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1.
Sci Rep ; 10(1): 15994, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994497

RESUMO

Ticks are important vectors that transmit several pathogens including human anaplasmosis agent, Anaplasma phagocytophilum. This bacterium is an obligate intracellular rickettsial pathogen. An infected reservoir animal host is often required for maintenance of this bacterial colony and as a source for blood to perform needle inoculations in naïve animals for tick feeding studies. In this study, we report an efficient microinjection method to generate A. phagocytophilum-infected ticks in laboratory conditions. The dense-core (DC) form of A. phagocytophilum was isolated from in vitro cultures and injected into the anal pore of unfed uninfected Ixodes scapularis nymphal ticks. These ticks successfully transmitted A. phagocytophilum to the murine host. The bacterial loads were detected in murine blood, spleen, and liver tissues. In addition, larval ticks successfully acquired A. phagocytophilum from mice that were previously infected by feeding with DC-microinjected nymphal ticks. Transstadial transmission of A. phagocytophilum from larvae to nymphal stage was also evident in these ticks. Taken together, our study provides a timely, rapid, and an efficient method not only to generate A. phagocytophilum-infected ticks but also provides a tool to understand acquisition and transmission dynamics of this bacterium and perhaps other rickettsial pathogens from medically important vectors.


Assuntos
Anaplasma phagocytophilum/fisiologia , Anaplasmose/transmissão , Ixodes/microbiologia , Técnicas Microbiológicas/métodos , Microinjeções/métodos , Animais , Vetores Aracnídeos/microbiologia , Carga Bacteriana , Sangue/microbiologia , Feminino , Células HL-60 , Humanos , Ixodes/crescimento & desenvolvimento , Fígado/microbiologia , Camundongos , Ninfa/microbiologia , Baço/microbiologia
2.
PLoS One ; 15(9): e0239668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970762

RESUMO

We developed an approach for substantial attenuation of Mycobacterium tuberculosis by prolonged culturing under gradually acidifying conditions. Bacteria subjected to acidification lost the capacity to form colonies on solid media, but readily resuscitated their growth in the murine host, providing a useful model to study in vivo development of infection mimicking latent and reactivation tuberculosis (TB) in humans. Here we characterize biomarkers of lung pathology and immune responses triggered by such attenuated bacteria in genetically TB-susceptible and resistant mice. In susceptible I/St mice, CFU counts in lungs and spleens were ~1.5-log higher than in resistant B6 mice, accompanied by diffuse pneumonia and excessive lung infiltration with highly activated CD44+CD62L- T-lymphocytes resulting in death between months 7-9 post challenge. B6 mice were characterized by development of local inflammatory foci, higher production of pro-inflammatory IL-6 and IL-11 cytokines and a more balanced T-cell activation in their lungs. CFU counts remained stable in B6 mice during the whole 18-mo observation period, and all mice survived. Thus, we established a mouse model of fatal reactivation TB vs. indefinite mycobacterial possession after identical challenge and characterized the features of immune responses in the lung tissue underlining these polar phenotypes.


Assuntos
Predisposição Genética para Doença , Interleucinas/metabolismo , Pulmão/imunologia , Ativação Linfocitária , Tuberculose Pulmonar/imunologia , Tuberculose Esplênica/imunologia , Animais , Carga Bacteriana , Células Cultivadas , Feminino , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Interleucinas/genética , Selectina L/genética , Selectina L/metabolismo , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/patogenicidade , Baço/imunologia , Baço/microbiologia , Linfócitos T/imunologia , Tuberculose Pulmonar/genética , Tuberculose Esplênica/genética
3.
Mol Ecol ; 29(17): 3167-3169, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32745298

RESUMO

What happens when two emergent diseases infect the same host? In a From the Cover article in this issue of Molecular Ecology, McDonald et al. (2020) compare transcriptomic responses to co-infection by the two chytrid fungi in the skin, liver and spleen of Eastern newts (Notophthalmus viridescens). Novel molecular tools, such as high-throughput DNA sequencing for genome discovery and transcriptomics, have revolutionized our understanding of host-pathogen interactions and disease ecology (Güimil et al. 2005; Rosenblum et al. 2012). For example, epidemiologists are using genomic data to track the spread of the emergent SARS-CoV-2 in real time, both locally and globally. RNA sequencing (RNA-Seq) is routinely employed to study response to disease in humans, improving disease diagnostics, profiling and development of intervention strategies. Transcriptomic profiles may be particularly informative for emergent diseases, whose pathologies and effect on host phenotype are poorly known. Fungal pathogens increasingly threaten a variety of wild and domesticated organisms (Fisher et al. 2012), and two chytrid fungi attacking amphibians are causing one of the worst losses of vertebrate biodiversity ever recorded (Scheele et al. 2019).


Assuntos
Quitridiomicetos/imunologia , Micoses/veterinária , Salamandridae/imunologia , Animais , Coinfecção/imunologia , Perfilação da Expressão Gênica , Humanos , Fígado/microbiologia , Micoses/imunologia , Micoses/microbiologia , Salamandridae/genética , Salamandridae/microbiologia , Pele/microbiologia , Baço/microbiologia , Transcriptoma/genética
4.
Am J Trop Med Hyg ; 103(3): 970-975, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32602433

RESUMO

Nine criteria regarding the infectious agent, mode of transmission, portal of entry, route of spread, target organs, target cells, pathologic lesions, incubation period, and modifiable spectrum of disease and outcomes appropriate to the intended experimental purpose are described. To provide context for each criterion, mouse models of two vector-borne zoonotic infectious diseases, scrub typhus and dengue, are summarized. Application of the criteria indicates that intravenous inoculation of Orientia tsutsugamushi into inbred mice is the best current model for life-threatening scrub typhus, and intradermal inoculation accurately models sublethal human scrub typhus, whereas the immunocompromised mouse models of dengue provide disease outcomes most closely associated with human dengue. In addition to addressing basic questions of immune and pathogenic mechanisms, mouse models are useful for preclinical testing of experimental vaccines and therapeutics. The nine criteria serve as guidelines to evaluate and compare models of vector-borne infectious diseases.


Assuntos
Vírus da Dengue/imunologia , Dengue/imunologia , Modelos Animais de Doenças , Hospedeiro Imunocomprometido , Orientia tsutsugamushi/imunologia , Tifo por Ácaros/imunologia , Animais , Dengue/patologia , Dengue/virologia , Vírus da Dengue/patogenicidade , Humanos , Período de Incubação de Doenças Infecciosas , Injeções Intradérmicas , Injeções Intravenosas , Fígado/microbiologia , Fígado/virologia , Tecido Linfoide/microbiologia , Tecido Linfoide/virologia , Camundongos , Camundongos Knockout , Orientia tsutsugamushi/patogenicidade , Tifo por Ácaros/microbiologia , Tifo por Ácaros/patologia , Baço/microbiologia , Baço/virologia
5.
Sci Rep ; 10(1): 9421, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32523093

RESUMO

Although shedding of zoonotic brucellae in milk has been demonstrated in natural hosts, these data are still missing for the standard murine infection model. We therefore analysed shedding kinetics and the niche of B. melitensis in murine milk. Pregnant Balb/cByJ mice were intraperitoneally infected with 105 CFU of the 16 M reference strain, a 16 M mCherry mutant or a human isolate. Milk was collected over the course of lactation, and subjected to culture and immunofluorescence assays. Bacteria were also quantified in spleen and mammary glands of maternal mice and in spleen of the litter. The shedding of the three strains did not differ significantly (p = 0.301), ranging from log10 1.5 to 4.04 CFU/ml. A total of 73% of the mice excreted B. melitensis into the milk with peak values at mid-lactation; up to 30 bacteria/cell were found in macrophages and neutrophils. While the bacterial counts in the spleen of lactating females confirmed a well-established infection, only 50% of the pups harboured brucellae in their spleen, including the spleen of an uninfected pup fed by an infected foster mother. In conclusion, the murine model of infection may contribute to a better understanding of the zoonotic transmission of brucellosis.


Assuntos
Brucella melitensis/fisiologia , Brucelose/microbiologia , Macrófagos/microbiologia , Leite/microbiologia , Animais , Modelos Animais de Doenças , Feminino , Lactação/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Baço/microbiologia , Virulência/fisiologia
6.
PLoS One ; 15(6): e0234731, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544181

RESUMO

Airborne fungi are associated with upper and lower airway inflammatory diseases. Alternaria is commonly found in nasal secretions and induces the production of chemical mediators from sinonasal mucosa. This study aimed to establish an Alternaria-induced chronic rhinosinusitis (CRS) mouse model and determine the influence of host allergic background on the immunopathological characteristics of CRS. BALB/c mice were used for establishing the CRS model. Alternaria was intranasally instilled for 8 or 16 weeks with or without ovalbumin (OVA) presensitization. Total serum IgE and Alternaria-specific IgE levels were measured by enzyme-linked immunosorbent assay (ELISA). Interleukin (IL)-4, IL-10, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α levels in nasal lavage fluid (NLF) and splenocytes were measured by ELISA and their mRNAs and levels of associated transcription factors in sinonasal mucosa were determined with quantitative reverse-transcriptase polymerase chain reaction (RT-PCR). Hematoxylin-eosin staining and periodic acid-Schiff staining were performed to evaluate histological changes. Total serum IgE was increased in both allergic and non-allergic CRS. IL-4 was strongly expressed in NLF in both allergic and non-allergic CRS at 16 weeks and not only eosinophils but also neutrophils were increased in NLF of non-allergic CRS mice. The levels of Th1, Th2, and Treg cytokines and transcription factor mRNAs were significantly increased in sinonasal mucosa of non-allergic CRS mice. Both inflammatory cell infiltration and goblet cell hyperplasia were increased in CRS mice. Repeated intranasal instillation of Alternaria results in sinonasal inflammation with inflammatory cell infiltration. The sinonasal mucosal immune responses against Alternaria were shown to differ depending on the host allergic background.


Assuntos
Alternaria/patogenicidade , Rinite/patologia , Sinusite/patologia , Alternaria/imunologia , Animais , Doença Crônica , Modelos Animais de Doenças , Feminino , Imunoglobulina E/sangue , Interleucina-10/análise , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-4/análise , Interleucina-4/genética , Interleucina-4/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Líquido da Lavagem Nasal/química , Mucosa Nasal/metabolismo , Mucosa Nasal/patologia , RNA Mensageiro/metabolismo , Rinite/imunologia , Sinusite/imunologia , Baço/metabolismo , Baço/microbiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
Avian Dis ; 64(1): 7-15, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32267120

RESUMO

Salmonella enterica serovar Enteritidis is the leading cause of salmonellosis in people, and modeling of infections in chickens is used to identify intervention strategies. A review of 80 manuscripts encompassing 119 experiments indicated that the mean dose of infection was 108 CFU per bird. Experiments of less than 106 CFU were primarily conducted in immature birds. To address a lack of information on the impact of low dosages on the hen at lay, two experiments were conducted in triplicate. Experiment A addressed issues associated with vaccination; thus, hens were infected intramuscularly at 103, 105, and 107 CFU. For Experiment B, which was focused more on colonization and invasion, hens were infected orally with 5 × 103 CFU with 4 strains from different genomic clades. Samples from liver, spleen, ovarian pedicle, and paired ceca in both experiments were cultured 5, 6, 7, and 8 days postinfection. Eggshell microbiome taxa were assessed in Experiment B. Results indicated that dosages of 103 CFU in both experiments produced enough positive samples to be used within models. The intramuscular route resulted in approximately twice as many positive samples as the oral route. The kinetics of infection appeared to differ between low and high dosages suggestive of a J-curve response. These results could impact risk assessments if the hen at lay has a nonlinear response to infectious dose.


Assuntos
Galinhas , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/fisiologia , Animais , Ceco/microbiologia , Feminino , Genoma Bacteriano , Fígado/microbiologia , Ovário/microbiologia , Reprodução , Salmonella enteritidis/genética , Baço/microbiologia
8.
Fish Shellfish Immunol ; 100: 41-48, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32142874

RESUMO

Vitamin D3 (VD3) has been shown to modulate the innate immune response in mammals but this has been rarely reported in fish. The current study found that increasing dietary VD3 content can reduce the density of yellow to dark brown pigmented macrophage aggregates (PMAs) in the spleens of yellow catfish infected with Edwardsiella ictaluri. The results of next-generation sequencing showed that a high dose of dietary VD3 (16,600 IU/kg) mainly affected the splenic immune response during Edwardsiella ictaluri infection via negative regulation of 'NF-κΒ transcription factor activity', 'NIK/NF-κΒ signaling' and the 'i-kappab kinase/NF-κΒ signaling' pathways. Follow-up qPCR showed that dietary VD3 increased the expression of NF-κΒ inhibitor iκb-α, decreased the expression of nf-κb p65, il-6, il1-ß and tnf-α, and down-regulated the expression of nik, ikks and nf-κb p52 in the NIK/NF-kappaB signaling pathway. The above results indicate that dietary VD3 can modulate the splenic innate immune response of yellow catfish after Edwardsiella ictaluri infection by inhibiting the NF-κB activation signaling pathways.


Assuntos
Peixes-Gato/imunologia , Colecalciferol/administração & dosagem , Infecções por Enterobacteriaceae/veterinária , Imunidade Inata , Baço/imunologia , Ração Animal , Animais , Peixes-Gato/genética , Suplementos Nutricionais , Edwardsiella ictaluri , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/prevenção & controle , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/prevenção & controle , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Transdução de Sinais , Baço/microbiologia
9.
Fish Shellfish Immunol ; 100: 407-417, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32200071

RESUMO

Transferrin receptors (TfRs) play an essential role in iron-withholding strategy, and are involved in immune response against bacterial infection. In this study, the transferrin receptor 1 (OnTfR1) and transferrin receptor 2 (OnTfR2) genes are identified and characterized in Nile tilapia (Oreochromis niloticus). The open reading frames of OnTfR1 and OnTfR2 are 2220 and 2343 bp of nucleotide sequence, encoding 739 and 780 amino acids, respectively. The deduced proteins of OnTfR1 and OnTfR2 are highly homologous to those of other species, containing three conserved TfR superfamily domains (PA TfR domain, M28 TfR domain and TfR dimer domain). Expression analyses of OnTfRs in the healthy tilapia reveal that the OnTfR1 and OnTfR2 transcripts are the most abundant in the liver. The in vivo studies show that the expressions of OnTfRs are significantly up-regulate in liver and spleen, following infections of Streptococcus agalactiae and Aeromonas hydrophila. In addition, the in vitro studies reveal that the up-regulations of OnTfR expressions are also significant in monocytes/macrophages and hepatocytes upon the stimulations of S. agalactiae and A. hydrophila. Moreover, the iron ion (Fe3+) could significantly increase the expressions of OnTfRs in monocytes/macrophages and hepatocytes. Taken together, the present study indicates that OnTfRs may be involved in host defense against bacterial infection and possess the function of combining or transporting iron ions in Nile tilapia.


Assuntos
Ciclídeos/genética , Resistência à Doença , Proteínas de Peixes/genética , Infecções por Bactérias Gram-Negativas/veterinária , Ferro/metabolismo , Receptores da Transferrina/genética , Animais , Ciclídeos/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Regulação da Expressão Gênica , Bactérias Gram-Negativas/patogenicidade , Infecções por Bactérias Gram-Negativas/imunologia , Interações Hospedeiro-Patógeno , Imunidade Inata , Íons/metabolismo , Fígado/imunologia , Fígado/microbiologia , Macrófagos/imunologia , Receptores da Transferrina/classificação , Receptores da Transferrina/imunologia , Baço/imunologia , Baço/microbiologia
10.
Eur J Immunol ; 50(5): 736-747, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32113187

RESUMO

Prolonged therapy, drug toxicity, noncompliance, immune suppression, and alarming emergence of drug resistance necessitate the search for therapeutic vaccine strategies for tuberculosis (TB). Such strategies ought to elicit not only IFN-γ, but polyfunctional response including TNF-α, which is essential for protective granuloma formation. Here, we investigated the impact of PD-1 inhibition in facilitating protective polyfunctional T cells (PFTs), bacillary clearance, and disease resolution. We have observed PD-1 inhibition preferentially rescued the suppressed PFTs in active tuberculosis patients. In addition, polyfunctional cytokine milieu favored apoptosis of infected MDMs over necrosis with markedly reduced bacillary growth (≪CFU) in our in vitro monocyte-derived macrophages (MDMs) infection model. Furthermore, the animal study revealed a significant decline in the bacterial burden in the lungs and spleen of infected mice after in vivo administration of α-PD-1 along with antitubercular treatment. Our findings suggest that rescuing polyfunctional immune response by PD-1 inhibition works synergistically with antituberculosis chemotherapy to confer improved control over bacillary growth and dissemination. In summary, our data strongly indicate the therapeutic potential of α-PD-1 as adjunct immunotherapy that can rejuvenate suppressed host immunity and enhance the efficacy of candidate therapeutic vaccine(s).


Assuntos
Anticorpos/farmacologia , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Tuberculose Pulmonar/tratamento farmacológico , Adolescente , Adulto , Animais , Carga Bacteriana/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Terapia Combinada/métodos , Feminino , Humanos , Interferon gama/genética , Interferon gama/imunologia , Isoniazida/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Cultura Primária de Células , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Rifampina/farmacologia , Baço/efeitos dos fármacos , Baço/imunologia , Baço/microbiologia , Resultado do Tratamento , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
11.
Can J Microbiol ; 66(5): 351-358, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32040345

RESUMO

Iron is a fundamental element required by most organisms, including Brucella. Several researchers have suggested that the iron response regulator (irr) and rhizobial iron regulator (rirA) genes regulate iron acquisition by Brucella abortus, influencing heme synthesis by and virulence of this pathogen. However, little is known about another Brucella species, Brucella melitensis. In this research, we successfully constructed two mutants: M5-90Δirr and M5-90ΔrirA. The adhesion, invasion, and intracellular survivability of these two mutants were evaluated in RAW264.7 cells infected with 1 × 106 CFU of M5-90Δirr, M5-90ΔrirA, or M5-90. We also tested the sensitivity of cells to hydrogen peroxide and their ability to grow. In addition, the virulence of these two mutants was evaluated in BALB/c mice. The results showed that the ability of these two mutants to invade and adhere inside the murine macrophages RAW264.7 was attenuated but their ability to replicate intracellularly was strengthened, enhancing the resistance to hydrogen peroxide. The M5-90Δirr mutant showed stronger growth ability than the parental strain under iron-limiting conditions. No differences were observed in the number of bacteria in spleen between M5-90 and M5-90Δirr at 7 or 15 days postinfection. However, the number of M5-90ΔrirA in spleen reduced significantly at 15 days postinfection. The splenic index of the M5-90Δirr group is evidently lower than that of M5-90. This is the first report that irr and rirA genes of B. melitensis are associated not only with virulence but also with growth ability. Together, our data suggest that M5-90Δirr is a promising Brucella vaccine candidate.


Assuntos
Proteínas de Bactérias/genética , Brucella melitensis/genética , Brucella melitensis/patogenicidade , Regulação Bacteriana da Expressão Gênica/fisiologia , Ferro/metabolismo , Fatores de Transcrição/genética , Animais , Anti-Infecciosos Locais/toxicidade , Western Blotting , Vacina contra Brucelose/imunologia , Brucelose/prevenção & controle , Contagem de Colônia Microbiana , Feminino , Peróxido de Hidrogênio/toxicidade , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Baço/microbiologia , Virulência/genética
12.
J Immunol Res ; 2020: 5948256, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104715

RESUMO

Obese mice exhibited more lymphocytes in the bronchoalveolar lavage fluid and milder lung injury after Escherichia coli (E. coli) infection. However, it remained unclear whether the spleen contributed to the effect of obese mice with infection. The study was purposed to reveal the histopathological changes of the spleen caused by oxidative stress and inflammation in diet-induced obesity (DIO) mice challenged by Escherichia coli. After infection, the spleen tissues were obtained in normal and DIO mice at 0 h (uninfected), 12 h, 24 h, and 72 h postinfection. Results revealed that DIO mice have higher contents of resistin, TNF-α, IL-6, and IL-1ß in the spleen than normal mice and lower concentrations of GSH-Px, SOD, and CAT and higher MDA than normal mice. After an intranasal drip of E. coli, the activities of GSH-Px, SOD, and CAT in the DIO mice were elevated and the content of MDA declined. The activities of SOD and CAT in the normal mice declined, and the content of MDA was elevated. Moreover, the contents of TNF-α, IL-6, and IL-1ß in the spleen declined in DIO mice at 24 and 72 h, although the contents of leptin, resistin, TNF-α, IL-6, and IL-1ß were elevated at 12 h. The contents of resistin, TNF-α, IL-6, and IL-1ß were elevated in normal mice at 12 and 24 h. Those results indicated that obesity elevated splenic oxidation and inflammatory levels, but it enhanced antioxidant capacity and reduced cytokine levels of the spleen in mice to resist splenic injury after an intranasal drip of E. coli.


Assuntos
Antioxidantes/metabolismo , Citocinas/metabolismo , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Escherichia coli , Obesidade/metabolismo , Baço/metabolismo , Baço/microbiologia , Animais , Biomarcadores , Biópsia , Modelos Animais de Doenças , Infecções por Escherichia coli/diagnóstico , Fibrose , Camundongos , Obesidade/etiologia , Estresse Oxidativo , Baço/patologia , Avaliação de Sintomas
13.
Fish Shellfish Immunol ; 98: 585-594, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32004616

RESUMO

Oil-adjuvant formulated formalin killed cells of Flavobacterium psychrophilum (FKC + Adj) is strongly effective against bacterial cold-water disease (BCWD) in ayu Plecoglossus altivelis. In this study, we aimed to understand mechanisms underlying the strong protection by the vaccine in ayu. Antibody titer of FKC + Adj and formalin-killed cells (FKC) group was significantly higher than those of modified cytophaga broth injected (MCY) group and MCY with the adjuvant (MCY + Adj) group. The highest antibody titer was observed in FKC + Adj group. Granulomatous inflammation without lymphocyte cuff was observed in the spleen and trunk kidney of FKC + Adj and MCY + Adj group, while the size of the granuloma was bigger in FKC + Adj than in MCY + Adj group. Gene expression level for IL-8 was significantly up-regulated in FKC + Adj group at 4 weeks after the vaccination. In contrast, IL-10 gene expression level was significantly suppressed in FKC + Adj at 4 weeks after the vaccination. F. psychrophilum was almost cleared in the spleen and trunk kidney of FKC + Adj group within 2 days after the challenge. Fluorescent immunohistochemistry showed that a lot of bacterial signals were detected in the spleen and trunk kidney of challenged fish in MCY, FKC and MCY + Adj group. However, the fluorescent signal was not detected in the organs of FKC + Adj group after the challenge. These data suggest that F. psychrophilum is immediately cleared in FKC + Adj vaccinated fish and both specific antibody and activation of phagocytes are essential to clear F. psychrophilum in ayu.


Assuntos
Imunidade Adaptativa , Adjuvantes Imunológicos/administração & dosagem , Vacinas Bacterianas/administração & dosagem , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/imunologia , Óleos/administração & dosagem , Osmeriformes/imunologia , Animais , Doenças dos Peixes/imunologia , Infecções por Flavobacteriaceae/imunologia , Infecções por Flavobacteriaceae/microbiologia , Rim/microbiologia , Baço/microbiologia , Vacinas de Produtos Inativados/administração & dosagem
14.
Genome Res ; 30(2): 276-286, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31992612

RESUMO

Connections between the microbiome and health are rapidly emerging in a wide range of diseases. However, a detailed mechanistic understanding of how different microbial communities are influencing their hosts is often lacking. One method researchers have used to understand these effects are germ-free (GF) mouse models. Differences found within the organ systems of these model organisms may highlight generalizable mechanisms that microbiome dysbioses have throughout the host. Here, we applied multiplexed, quantitative proteomics on the brains, spleens, hearts, small intestines, and colons of conventionally raised and GF mice, identifying associations to colonization state in over 7000 proteins. Highly ranked associations were constructed into protein-protein interaction networks and visualized onto an interactive 3D mouse model for user-guided exploration. These results act as a resource for microbiome researchers hoping to identify host effects of microbiome colonization on a given organ of interest. Our results include validation of previously reported effects in xenobiotic metabolism, the innate immune system, and glutamate-associated proteins while simultaneously providing organism-wide context. We highlight organism-wide differences in mitochondrial proteins including consistent increases in NNT, a mitochondrial protein with essential roles in influencing levels of NADH and NADPH, in all analyzed organs of conventional mice. Our networks also reveal new associations for further exploration, including protease responses in the spleen, high-density lipoproteins in the heart, and glutamatergic signaling in the brain. In total, our study provides a resource for microbiome researchers through detailed tables and visualization of the protein-level effects of microbial colonization on several organ systems.


Assuntos
Disbiose/genética , Microbioma Gastrointestinal/genética , Interações Hospedeiro-Patógeno/genética , Proteômica , Animais , Encéfalo/metabolismo , Encéfalo/microbiologia , Colo/metabolismo , Colo/microbiologia , Disbiose/microbiologia , Coração/microbiologia , Humanos , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Fígado/metabolismo , Fígado/microbiologia , Camundongos , Baço/metabolismo , Baço/microbiologia
15.
Cell Rep ; 30(4): 1129-1140.e5, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31995754

RESUMO

Plasma membrane damage and cell death during processes such as necroptosis and apoptosis result from cues originating intracellularly. However, death caused by pore-forming agents, like bacterial toxins or complement, is due to direct external injury to the plasma membrane. To prevent death, the plasma membrane has an intrinsic repair ability. Here, we found that repair triggered by pore-forming agents involved TMEM16F, a calcium-activated lipid scramblase also mutated in Scott's syndrome. Upon pore formation and the subsequent influx of intracellular calcium, TMEM16F induced rapid "lipid scrambling" in the plasma membrane. This response was accompanied by membrane blebbing, extracellular vesicle release, preserved membrane integrity, and increased cell viability. TMEM16F-deficient mice exhibited compromised control of infection by Listeria monocytogenes associated with a greater sensitivity of neutrophils to the pore-forming Listeria toxin listeriolysin O (LLO). Thus, the lipid scramblase TMEM16F is critical for plasma membrane repair after injury by pore-forming agents.


Assuntos
Anoctaminas/metabolismo , Toxinas Bacterianas/toxicidade , Membrana Celular/metabolismo , Vesículas Extracelulares/metabolismo , Proteínas de Choque Térmico/toxicidade , Proteínas Hemolisinas/toxicidade , Fosfatidilserinas/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Timócitos/metabolismo , Animais , Anoctaminas/genética , Cálcio/metabolismo , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Membrana Celular/efeitos dos fármacos , Vesículas Extracelulares/efeitos dos fármacos , Listeria monocytogenes/metabolismo , Listeria monocytogenes/patogenicidade , Fígado/citologia , Fígado/metabolismo , Fígado/microbiologia , Fígado/patologia , Lipídeos de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Varredura , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/microbiologia , Neutrófilos/patologia , Proteínas de Transferência de Fosfolipídeos/genética , Baço/citologia , Baço/metabolismo , Baço/microbiologia , Baço/patologia , Timócitos/efeitos dos fármacos , Timócitos/ultraestrutura
16.
Infect Immun ; 88(3)2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31907194

RESUMO

Yersinia pestis is the causative agent of bubonic, pneumonic, and septicemic plague. We demonstrate that Toll-like receptor 2-deficient (TLR2-/-) mice are resistant to septicemic infection by the KIM5 strain of Y. pestis but not to infection by the CO92 Δpgm strain. This resistance is dependent on TLR2, the route of infection, and the isoform of YopJ. Elevated bacterial burdens were found in the spleens of CO92 Δpgm-infected animals by 24 h postinfection and in the livers by 4 days. The YopJ isoform present contributed directly to cytotoxicity and inflammatory cytokine production of bone marrow-derived macrophages from TLR2-/- mice. Immune cell trafficking is altered in CO92 Δpgm infections, with an increased neutrophil infiltration to the spleen 5 days postinfection. Immune cell infiltration to the liver was greater and earlier in KIM5-infected TLR2-/- mice. The functionality of the immune cells was assessed by the ability to develop reactive oxygen and nitrogen species. Our data suggest an inhibition of granulocytes in forming these species in CO92 Δpgm-infected TLR2-/- mice. These findings suggest that resistance to KIM5 in TLR2-/- mice is dependent on early immune cell trafficking and functionality.


Assuntos
Peste/imunologia , Receptor 2 Toll-Like/deficiência , Yersinia pestis/patogenicidade , Animais , Carga Bacteriana , Proteínas de Bactérias/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Granulócitos/metabolismo , Fígado/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Neutrófilos/metabolismo , Peste/metabolismo , Peste/microbiologia , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Baço/imunologia , Baço/microbiologia , Receptor 2 Toll-Like/imunologia , Virulência/genética , Yersinia pestis/genética
17.
Immunology ; 159(4): 404-412, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31909831

RESUMO

Dendritic cells (DCs) are potent immune cells that control innate and adaptive immune responses. Previous studies have shown that the DCs are required for protection against Staphylococcus aureus infection. However, the role of conventional DC (cDC) subsets during S. aureus infection in vivo has not been well investigated. In this study, we examined the function of spleen DC subsets in the activation of immunity against S. aureus infection. C57BL/6 mice were infected intravenously with S. aureus and DC and T-cell activation were analyzed in vivo. We found that the spleen CD8α- cDCs phagocytosed S. aureus more efficiently than type-1 conventional DCs (cDC1s) did. Moreover, the CD8α- cDCs contributed to the production of pro-inflammatory cytokines in response to S. aureus infection, whereas the cDC1s did not. In addition, infection with S. aureus promoted an increase in the number of Vß T cells. The CD4+ and CD8+ Vß T cells up-regulated the production of interferon-γ (IFN-γ) and interleukin-17 (IL-17) in response to S. aureus infection. Importantly, the induction of IFN-γ and IL-17 production in CD4+ and CD8+ Vß T cells was mediated by S. aureus-stimulated CD8α- cDCs, whereas cDC1s failed to promote IFN-γ and IL-17 production in the cells. Therefore, these data suggested that the spleen CD8α- cDCs are the main DC subsets for induction of S. aureus superantigen-specific immunity.


Assuntos
Antígenos CD8/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Linfócitos T CD4-Positivos/patologia , Antígenos CD8/deficiência , Antígenos CD8/genética , Linfócitos T CD8-Positivos/microbiologia , Linfócitos T CD8-Positivos/patologia , Linhagem da Célula/imunologia , Células Dendríticas/microbiologia , Expressão Gênica , Interações Hospedeiro-Patógeno/imunologia , Imunidade Celular , Interferon gama/genética , Interferon gama/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Baço/imunologia , Baço/microbiologia , Baço/patologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/patogenicidade
18.
Protein Pept Lett ; 27(3): 236-242, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31746288

RESUMO

BACKGROUND: Host-directed therapies are a comparatively new and promising method for the treatment of tuberculosis. A variety of host pathways, vaccines and drugs have the potential to provide novel adjunctive therapies for the treatment of tuberculosis. In this connection, we have earlier reported the immunotherapeutic potential of N-formylated N-terminal peptide of glutamine synthetase of Mycobacterim tuberculosis H37Rv (Mir SA and Sharma S, 2014). Now in the present study, we investigated the immunotherapeutic effect of N-terminally formylated internal-peptide 'f- MLLLPD' of mycobacterial glutamine synthetase (Rv2220) in mouse model of tuberculosis. METHODS: The N-terminally formylated peptide, f-MLLLPD was tested for its potential to generate Reactive Oxygen Species (ROS) in murine neutrophils. Further, its therapeutic effect alone or in combination with anti-tubercular drugs was evaluated in mouse model of tuberculosis. RESULTS: The f-MLLLPD peptide treatment alone and in combination with ATDs reduced the bacterial load (indicated as colony forming units) in lungs of infected mice by 0.58 (p<0.01) and 2.92 (p<0.001) log10 units respectively and in their spleens by 0.46 (p<0.05) and 2.46 (p<0.001) log10 units respectively. In addition, the observed histopathological results correlated well with the CFU data. CONCLUSION: The results of the current study show that f-MLLLPD peptide confers an additional therapeutic efficacy to the anti-tuberculosis drugs.


Assuntos
Glutamato-Amônia Ligase/química , Isoniazida/administração & dosagem , Mycobacterium tuberculosis/enzimologia , N-Formilmetionina Leucil-Fenilalanina/administração & dosagem , Rifampina/administração & dosagem , Tuberculose/tratamento farmacológico , Animais , Carga Bacteriana/efeitos dos fármacos , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Glutamato-Amônia Ligase/imunologia , Isoniazida/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Camundongos , Mycobacterium tuberculosis/imunologia , N-Formilmetionina Leucil-Fenilalanina/imunologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Rifampina/farmacologia , Baço/efeitos dos fármacos , Baço/microbiologia , Tuberculose/imunologia
19.
Mycoses ; 63(1): 30-37, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31514231

RESUMO

Hepatosplenic fungal infection (HSFI) is a severe invasive fungal infection observed during neutrophil recovery in patients with acute leukaemia treated with intensive chemotherapy. Retrospective analysis including all paediatric haematological malignancies patients with HSC treated in Children Cancer Hospital Egypt (2013-2018). Twenty-five patients with acute leukaemia developed HSFI (19 patients diagnosed as hepatosplenic candidiasis). Most of the cases (92%) occurred during the induction phase. Organs affected were as follows: liver in 18 patients, renal in 13 patients, spleen in 12 patients, skin in four patients and retina in one patient. Five (20%) patients had proven HSC, 14 (56%) probable and six (24%) possible HSFI. Ten patients had a PET-CT for response assessment. Candida tropicalis was the most common isolated spp. from blood/tissue culture. Six (24%) patients developed HSFI on top of antifungal prophylaxis. Steroids were given in 12 (52%) patients with HSFI as immune reconstitution syndrome (IRS). Caspofungin was the first line of treatment in 14 (56%) patients, liposomal amphotericin B in six (24%) patients and azoles in five (20%) patients. HSFI was associated with delayed of intensification phase of chemotherapy (median 42 days). The success rate was reported in 24 patients with complete response (68%) and partial response in (28%) patients, while failure (death) seen in 1(4%) patient. HSC is still a major challenge in paediatric leukaemias patients with impact on treatment delay and survival outcome. PET scan, non-culture diagnostics and steroid role evidence in IRS are growing. Antifungal stewardship for screening, early detection for high-risk patients and better response assessment is challenging.


Assuntos
Antifúngicos/uso terapêutico , Candidíase , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/microbiologia , Adolescente , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Candidíase/patologia , Criança , Pré-Escolar , Egito , Feminino , Humanos , Rim/microbiologia , Rim/patologia , Leucemia/complicações , Leucemia/microbiologia , Fígado/microbiologia , Fígado/patologia , Masculino , Neutropenia/complicações , Neutropenia/microbiologia , Retina/microbiologia , Retina/patologia , Estudos Retrospectivos , Pele/microbiologia , Pele/patologia , Baço/microbiologia , Baço/patologia , Resultado do Tratamento
20.
Appl Microbiol Biotechnol ; 104(1): 319-334, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758235

RESUMO

Positive modulation of gut microbiota in laying chickens may offer a strategy for reduction of Salmonella Typhimurium shedding and production of safer poultry products. In the current study, the caecal luminal microbiota of laying chicks was studied using 16S rRNA amplicon sequencing on DNA obtained from the chicks that were offered supplementation with commercial probiotics, synbiotics and/or Salmonella Typhimurium challenge. The load of Salmonella Typhimurium in various organs was quantified. Irrespective of the probiotics and synbiotics supplementation and Salmonella Typhimurium challenge, caecal microbiota was dominated by 22 distinct bacterial genera and 14 families that clustered into Actinobacteria, Proteobacteria and Firmicutes at phylum level. Taken together, probiotics and synbiotics supplementation increased (false discovery rate; FDR < 0.05) the abundance of Ruminococcus, Trabulsiella, Bifidobacterium, Holdemania and Oscillospira, indicating their role in maintaining gut health through lowering luminal pH and digestion of complex polysaccharides. Salmonella Typhimurium challenge decreased the abundance of Trabulsiella, Oscillospira, Holdemania, Coprococcus, Bifidobacterium and Lactobacillus and increased Klebsiella and Escherichia, indicating its role in caecal dysbiosis. Although probiotics and synbiotics supplementation positively modulated the caecal microbiota, they were not effective in significantly (P > 0.05) reducing Salmonella Typhimurium load in caecal tissue and invasion into vital organs such as liver and spleen. The early colonisation of laying chick caeca by probiotics and synbiotics had the potential to positively influence luminal microbiota; however, the microbial abundance and diversity were not sufficient to significantly reduce the shedding of Salmonella Typhimurium in faeces or invasion into internal organs during this study.


Assuntos
Derrame de Bactérias , Ceco/microbiologia , Microbiota , Probióticos/administração & dosagem , Salmonelose Animal/microbiologia , Simbióticos/administração & dosagem , Ração Animal/microbiologia , Animais , Carga Bacteriana , Galinhas/microbiologia , Fezes/microbiologia , Feminino , Fígado/microbiologia , Doenças das Aves Domésticas/microbiologia , RNA Ribossômico 16S , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidade , Baço/microbiologia
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