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1.
Front Cell Infect Microbiol ; 14: 1369226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086605

RESUMO

Objective: The study delved into the epigenetic factors associated with periodontal disease in two lineages of mice, namely C57bl/6 and Balb/c. Its primary objective was to elucidate alterations in the methylome of mice with distinct genetic backgrounds following systemic microbial challenge, employing high-throughput DNA methylation analysis as the investigative tool. Methods: Porphyromonas gingivalis (Pg)was orally administered to induce periodontitis in both Balb/c and C57bl/6 lineage. After euthanasia, genomic DNA from both maxilla and blood were subjected to bisulfite conversion, PCR amplification and genome-wide DNA methylation analysis using the Ovation RRBS Methyl-Seq System coupled with the Illumina Infinium Mouse Methylation BeadChip. Results: Of particular significance was the distinct methylation profile observed within the Pg-induced group of the Balb/c lineage, contrasting with both the control and Pg-induced groups of the C57bl/6 lineage. Utilizing rigorous filtering criteria, we successfully identified a substantial number of differentially methylated regions (DMRs) across various tissues and comparison groups, shedding light on the prevailing hypermethylation in non-induced cohorts and hypomethylation in induced groups. The comparison between blood and maxilla samples underscored the unique methylation patterns specific to the jaw tissue. Our comprehensive methylome analysis further unveiled statistically significant disparities, particularly within promoter regions, in several comparison groups. Conclusion: The differential DNA methylation patterns observed between C57bl/6 and Balb/c mouse lines suggest that epigenetic factors contribute to the variations in disease susceptibility. The identified differentially methylated regions associated with immune regulation and inflammatory response provide potential targets for further investigation. These findings emphasize the importance of considering epigenetic mechanisms in the development and progression of periodontitis.


Assuntos
Metilação de DNA , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Porphyromonas gingivalis , Animais , Porphyromonas gingivalis/genética , Camundongos , Periodontite/microbiologia , Epigênese Genética , Doenças Periodontais/microbiologia , Suscetibilidade a Doenças , Infecções por Bacteroidaceae/microbiologia , Epigenoma
2.
Vaccine ; 42(21): 126178, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39096765

RESUMO

American Tegumentary Leishmaniasis (ATL) is a disease of high severity and incidence in Brazil, in addition to being a worldwide concern in public health. Leishmania amazonensis is one of the etiological agents of ATL, and the inefficiency of control measures, associated with the high toxicity of the treatment and the lack of effective immunoprophylactic strategies, makes the development of vaccines indispensable and imminent. In this light, the present study proposes to elaborate a chimeric protein (rChiP), based on the fusion of multiple epitopes of CD4+/CD8+ T cells, identified in the immunoproteome of the parasites L. amazonensis and L. braziliensis. The designed chimeric protein was tested in the L. amazonensis murine model of infection using the following formulations: 25 µg of the rChiP in saline (rChiP group) and 25 µg of the rChiP plus 25 µg of MPLA-PHAD® (rChiP+MPLA group). After completing immunization, CD4+ and CD8+ T cells, stimulated with SLa-Antigen or rChiP, showed an increased production of nitric oxide and intracytoplasmic pro-inflammatory cytokines, in addition to the generation of central and effector memory T cells. rChiP and rChiP+MPLA formulations were able to promote an effective protection against L. amazonensis infection determined by a reduction in the development of skin lesions and lower parasitic burden. Reduction in the development of skin lesions and lower parasitic burden in the vaccinated groups were associated with an increase of nitrite, CD4+/CD8+IFN-γ+TNF-α+ and CD4+/CD8+CD44highCD62Lhigh/low T cells, IgGTotal, IgG2a, and lower rates of IgG1 and CD4+/CD8+IL-10+. This data suggests that proposed formulations could be considered potential tools to prevent ATL.


Assuntos
Adjuvantes Imunológicos , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Memória Imunológica , Vacinas contra Leishmaniose , Leishmaniose Cutânea , Animais , Leishmaniose Cutânea/prevenção & controle , Leishmaniose Cutânea/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD4-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Camundongos , Vacinas contra Leishmaniose/imunologia , Feminino , Adjuvantes Imunológicos/administração & dosagem , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/genética , Leishmania braziliensis/imunologia , Lipídeo A/análogos & derivados , Lipídeo A/imunologia , Anticorpos Antiprotozoários/imunologia , Citocinas/metabolismo , Citocinas/imunologia , Modelos Animais de Doenças , Antígenos de Protozoários/imunologia
3.
Int J Mol Sci ; 25(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39126001

RESUMO

Breast cancer is the most diagnosed type of cancer worldwide and the second cause of death in women. Triple-negative breast cancer (TNBC) is the most aggressive, and due to the lack of specific targets, it is considered the most challenging subtype to treat and the subtype with the worst prognosis. The present study aims to determine the antitumor effect of beta-D-glucose-reduced silver nanoparticles (AgNPs-G) in a murine model of TNBC, as well as to study its effect on the tumor microenvironment. In an airbag model with 4T1 tumor cell implantation, the administration of AgNPs-G or doxorubicin showed antitumoral activity. Using immunohistochemistry it was demonstrated that treatment with AgNPs-G decreased the expression of PCNA, IDO, and GAL-3 and increased the expression of Caspase-3. In the tumor microenvironment, the treatment increased the percentage of memory T cells and innate effector cells and decreased CD4+ cells and regulatory T cells. There was also an increase in the levels of TNF-α, IFN-γ, and IL-6, while TNF-α was increased in serum. In conclusion, we suggest that AgNPs-G treatment has an antitumor effect that is demonstrated by its ability to remodel the tumor microenvironment in mice with TNBC.


Assuntos
Glucose , Nanopartículas Metálicas , Prata , Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Prata/química , Nanopartículas Metálicas/química , Feminino , Camundongos , Glucose/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Doxorrubicina/farmacologia , Humanos
4.
Int J Mol Sci ; 25(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39125769

RESUMO

A T-cell-independent (TI) pathway activated by microbiota results in the generation of low-affinity homeostatic IgA with a critical role in intestinal homeostasis. Moderate aerobic exercise (MAE) provides a beneficial impact on intestinal immunity, but the action of MAE on TI-IgA generation under senescence conditions is unknown. This study aimed to determine the effects of long-term MAE on TI-IgA production in young (3 month old) BALB/c mice exercised until adulthood (6 months) or aging (24 months). Lamina propria (LP) from the small intestine was obtained to determine B cell and plasma cell sub-populations by flow cytometry and molecular factors related to class switch recombination [Thymic Stromal Lymphopoietin (TSLP), A Proliferation-Inducing Ligand (APRIL), B Cell Activating Factor (BAFF), inducible nitric oxide synthase (iNOS), and retinal dehydrogenase (RDH)] and the synthesis of IgA [α-chain, interleukin (IL)-6, IL-21, and Growth Factor-ß (TGF-ß)]; and epithelial cells evaluated IgA transitosis [polymeric immunoglobulin receptor (pIgR), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), IL-4] by the RT-qPCR technique. The results were compared with data obtained from sedentary age-matched mice. Statistical analysis was computed with ANOVA, and p < 0.05 was considered to be a statistically significant difference. Under senescence conditions, MAE promoted the B cell and IgA+ B cells and APRIL, which may improve the intestinal response and ameliorate the inflammatory environment associated presumably with the downmodulation of pro-inflammatory mediators involved in the upmodulation of pIgR expression. Data suggested that MAE improved IgA and downmodulate the cytokine pro-inflammatory expression favoring homeostatic conditions in aging.


Assuntos
Envelhecimento , Homeostase , Imunoglobulina A , Camundongos Endogâmicos BALB C , Condicionamento Físico Animal , Animais , Imunoglobulina A/metabolismo , Imunoglobulina A/imunologia , Camundongos , Envelhecimento/imunologia , Citocinas/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Fator Ativador de Células B/metabolismo , Fator Ativador de Células B/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Masculino , Plasmócitos/imunologia , Plasmócitos/metabolismo , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
5.
Virus Genes ; 60(5): 475-487, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39102085

RESUMO

DENV infection outcomes depend on the host's variable expression of immune receptors and mediators, leading to either resolution or exacerbation. While the NS3 protein is known to induce robust immune responses, the specific impact of its protease region epitopes remains unclear. This study investigated the effect of recombinant NS3 protease region proteins from all four DENV serotypes on splenocyte activation in BALB/c mice (n = 5/group). Mice were immunized with each protein, and their splenocytes were subsequently stimulated with homologous antigens. We measured the expression of costimulatory molecules (CD28, CD80, CD86, CD152) by flow cytometry, along with IL-2 production, CD25 expression, and examined the antigen-specific activation of CD4 + and CD8 + T cells. Additionally, the expression of IL-1, IL-10, and TGF-ß1 in splenocytes from immunized animals was assessed. Apoptosis was evaluated using Annexin V/PI staining and DNA fragmentation analysis. Stimulation of splenocytes from immunized mice triggered apoptosis (phosphatidylserine exposure and caspase 3/7 activation) and increased costimulatory molecule expression, particularly CD152. Low IL-2 production and low CD25 expression, as well as sustained expression of the IL-10 gene. These results suggest that these molecules might be involved in mechanisms by which the NS3 protein contributes to viral persistence and disease pathogenesis.


Assuntos
Apoptose , Antígeno CTLA-4 , Vírus da Dengue , Camundongos Endogâmicos BALB C , Baço , Proteínas não Estruturais Virais , Animais , Camundongos , Baço/imunologia , Baço/virologia , Vírus da Dengue/imunologia , Vírus da Dengue/genética , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Imunização , Dengue/imunologia , Dengue/virologia , Citocinas/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia
6.
Exp Parasitol ; 265: 108808, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094996

RESUMO

This study aimed to develop microemulsions (MEs) containing α-bisabolol for the topical treatment of cutaneous leishmaniasis (CL). Initially, pseudoternary phase diagrams were developed using α-bisabolol as the oil phase, Eumulgin® CO 40 as the surfactant, Polymol® HE as the co-surfactant, and distilled water as the aqueous phase. Two transparent liquid systems (TLS) containing 5% of α-bisabolol were selected and characterized (F5E25 and F5EP25). Next, skin permeation and retention assays were performed using Franz cells. The interaction of the formulation with the stratum corneum (SC) was evaluated using the FTIR technique. The cytotoxicity was evaluated in murine peritoneal macrophages. Finally, the antileishmanial activity of microemulsions was determined in promastigotes and amastigotes of L. amazonensis (strain MHOM/BR/77/LTB 0016). As a result, the selected formulations showed isotropy, nanometric size (below 25 nm), Newtonian behavior and pH ranging from 6.5 to 6.9. The MEs achieved a 2.5-fold increase in the flux and skin-permeated amount of α-bisabolol. ATR-FTIR results showed that microemulsions promoted fluidization and extraction of lipids and proteins of the stratum corneum, increasing the diffusion coefficient and partition coefficient of the drug in the skin. Additionally, F5E25 and F5EP25 showed higher activity against promastigotes (IC50 13.27 and 18.29, respectively) compared to unencapsulated α-bisabolol (IC50 53.8). Furthermore, F5E25 and F5EP25 also showed antileishmanial activity against intracellular amastigotes of L. amazonensis, with IC50 50 times lower than free α-bisabolol and high selectivity index (up to 15). Therefore, the systems obtained are favorable to topical administration, with significant antileishmanial activity against L. amazonensis promastigotes and amastigotes, being a promising system for future in vivo trials.


Assuntos
Emulsões , Macrófagos Peritoneais , Sesquiterpenos Monocíclicos , Sesquiterpenos , Pele , Animais , Sesquiterpenos Monocíclicos/farmacologia , Sesquiterpenos Monocíclicos/química , Emulsões/química , Camundongos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Pele/parasitologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Espectroscopia de Infravermelho com Transformada de Fourier , Absorção Cutânea/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Feminino , Leishmania/efeitos dos fármacos , Tensoativos/farmacologia , Tensoativos/química , Antiprotozoários/farmacologia , Antiprotozoários/química
7.
Vaccine ; 42(21): 126141, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39033080

RESUMO

Amblyomma sculptum is widely distributed in Brazil and is the main vector of Rickettsia rickettsii, the causative agent of the Brazilian spotted fever (BSF). Tick gut proteins play an essential role in blood feeding, digestion, and protection of gut epithelium. Therefore, many of these were investigated as potential vaccine targets for tick-control strategies. The present study aimed to select transcripts corresponding to putative immunogenic proteins in the A. sculptum gut epithelial membrane, produce recombinant proteins and evaluate them as antigens against A. sculptum infestations. Three gut proteins - AsMucin, AsAPP, and AsLAMP - and a chimeric protein (rAsChimera) based on 22 peptides containing putative B cell epitopes from seven different gut proteins were evaluated as anti-A. sculptum antigens. Mice immunizations revealed that all recombinant targets elicited humoral response with significantly increased IgG levels compared to controls. For rAsChimera, IgG levels remained significantly higher than controls up to 75 days after the end of the immunization. Challenge trials revealed that vaccination with the chimeric protein was the most effective against A. sculptum, inducing 100 % nymph mortality and reaching 80.8 % efficacy against females. The other three proteins did not induce relevant protection, as AsAPP had only 26.6 % efficacy, whereas AsMucin and AsLAMP induced no protection. These data indicate that targeting gut protein immunogenic regions may be an effective strategy for a vaccine formulation againstA. sculptum.


Assuntos
Amblyomma , Animais , Camundongos , Feminino , Amblyomma/imunologia , Imunização/métodos , Proteínas de Membrana/imunologia , Proteínas de Membrana/genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/imunologia , Rickettsia rickettsii/imunologia , Brasil , Masculino , Camundongos Endogâmicos BALB C , Antígenos/imunologia
8.
Int J Mol Sci ; 25(14)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39063180

RESUMO

T-cell malignancies, including T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL), present significant challenges to treatment due to their aggressive nature and chemoresistance. Chemotherapies remain a mainstay for their management, but the aggressiveness of these cancers and their associated toxicities pose limitations. Immunepotent CRP (ICRP), a bovine dialyzable leukocyte extract, has shown promise in inducing cytotoxicity against various cancer types, including hematological cancers. In this study, we investigated the combined effect of ICRP with a panel of chemotherapies on cell line models of T-ALL and T-LBL (CEM and L5178Y-R cells, respectively) and its impact on immune system cells (peripheral blood mononuclear cells, splenic and bone marrow cells). Our findings demonstrate that combining ICRP with chemotherapies enhances cytotoxicity against tumoral T-cell lymphoblasts. ICRP + Cyclophosphamide (CTX) cytotoxicity is induced through a caspase-, reactive oxygen species (ROS)-, and calcium-dependent mechanism involving the loss of mitochondrial membrane potential, an increase in ROS production, and caspase activation. Low doses of ICRP in combination with CTX spare non-tumoral immune cells, overcome the bone marrow-induced resistance to CTX cell death, and improves the CTX antitumor effect in vivo in syngeneic Balb/c mice challenged with L5178Y-R. This led to a reduction in tumor volume and a decrease in Ki-67 proliferation marker expression and the granulocyte/lymphocyte ratio. These results set the basis for further research into the clinical application of ICRP in combination with chemotherapeutic regimens for improving outcomes in T-cell malignancies.


Assuntos
Ciclofosfamida , Espécies Reativas de Oxigênio , Animais , Camundongos , Humanos , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Ciclofosfamida/farmacologia , Sinergismo Farmacológico , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Apoptose/efeitos dos fármacos , Bovinos , Morte Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Camundongos Endogâmicos BALB C , Proliferação de Células/efeitos dos fármacos
9.
PLoS One ; 19(7): e0301664, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985719

RESUMO

Influenza viruses constitute a major threat to human health globally. The viral surface glycoprotein hemagglutinin (HA) is the immunodominant antigen, contains the site for binding to the cellular receptor (RBS), and it is the major target of neutralizing antibody responses post-infection. We developed llama-derived single chain antibody fragments (VHHs) specific for type A influenza virus. Four VHHs were identified and further characterized. VHH D81 bound residues in the proximity of the C-terminal region of HA1 of H1 and H5 subtypes, and showed weak neutralizing activity, whereas VHH B33 bound residues in the proximity of the N-terminal region of the HA's stem domain (HA2) of H1, H5, and H9 subtypes, and showed no neutralizing activity. Of most relevance, VHHs E13 and G41 recognized highly conserved conformational epitopes on the H1 HA's globular domain (HA1) and showed high virus neutralizing activity (ranging between 0.94 to 0.01µM), when tested against several human H1N1 isolates. Additionally, E13 displayed abrogated virus replication of a panel of H1N1 strains spanning over 80 years of antigenic drift and isolated from human, avian, and swine origin. Interestingly, E13 conferred protection in vivo at a dose as low as 0.05 mg/kg. Mice treated with E13 intranasally resulted in undetectable virus challenge loads in the lungs at day 4 post-challenge. The transfer of sterilizing pan-H1 immunity, by a dose in the range of micrograms given intranasally, is of major significance for a monomeric VHH and supports the further development of E13 as an immunotherapeutic agent for the mitigation of influenza infections.


Assuntos
Anticorpos Neutralizantes , Camelídeos Americanos , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vírus da Influenza A Subtipo H1N1 , Infecções por Orthomyxoviridae , Anticorpos de Domínio Único , Animais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Anticorpos de Domínio Único/imunologia , Anticorpos Neutralizantes/imunologia , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Camelídeos Americanos/imunologia , Anticorpos Antivirais/imunologia , Feminino , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Epitopos/imunologia , Cães , Camundongos Endogâmicos BALB C
10.
PLoS One ; 19(7): e0307307, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39024223

RESUMO

Tuberculosis (TB) is an infectious, chronic, and progressive disease occurring globally. Human TB is caused mainly by Mycobacterium tuberculosis (M. tuberculosis), while the main causative agent of bovine TB is Mycobacterium bovis (M. bovis). The latter is one of the most important cattle pathogens and is considered the main cause of zoonotic TB worldwide. The mechanisms responsible for tissue damage (necrosis) during post-primary TB remain elusive. Recently, IL-17A was reported to be important for protection against M. tuberculosis infection, but it is also related to the production of an intense inflammatory response associated with necrosis. We used two M. bovis isolates with different levels of virulence and high IL-17A production to study this important cytokine's contrasting functions in a BALB/c mouse model of pulmonary TB. In the first part of the study, the gene expression kinetics and cellular sources of IL-17A were determined by real time PCR and immunohistochemistry respectively. Non-infected lungs showed low production of IL-17A, particularly by the bronchial epithelium, while lungs infected with the low-virulence 534 strain showed high IL-17A expression on Day 3 post-infection, followed by a decrease in expression in the early stage of the infection and another increase during late infection, on Day 60, when very low bacillary burdens were found. In contrast, infection with the highly virulent strain 04-303 induced a peak of IL-17A expression on Day 14 of infection, 1 week before extensive pulmonary necrosis was seen, being lymphocytes and macrophages the most important sources. In the second part of the study, the contribution of IL-17A to immune protection and pulmonary necrosis was evaluated by suppressing IL-17A via the administration of specific blocking antibodies. Infection with M. bovis strain 534 and treatment with IL-17A neutralizing antibodies did not affect mouse survival but produced a significant increase in bacillary load and a non-significant decrease in inflammatory infiltrate and granuloma area. In contrast, mice infected with the highly virulent 04-303 strain and treated with IL-17A blocking antibodies showed a significant decrease in survival, an increase in bacillary loads on Day 24 post-infection, and significantly more and earlier necrosis. Our results suggest that high expression of IL-17A is more related to protection than necrosis in a mouse model of pulmonary TB induced by M. bovis strains.


Assuntos
Interleucina-17 , Camundongos Endogâmicos BALB C , Mycobacterium bovis , Tuberculose Pulmonar , Interleucina-17/metabolismo , Interleucina-17/imunologia , Animais , Mycobacterium bovis/patogenicidade , Mycobacterium bovis/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia , Camundongos , Virulência , Pulmão/microbiologia , Pulmão/patologia , Pulmão/imunologia , Feminino , Bovinos
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