESUMO

INTRODUCTION: Furoxan and benzofuroxan are compounds containing an N-oxide function, known for their diverse pharmacological properties, including antimicrobial and antiinflammatory effects. This study aimed to investigate these activities using an in-house library of N-oxide compounds. METHOD: Twenty compounds were tested against both Gram-positive and Gram-negative bacteria, including Cutibacterium acnes (C. acnes), a microorganism implicated in the development of acne vulgaris. One compound, (E)-4-(3-((2-(3-hydroxybenzoyl)hydrazone)methyl)phenoxy)-3- (phenylsulfonyl)-1,2,5-oxadiazol-2-N-oxide (compound 15), exhibited selective antimicrobial activity against C. acnes, with a Minimum Inhibitory Concentration (MIC) value of 2 µg/mL. Indirect measurement of Nitric Oxide (NO) release showed that compound 15 and isosorbide dinitrate, when treated with L-cysteine, produced nitrite levels of 20.1% and 9.95%, respectively. Using a NO scavenger (PTIO) in combination with compound 15 in a culture of C. acnes resulted in reduced antimicrobial activity, indicating that NO release is part of its mechanism of action. Cytotoxicity assessments using murine macrophages showed cellular viability above 70% at concentrations up to 0.78 µg/mL. RESULTS: Measurements of Interleukin-1 beta (IL1-ß) and Tumor Necrosis Factor-alpha (TNF-α) indicated that compound 15 did not reduce the levels of these pro-inflammatory cytokines. Sustained NO production by inducible Nitric Oxide Synthase (iNOS) in macrophages or neutrophils has been found to be involved in the inflammatory process in acne vulgaris and lead to toxicity in surrounding tissues. Nitrite levels in the supernatant of murine macrophages were found to be decreased at a concentration of 0.78 µg/mL of compound 15, indicating an anti-inflammatory effect. In vivo studies were conducted using Balb/c nude mice inoculated subcutaneously with C. acnes. Cream and gel formulations of compound 15 were applied to treat the animals, along with commercially available anti-acne drugs, for 14 days. Animals treated with a cream base containing 5% of compound 15 exhibited less acanthosis with mild inflammatory infiltration compared to other groups, highlighting its anti-inflammatory properties. CONCLUSION: Similar results were observed in the benzoyl peroxide group, demonstrating that compound 15 presented comparable anti-inflammatory activity to the FDA-approved drug. These promising results suggest that compound 15 has a dual mechanism of action, with selective antimicrobial activity against C. acnes and notable anti-inflammatory properties, making it a potential prototype for developing new treatments for acne vulgaris.

10.
Biol Pharm Bull ; 36(12): 1915-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24432378

RESUMO

The naturally occurring pigment, melanin is found in organisms of all phylogenetic kingdoms, including fungi, and exhibits a wide range of biological activities. Our objective was to investigate the effects of melanin extracted from the fungus Aspergillus nidulans on the production of the pro-inflammatory mediators nitric oxide (NO) and tumour necrosis factor-α (TNF-α) in peritoneal macrophages and on the viability of McCoy mouse fibroblasts. The results showed that A. nidulans melanin did not stimulate NO production in macrophages, but it inhibited the NO production in lipopolysaccharide (LPS)-stimulated macrophages by approximately 82%. Similarly, A. nidulans melanin inhibited LPS-stimulated TNF-α production by 52% and showed a slight stimulatory effect on TNF-α production in macrophages. In addition, the toxicity of A. nidulans melanin to McCoy cells was much lesser (IC50=373.5±2.4 µg/mL) than that of known agents such as cisplatin (IC50=41.2 µg/mL). The viability of peritoneal macrophages was greater than 90% at the highest melanin concentration tested (100 µg/mL). Thus, the combination of low cytotoxicity and marked inhibition of TNF-α and NO production suggests that A. nidulans melanin has potential as an anti-inflammatory agent and may be used in the future for development of new drugs with therapeutic utility.


Assuntos
Anti-Inflamatórios/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Melaninas/farmacologia , Óxido Nítrico/antagonistas & inibidores , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Aspergillus nidulans , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Lipopolissacarídeos , Macrófagos Peritoneais/metabolismo , Camundongos
11.
Clin Oral Implants Res ; 24(9): 963-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22697457

RESUMO

OBJECTIVES: To present some immunological aspects of fresh-frozen allogeneic bone grafting for lateral bone augmentation, based on the quantitative evaluation of IL-10, IL-1ß, IFN- γ and TNF- α in patients sera. MATERIAL AND METHODS: Thirty-three partially or totally edentulous patients received fresh-frozen allogeneic bone (AL - 20 patients) or autologous bone onlay block grafts (AT - 13 patients) prior to oral implant placement. Blood samples were collected from each patient at various time-points during a 6 month-period (baseline, 14, 30, 90 and 180 days postoperatively). Quantitative evaluation of IL-10, IL-1ß, IFN- γ and TNF- α was performed by enzyme linked immunosorbent assay (ELISA). RESULTS: For all evaluated markers and at all evaluated periods, inter-group comparisons showed no statistically significant differences between the groups, while the observed values were within normal levels. For AL-treated patients, intra-group evaluation showed statistically significant increase of TNF-α from baseline to 90 (P < 0.001) and 180 (P < 0.01) days, and from 14 to 90 (P < 0.01) and 180 (P < 0.05) days. IFN- γ showed intercalated results, with a decrease from baseline to 14 days (P < 0.05), and increase from 14 to 90 days (P < 0.001) and 180 (P < 0.05) days. No differences between the periods of evaluation were found for the AT group. CONCLUSIONS: AL grafting for lateral bone augmentation, similar to AT grafting, does not seem to challenge the immune system significantly.


Assuntos
Aumento do Rebordo Alveolar/métodos , Biomarcadores/sangue , Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Arcada Edêntula/cirurgia , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-1beta/sangue , Masculino , Pessoa de Meia-Idade , Retalhos Cirúrgicos , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangue
12.
Mycopathologia ; 176(1-2): 57-65, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23686275

RESUMO

Sporotrichosis is a subcutaneous mycosis that is caused by the dimorphic fungus Sporothrix schenckii. This disease generally occurs within the skin and subcutaneous tissues, causing lesions that can spread through adjacent lymphatic vessels and sometimes leading to systemic diseases in immunocompromised patients. Macrophages are crucial for proper immune responses against a variety of pathogens. Furthermore, macrophages can play different roles in response to different microorganisms and forms of activation, and they can be divided into "classic" or "alternatively" activated populations, as also known as M1 and M2 macrophages. M1 cells can lead to tissue injury and contribute to pathogenesis, whereas M2 cells promote angiogenesis, tissue remodeling, and repair. The aim of this study was to investigate the roles of M1 and M2 macrophages in a sporotrichosis model. Toward this end, we performed phenotyping of peritoneal exudate cells and evaluated the concomitant production of several immunomediators, including IL-12, IL-10, TGF-ß, nitric oxide, and arginase-I activity, which were stimulated ex vivo with cell wall peptide-polysaccharide. Our results showed the predominance of the M2 macrophage population, indicated by peaks of arginase-I activity as well as IL-10 and TGF-ß production during the 6th and 8th weeks after infection. These results were consistent with cellular phenotyping that revealed increases in CD206-positive cells over this period. This is the first report of the participation of M2 macrophages in sporotrichosis infections.


Assuntos
Antígenos de Fungos/imunologia , Parede Celular/imunologia , Macrófagos/imunologia , Peptídeos/imunologia , Polissacarídeos/imunologia , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Líquido Ascítico/citologia , Modelos Animais de Doenças , Exsudatos e Transudatos/citologia , Imunofenotipagem , Ativação de Macrófagos , Macrófagos/química , Macrófagos/classificação , Masculino , Camundongos
13.
BMC Complement Altern Med ; 12: 107, 2012 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-22827934

RESUMO

BACKGROUND: Ribosome-inactivating proteins (RIP) have been studied in the search for toxins that could be used as immunotoxins for cancer treatment. Pulchellin, a type 2 RIP, is suggested to induce immune responses that have a role in controlling cancer. METHODS: The percentage of dendritic cells and CD4(+) and CD8(+) T cells in the spleen (flow cytometry), cytokines' release by PECs and splenocytes (ELISA) and nitric oxide production by PECs (Griess assay) were determined from tumor-bearing mice injected intratumorally with 0.1 ml of pulchellin at 0.75 µg/kg of body weight. Statistical analysis was performed by one-way ANOVA with Tukey's post hoc test. RESULTS: Pulchellin-treated mice showed significant immune system activation, characterized by increased release of IFN-γ and Th2 cytokines (IL-4 and IL-10), while IL-6 and TGF-ß levels were decreased. There was also an increase in macrophage's activation, as denoted by the higher percentage of macrophages expressing adhesion and costimulatory molecules (CD54 and CD80, respectively). CONCLUSIONS: Our results suggest that pulchellin is promising as an adjuvant in breast cancer treatment.


Assuntos
Abrus/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Proteínas de Plantas/administração & dosagem , Proteínas Inativadoras de Ribossomos Tipo 2/administração & dosagem , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Citocinas/imunologia , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologia , Células Th2/imunologia
14.
Mycopathologia ; 174(1): 21-30, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22286932

RESUMO

For many fungal diseases, macrophages are the major cell population implicated in host protection, primarily by their ability to eliminate the invading fungal pathogen through phagocytosis. In sporotrichosis, this remains true, because of macrophages' ability to recognize Sporothrix schenckii through specific receptors for some of the fungus' cellular surface constituents. Further confirmation for macrophages' pivotal role in fungal diseases came with the identification of toll-like receptors, and the subsequent numerous associations found between TLR-4 deficiency and host susceptibility to diverse fungal pathogens. Involvement of TLR-4 in immune response against sporotrichosis has been conducted to investigate how TLR-4 signaling could affect inflammatory response development through evaluation of H2O2 production and IL-1ß, IL-6 and TGF-ß release during the course of S. schenckii infection on TLR-4-deficient mice. The results showed that macrophages are largely dependent on TLR-4 for inflammatory activation and that in the absence of TLR-4 signaling, increased TGF-ß release may be one of the contributing factors for the abrogated inflammatory activation of peritoneal exudate cells during mice sporotrichosis.


Assuntos
Macrófagos/imunologia , Macrófagos/microbiologia , Sporothrix/imunologia , Sporothrix/patogenicidade , Esporotricose/imunologia , Esporotricose/patologia , Receptor 4 Toll-Like/deficiência , Animais , Antifúngicos/metabolismo , Antifúngicos/toxicidade , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/toxicidade , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Knockout , Fator de Crescimento Transformador beta/metabolismo
15.
Gerodontology ; 29(2): e275-80, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21284713

RESUMO

OBJECTIVE: To evaluate the effect of water storage time on the cytotoxicity of soft liners. METHODS: Sample discs of soft liners Dentusoft, Dentuflex, Trusoft, Ufi-Gel-P and denture base acrylic resin Lucitone-550 were prepared and divided into four groups: GN: No treatment, G24: Stored in water at 37°C for 24 h; G48: Stored in water at 37°C for 48 h, GHW: Immersed in water at 55°C for 10 min. To analyse the cytotoxic effect, three samples of each group were placed in tubes with Dubelcco's Modified Eagle Mediums and incubated at 37°C for 24 h. During this period, the toxic substances were leached to the culture medium. The cytotoxicity was analysed quantitatively by the incorporation of radioactivity (3)H-thymidine checking the number of viable cells (synthesis of DNA). The data were statistically analysed using two-way anova and Tukey's honestly significant difference tests (α = 0.05). RESULTS: Treatments did not reduce the cytotoxicity effect of the soft liners (p > 0.05). It was found that Ufi-Gel-P had a non-cytotoxic effect, Trusoft had a slightly cytotoxic effect, Dentuflex had a moderated cytotoxic effect, Dentusoft alternated between slightly and non-cytotoxic effect, and Lucitone-550 had non-cytotoxic effect when stored in water for 48 h. CONCLUSION: The effect of water storage and the heat treatment did not reduce the cytotoxicity of the soft liners.


Assuntos
Materiais Dentários/toxicidade , Reembasadores de Dentadura , Resinas Acrílicas/química , Resinas Acrílicas/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados , Materiais Dentários/química , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/toxicidade , Fibroblastos/efeitos dos fármacos , Temperatura Alta , Teste de Materiais , Metilmetacrilatos/química , Metilmetacrilatos/toxicidade , Camundongos , Compostos Radiofarmacêuticos , Elastômeros de Silicone/química , Elastômeros de Silicone/toxicidade , Temperatura , Timidina , Fatores de Tempo , Trítio , Água
16.
Front Cell Infect Microbiol ; 12: 1084526, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36846549

RESUMO

Introduction: Regulatory T cells (Tregs) have been shown to limit the protective immune response against pathogenic species of the fungus Sporothrix spp, the causal agent of sporotrichosis. However, the specific function of Tregs during vaccination against these fungi is known. Methods: We evaluated the effect of Tregs depletion on the immunogenicity of an experimental recombinant anti-Sporothrix vaccine, using the DEREG mice. In this model, only Foxp3(+) Tregs express eGFP and diphtheria toxin (DT) receptors, and transient Tregs depletion is achieved by DT administration. Results: Tregs depletion enhanced the frequency of specific IFNγ+ T cells (Th1 lymphocytes) and cytokine production after either the first or second vaccine dose. However, depletion of Tregs during the second dose caused greater stimulation of specific Th1 lymphocytes than depletion during the first dose. Similarly, the highest production of IgG, IgG1, and IgG2a anti rSsEno antibody was detected after Tregs depletion during boost immunization compared to the other immunized groups. Importantly, vaccine immunogenicity improvement after Tregs depletion also had an impact on the more efficient reduction of fungal load in the skin and liver after the challenge with S. brasiliensis in an experimental infection model. Interestingly, the reduction in fungal load was greatest in the Tregs depleted group during boosting. Discussion: Our results illustrate that Tregs restrict vaccine-induced immune response and their transient depletion could enhance anti-Sporothrix vaccine immunogenicity. Further studies are required to elucidate whether Tregs depletion may be a way to improve the efficacy of vaccination against Sporothrix spp.


Assuntos
Sporothrix , Linfócitos T Reguladores , Animais , Camundongos , Imunização , Vacinação , Fígado
17.
Front Oral Health ; 2: 697428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35048037

RESUMO

This comprehensive review of the literature aimed to investigate the interplay between the oral microbiome, oral cavity conditions, and host immune response in Diabetes mellitus (DM). Moreover, this review also aimed to investigate how DM related risk factors, such as advanced age, hyperglycemia, hyperlipidemia, obesity, hypertension and polycystic ovary syndrome (PCOS), act in promoting or modifying specific mechanisms that could potentially perpetuate both altered systemic and oral conditions. We found that poorly controlled glycemic index may exert a negative effect on the immune system of affected individuals, leading to a deficient immune response or to an exacerbation of the inflammatory response exacerbating DM-related complications. Hyperglycemia induces alterations in the oral microbiome since poor glycemic control is associated with increased levels and frequencies of periodontal pathogens in the subgingival biofilm of individuals with DM. A bidirectional relationship between periodontal diseases and DM has been suggested: DM patients may have an exaggerated inflammatory response, poor repair and bone resorption that aggravates periodontal disease whereas the increased levels of systemic pro-inflammatory mediators found in individuals affected with periodontal disease exacerbates insulin resistance. SARS-CoV-2 infection may represent an aggravating factor for individuals with DM. Individuals with DM tend to have low salivary flow and a high prevalence of xerostomia, but the association between prevalence/experience of dental caries and DM is still unclear. DM has also been associated to the development of lesions in the oral mucosa, especially potentially malignant ones and those associated with fungal infections. Obesity plays an important role in the induction and progression of DM. Co-affected obese and DM individuals tend to present worse oral health conditions. A decrease in HDL and, an increase in triglycerides bloodstream levels seem to be associated with an increase on the load of periodontopathogens on oral cavity. Moreover, DM may increase the likelihood of halitosis. Prevalence of impaired taste perception and impaired smell recognition tend to be greater in DM patients. An important interplay among oral cavity microbiome, DM, obesity and hypertension has been proposed as the reduction of nitrate into nitrite, in addition to contribute to lowering of blood pressure, reduces oxidative stress and increases insulin secretion, being these effects desirable for the control of obesity and DM. Women with PCOS tend to present a distinct oral microbial composition and an elevated systemic response to selective members of this microbial community, but the association between oral microbiome, PCOS are DM is still unknown. The results of the studies presented in this review suggest the interplay among the oral microbiome, oral cavity conditions, host immune response and DM and some of the DM associated risk factors exist. DM individuals need to be encouraged and motivated for an adequate oral health care. In addition, these results show the importance of adopting multidisciplinary management of DM and of strengthening physicians-dentists relationship focusing on both systemic and on oral cavity conditions of DM patients.

18.
J Food Biochem ; 45(1): e13560, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33270240

RESUMO

This study aimed to evaluate the effect of aqueous extract of Paullinia cupana (AEG) against ketoprofen side effects, through biochemical, hematological, and histological parameters. AEG showed antioxidant activity in the DPPH• scavenging (IC50  = 17.00 ± 1.00 µg/ml) and HPLC analysis revealed that this extract is constituted by antioxidants (caffeine, catechins, theobromine, and polyphenols). In vivo experiments in female Wistar rats demonstrated that alterations in urea, creatinine, and uric acid levels promoted (p < .05) by ketoprofen were reversed when AEG was co-administered. Ketoprofen significantly decreased the catalase levels of animal tissues (p < .05), which were restored when AEG was co-administered with the mentioned drug. Histological analysis showed that AEG protected tissues from damages caused by ketoprofen. Moreover, AEG reestablished the number of white blood cells, which had decreased when ketoprofen was administered. In conclusion, this study suggested that the association between ketoprofen and AEG may be an alternative to reduce health damages caused by this drug. PRACTICAL APPLICATIONS: Paullinia cupana, popularly known as guaraná, is commonly consumed as a beverage in Brazil and exhibits pharmacological and beneficial effects to humans. Ketoprofen is an efficacious drug employed in the treatment of inflammatory processes. However, this drug can cause several side effects in humans. Thus, the usage of natural products and plant extracts that can reduce such undesirable effects consists in a valuable strategy to be applied in therapeutic interventions.


Assuntos
Cetoprofeno , Paullinia , Animais , Feminino , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Teobromina
19.
Pharm Biol ; 48(12): 1320-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20839925

RESUMO

CONTEXT: Alchornea triplinervia (Spreng.) Müll. Arg. (Euphorbiaceae) is a tree widespread in many Brazilian states. This plant naturally occurs in different ecosystems including tropical Atlantic forest, Amazon rain forest, moist tropical mixed forest, savanna forest, among others. Local populations traditionally use it in tea form to treat gastric disturbances. OBJECTIVE: The objective of this research was to evaluate the plant A. triplinervia as a potential inhibitor of some macrophage functions involved in the inflammatory process. MATERIALS AND METHODS: The effects of Alchornea triplinervia ethyl acetate fraction (AtF) on hydrogen peroxide (H2O2), nitric oxide (NO) and tumor necrosis factor-α (TNF-α) production in peritoneal macrophages were investigated using phenol red, Griess reagent and a sandwich immunoassay, respectively. RESULTS: AtF chromatographic analyses indicate the presence of flavonoids as majority compounds. The fraction also showed an intense inhibition of H2O2 and NO production. The inhibitory effects of the fraction in H2O2 and NO production ranged from 72.25 ± 4.68 to 69.64 ± 4.21 and from 47.8 ± 8.96 to 76.77 ± 8.11%, respectively in the two tested concentrations, 15.62 and 62.5 µg/mL. TNF-α production was partially inhibited in the tested concentrations and the inhibitory rate was around 18%. DISCUSSION AND CONCLUSION: It is supposed that the elevated biological potential of A. triplinervia is related to the presence of phenolic compounds in the plant leaves. According to the results observed in this study, it is suggested that AtF presents anti-inflammatory activity, supporting the traditional use of A. triplinervia in Brazilian folk medicine.


Assuntos
Anti-Inflamatórios/farmacologia , Euphorbiaceae/química , Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Brasil , Relação Dose-Resposta a Droga , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Peróxido de Hidrogênio/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Medicina Tradicional , Camundongos , Óxido Nítrico/metabolismo , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/administração & dosagem , Folhas de Planta , Fator de Necrose Tumoral alfa/metabolismo
20.
Immunobiology ; 225(5): 151993, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32962813

RESUMO

The role of regulatory T cells (Tregs) on protective immunity in fungal infections, is controversial. Sporotrichosis is an emerging and worldwide-distributed subcutaneous mycosis caused by various related thermodimorphic fungi of the genus Sporothrix. Previously, we showed an elevated percent of Tregs around 21 days post-infection (dpi) in C57BL/6 mice infected with either Sporothrix schenckii or Sporothrix brasiliensis, but the effect of these cells in the ongoing infection was not evaluated. Here, we aim to characterize the role of Foxp3+ Tregs in a subcutaneous S. schenckii infection model. The flow cytometric analyses showed that S. schenckii infection elicited an expansion of a splenic CD4+Foxp3+ population, including a subset of Helioslow+ after ex vivo stimulation with S. schenckii-heat killed yeast. Depletion of Tregs in DEREG mice revealed a reduction of fungal burden in the skin and systemically in liver and kidneys, associated with enhanced Th1 and Th17 responses. Altogether, our results reveal for the first time that Tregs depletion in ongoing S. schenckii infection improves the protective antifungal immunity and these data suggest that Tregs modulation could be explored as a potential therapeutic strategy in sporotrichosis.


Assuntos
Sporothrix , Esporotricose/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Fatores de Transcrição Forkhead/imunologia , Masculino , Camundongos Endogâmicos C57BL , Baço/citologia
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