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1.
Nat Genet ; 51(10): 1540-1548, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31570888

RESUMO

Rhizoctonia solani is a widely distributed phytopathogen that causes banded leaf and sheath blight in maize and sheath blight in rice. Here, we identified an F-box protein (ZmFBL41) that confers resistance to banded leaf and sheath blight through a genome-wide association study in maize. Rice overexpressing ZmFBL41 showed elevated susceptibility to R. solani. Two amino acid substitutions in this allele prevent its interaction with ZmCAD, which encodes the final enzyme in the monolignol biosynthetic pathway, resulting in the inhibition of ZmCAD degradation and, consequently, the accumulation of lignin and restriction of lesion expansion. Knocking out the ZmCAD-homologous gene OsCAD8B in rice enhanced susceptibility to R. solani. The results reveal a susceptibility mechanism in which R. solani targets the host proteasome to modify the secondary metabolism of the plant cell wall for its invasion. More importantly, it provides an opportunity to generate R. solani-resistant varieties of different plant species.


Assuntos
Resistência à Doença/imunologia , Variação Genética , Doenças das Plantas/imunologia , Folhas de Planta/imunologia , Proteínas de Plantas/genética , Rhizoctonia/fisiologia , Zea mays/imunologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Zea mays/genética , Zea mays/microbiologia
2.
Fish Shellfish Immunol ; 94: 916-923, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31604151

RESUMO

This study investigates the possible effects of using Lactobacillus fermentum (LF) and/or ferulic acid (FA) in common carp (Cyprinus carpio) on some immunological parameters as well as resistance against Aeromonas hydrophila. Four diets were prepared including control diet and three diets supplemented with LF (108 CFU/g), FA (100 mg kg-1) or LF + FA (108 CFU/g + 100 mg kg-1). After 8 weeks, fish fed LF or/and FA had significantly higher final body weight, weight gain, and specific growth rate when compared to control group (P < 0.05). The feed conversion ratio of fish fed LF or/and FA were noticeably lower than control (P < 0.05). No alterations were observed in case of haematological parameters except red blood cells (RBCs), white blood cells (WBCs), hemoglobin (Hb), and hematocrit (HCT) which were significantly (P < 0.05) increased in fish fed FA or those fed both LF and FA. Also, the WBCs of fish treated with LF or/and FA were noticeably higher than control (P < 0.05). Feeding on LF and FA notably increased the serum total protein and albumin levels (P < 0.05). The serum respiratory burst and lysozyme activity were also enhanced (P < 0.05) in fish fed both LF or/and FA. In addition, evaluation of the serum antioxidant enzymes (catalase, glutathione peroxidase (GPX), and superoxide dismutase (SOD)) activity showed significant (P < 0.05) increase in fish fed FA or both LF and FA as compared to the control. Fish fed LF and FA supplemented diet had highest survival rate after experimental challenge with pathogenic A. hydrophila. The obtained results revealed that LF and/or FA can be used as beneficial feed additive to improve the immune responses and disease resistance in early stages of common carp culture.


Assuntos
Antioxidantes/metabolismo , Carpas/imunologia , Ácidos Cumáricos/metabolismo , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Lactobacillus fermentum/química , Aeromonas hydrophila/fisiologia , Ração Animal/análise , Animais , Ácidos Cumáricos/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Infecções por Bactérias Gram-Negativas/imunologia , Probióticos/farmacologia , Distribuição Aleatória
3.
Fish Shellfish Immunol ; 94: 880-888, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31562894

RESUMO

The humpback grouper (Cromileptes altivelis) is a commercially valuable species of the family Epinephelidae; however, its marketization suffers from slow growth speed, low survival rate, and various pathogenic diseases. Lactococcus lactis and Schizochytrium limacinum are commonly used as immunostimulants due to their health benefits for the aquatic organisms. In the present study, we assessed the effects of dietary supplementation with L. lactis HNL12 combined with S. limacinum algal meal on the growth performances, innate immune response, and disease resistance of C. altivelis against Vibrio harveyi. The results showed that fish fed with a combination diet of L. lactis and S. limacinum exhibited significantly higher final weight, percent weight gain, and specific growth rate compared with groups fed with them alone. A bacterial challenge experiment indicated that the group fed with the L. lactis combined with S. limacinum diet achieved the highest relative percent of survival value (68.63%), suggesting that L. lactis and S. limacinum significantly improved the disease resistance against V. harveyi after a 4-week feeding trial. Moreover, the respiratory burst activity of macrophages of fish fed with a L. lactis combined with S. limacinum diet was significantly higher than that of fish fed the control diet after 1, 2, and 3 weeks of feeding. The serum superoxide dismutase of fish fed with a L. lactis combined with S. limacinum diet significantly increased compared to those fed the control diet after 1 and 2 weeks of feeding, while the serum alkaline phosphatase of fish fed with a L. lactis combined with S. limacinum diet after 2 and 4 weeks was significantly increased, compared to the control group. The serum lysozyme activities of fish fed with a L. lactis combined with S. limacinum diet significantly increased compared to the control group after 2 weeks of feeding. Furthermore, transcriptome sequencing of the C. altivelis head kidney was conducted to explore the immune-regulating effects of the L. lactis combined with S. limacinum diet on C. altivelis. A total of 86,919 unigenes, annotated by at least one of the reference databases (Nr, Swiss-Prot, GO, COG, and KEGG), were assembly yielded by de novo transcriptome. In addition, 157 putative differentially expressed genes (DEGs) were identified between the L. lactis combined with S. limacinum group and the control group. For pathway enrichment, the DEGs were categorized into nine KEGG pathways, which were mainly related to infective diseases, antigen processing and presentation, digestive system, and other immune system responses. The findings of this study suggest that the L. lactis combined with S. limacinum diet can induce positive effects on the growth, immunity, and disease resistance of C. altivelis against V. harveyi. This study expands our understanding of the synergistic combinations of probiotics and prebiotics in aquaculture.


Assuntos
Bass/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , Lactococcus lactis/química , Prebióticos , Probióticos/farmacologia , Estramenópilas/química , Adjuvantes Imunológicos/farmacologia , Animais , Bass/crescimento & desenvolvimento , Resistência à Doença/efeitos dos fármacos , Resistência à Doença/imunologia , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
4.
Fish Shellfish Immunol ; 94: 407-416, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521784

RESUMO

The aims of this study were to investigate the antibacterial, immunostimulatory and antioxidant properties of different derivatives of Oliveria decumbens, in vitro and in vivo. The GC-MS spectrometry analysis showed γ-terpinene as the most frequent compound in essential oil, whereas carvacrol and thymol were the most common ones in aromatic water. Plant essential oil and hydroethanolic extract showed a positive in vitro bactericidal activity against Streptococcus iniae as evaluated by disc diffusion, minimum inhibitory concentration and minimum bactericidal concentration methods. Also, in vivo resistance against S. iniae and immune and antioxidant responses of Nile tilapia (Oreochromis niloticus) were assayed after 60 days treatment with O. decumbens derivatives. Plant hydroethanolic extract and essential oil and their 1:1 combination were added to diet at 0 (negative control), 0.01, 0.1 and 1% (w:w). The plant aromatic water at doses of 0.0312, 0.0625 and 0.1250% were also used as bath treatment. The results showed that aromatic water at lowest dose was more effective than other treatments in increment of fish resistance against S. iniae (7.14% mortality in comparison with 50% mortalities in control fish) and modulation of post-challenge respiratory burst activity. The bactericidal activity and biochemical contents of skin mucus did not change significantly among treatments. The levels of superoxide dismutase and catalase antioxidant enzymes activities in spleen tissue were significantly higher in treatments received extract, essential oils and their combination in comparison to other groups, while treatments did not affect peroxidase level. In conclusion, administration of different derivatives of Oliveria decumbens showed remarkable antibacterial activity against streptococcosis and enhanced antioxidant status and post-challenge immunity in Nile tilapia.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antibacterianos/farmacologia , Apiaceae/química , Ciclídeos/imunologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Streptococcus iniae/efeitos dos fármacos , Adjuvantes Imunológicos/química , Ração Animal/análise , Animais , Antibacterianos/química , Antioxidantes/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/imunologia , Relação Dose-Resposta a Droga , Doenças dos Peixes/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Óleos Voláteis/química , Extratos Vegetais/química , Soro/efeitos dos fármacos , Soro/imunologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus iniae/fisiologia
5.
Fish Shellfish Immunol ; 94: 525-538, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31539572

RESUMO

Aquatic rhabdoviruses are globally significant pathogens associated with disease in both wild and cultured fish. Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus that causes the internationally regulated disease infectious hematopoietic necrosis (IHN) in most species of salmon. Yet not all naïve salmon exposed to IHNV become diseased, and the mechanisms by which some individuals evade or rapidly clear infection following exposure are poorly understood. Here we used RNA-sequencing to evaluate transcriptomic changes in sockeye salmon, a keystone species in the North Pacific and natural host for IHNV, to evaluate the consequences of IHNV exposure and/or infection on host cell transcriptional pathways. Immersion challenge of sockeye salmon smolts with IHNV resulted in approximately 33% infection prevalence, where both prevalence and viral kidney load peaked at 7 days post challenge (dpc). De novo assembly of kidney transcriptomes at 7 dpc revealed that both infected and exposed but noninfected individuals experienced substantial transcriptomic modification; however, stark variation in gene expression patterns were observed between exposed but noninfected, infected, and unexposed populations. GO and KEGG pathway enrichment in concert with differential expression analysis identified that kidney responses in exposed but noninfected fish emphasised a global pattern of transcriptional down-regulation, particularly for pathways involved in DNA transcription, protein biosynthesis and macromolecule metabolism. In contrast, transcriptomes of infected fish demonstrated a global emphasis of transcriptional up-regulation highlighting pathways involved in antiviral response, inflammation, apoptosis, and RNA processing. Quantitative PCR was subsequently used to highlight differential and time-specific regulation of acute phase, antiviral, inflammatory, cell boundary, and metabolic responsive transcripts in both infected and exposed but noninfected groups. This data demonstrates that waterborne exposure with IHNV has a dramatic effect on the sockeye salmon kidney transcriptome that is discrete between resistant and acutely susceptible individuals. We identify that metabolic, acute phase and cell boundary pathways are transcriptionally affected by IHNV and kidney responses to local infection are highly divergent from those generated as part of a disseminated response. These data suggest that primary resistance of naïve fish to IHNV may involve global responses that encourage reduced cellular signaling rather than promoting classical innate antiviral responses.


Assuntos
Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Salmão/genética , Salmão/imunologia , Transcriptoma/imunologia , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Vírus da Necrose Hematopoética Infecciosa/fisiologia , Rim/imunologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Carga Viral/fisiologia
6.
Fish Shellfish Immunol ; 94: 810-818, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31546037

RESUMO

Ginkgo biloba leaf is widely used in traditional medicine in China. The present study aimed to illustrate the effects of dietary Ginkgo biloba leaf extract (GBLE) on growth performance and immune responses in common carp infected by Aeromonas hydrophila. Six different diets either not treated (control) or treated with 0.5, 1, 2, 5 and 10 g/kg of GBLE were designed to feed the fishes for 8 weeks. The results indicated that, compared to the control groups, 10 g/kg dietary GBLE significantly increased body growth and feed utilization. In GBLE dietary groups, red blood cell levels, white blood cells, hematocrit, hemoglobin, total protein, albumin and globulin were significantly increased relative to the control groups. Dietary supplementation with 5 g/kg GBLE increased the phagocytic ratio, and phagocytic indexes increased in the 2, 5 and 10 g/kg groups relative to the control groups. Moreover, 2, 5 and 10 g/kg GBLE diets increased O2- production compared to the control groups. Additionally, GBLE diets stimulated lysozyme activity (in 10 g/kg group) and inhibited bactericidal activity (in 0.5, 2, 5 and 10 g/kg group). Quantitative real-time PCR showed that IL1ß, IL8, TNF-α, IL10, TGFß, and inducible enzyme genes were prone to decrease while SAA, hepcidin and GPX1 were increased due to the GBLE diet in the intestine. In the head-kidney, the GBLE treatment decreased IL1ß, IL8, TNF-α, IL10, TGFß, INOS and arginase gene expressions, whereas SOD upregulation was found in the GBLE condition. The mRNA expressions of IL1ß, IL8, TNF-α, IL10 and INOS were decreased, but SAA, hepcidin, GPX1 and SOD mRNA levels were increased in the spleen in the GBLE diet compared to the control. Additionally, diet supplemented with GBLE improved the survival rate infected with A. hydrophila. Our observations suggest that GBLE effectively enhanced growth performance, modulated immune-related gene expression. It improved survival rate of common carp after A. hydrophila infection and the optimum concentration we recommend is 10 g/kg of GBLE.


Assuntos
Carpas/imunologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Extratos Vegetais/metabolismo , Aeromonas hydrophila/fisiologia , Animais , Carpas/genética , Resistência à Doença/genética , Relação Dose-Resposta a Droga , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Extratos Vegetais/administração & dosagem , Distribuição Aleatória
7.
Fish Shellfish Immunol ; 93: 500-507, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377430

RESUMO

A feeding trial was conducted to evaluate the effects of different molar mass chitooligosaccharides (1000 Da, 3000 Da and 8000 Da) on growth, antioxidant capacity, non-specific immune response, and resistance to Aeromonas hydrophila in GIFT tilapia (Oreochromis niloticus). A total of 600 fish were divided into four treatments with five replicates of thirty fish per tank. The results showed that the supplementation of 1000 Da and 3000 Da COS significantly improved the growth performance and feed utilization in GIFT tilapia. The trend of decreasing total cholesterol, triglyceride, ALT, and ACP activity was observed in fish fed diet supplemented COS. The supplementation of 1000 Da and 3000 Da COS significantly improved the serum TAC activity, and decreased the serum MDA and catalase activities (P < 0.05). The lysozyme activity of blood, liver, and gills in fish fed diets supplemented with 1000 Da and 3000 Da COS was significantly higher than that of fish fed control diet after 56 days of feeding (P < 0.05). The phagocytic activity and phagocytic index of fish fed diets supplemented with 1000 Da and 3000 Da COS were significantly higher than those of fish fed control diet. Post-challenge test showed that fish mortality in 1000 Da, 3000 Da, and 8000 Da COS groups were significantly lower than that of fish in control group (P < 0.05). In conclusion, the present study indicated that dietary 1000 Da and 3000 Da COS supplementation could enhance more performance and immune response of GIFT tilapia than 8000 Da COS.


Assuntos
Antioxidantes/metabolismo , Ciclídeos/imunologia , Resistência à Doença/efeitos dos fármacos , Doenças dos Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , Oligossacarídeos/metabolismo , Aeromonas hydrophila/fisiologia , Ração Animal/análise , Animais , Ciclídeos/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/imunologia , Relação Dose-Resposta a Droga , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Imunidade Inata/imunologia , Oligossacarídeos/administração & dosagem
8.
Vet Parasitol ; 273: 60-66, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442895

RESUMO

Maternal antibody transmission via placenta and breastmilk are known to confer protection in infants. In this study, we investigated the maternal immunity transmission in pups delivered by rats infected with Trichinella spiralis and assessed the resulting resistance against subsequent parasitic infection. Our results revealed that parasite-specific IgG, IgG1 and IgG2a antibodies were present in pups prior to breastmilk ingestion (pre-milk), in which IgG and IgG1 antibodies persisted until week 8 after birth while parasite-specific IgG2a antibodies only lasted until week 4. After weaning on week 3, pups delivered by T. spiralis-infected dam and subsequently challenge-infected (immune-challenge) were found to possess higher mucosal IgG antibodies than control groups, whereas mucosal IgA levels were not significantly different across all groups. T. spiralis excretory-secretory antigen was discovered to react with pup sera until week 8, correlating with the resistance against parasitic infection which is represented by lessened worm burden. Upon T. spiralis infection at weeks 3 and 8, lower levels of eosinophil responses were detected in immune-challenge pups compared to naïve-challenge pups, indicating correlates of resistances in which ADCC may be involved. Findings from the present study demonstrate that resistances against T. spiralis infection in pups can be acquired by maternally-derived IgG, IgG1 and IgG2a antibody transmission through the placenta and breastmilk from T. spiralis-infected dam, which lasts until week 8.


Assuntos
Resistência à Doença/imunologia , Imunidade Materno-Adquirida/imunologia , Trichinella spiralis/imunologia , Triquinelose/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/metabolismo , Feminino , Proteínas de Helminto/metabolismo , Leite/imunologia , Placenta/imunologia , Gravidez , Ratos
9.
Nat Commun ; 10(1): 3813, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444353

RESUMO

Salicylic acid (SA)-mediated innate immune responses are activated in plants perceiving volatile monoterpenes. Here, we show that monoterpene-associated responses are propagated in feed-forward loops involving the systemic acquired resistance (SAR) signaling components pipecolic acid, glycerol-3-phosphate, and LEGUME LECTIN-LIKE PROTEIN1 (LLP1). In this cascade, LLP1 forms a key regulatory unit in both within-plant and between-plant propagation of immunity. The data integrate molecular components of SAR into systemic signaling networks that are separate from conventional, SA-associated innate immune mechanisms. These networks are central to plant-to-plant propagation of immunity, potentially raising SAR to the population level. In this process, monoterpenes act as microbe-inducible plant volatiles, which as part of plant-derived volatile blends have the potential to promote the generation of a wave of innate immune signaling within canopies or plant stands. Hence, plant-to-plant propagation of SAR holds significant potential to fortify future durable crop protection strategies following a single volatile trigger.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Resistência à Doença/imunologia , Doenças das Plantas/imunologia , Lectinas de Plantas/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Retroalimentação Fisiológica , Glicerofosfatos/imunologia , Glicerofosfatos/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Monoterpenos/imunologia , Monoterpenos/metabolismo , Ácidos Pipecólicos/imunologia , Ácidos Pipecólicos/metabolismo , Doenças das Plantas/microbiologia , Lectinas de Plantas/genética , Plantas Geneticamente Modificadas , Pseudomonas syringae/imunologia , Ácido Salicílico/imunologia , Ácido Salicílico/metabolismo , Transdução de Sinais/imunologia , Compostos Orgânicos Voláteis/imunologia
10.
Fish Shellfish Immunol ; 93: 1047-1055, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31425831

RESUMO

Nowadays, there is no suitable treatment for vibriosis in groupers. So an eco-efficient and environmentally friendly treatment is necessary for the grouper industry. Probiotic-feeding has been a promising strategy to control the bacterial pathogens in aquaculture. A new Bacillus velezensis strain named K2 was isolated from the intestinal tract of healthy grouper, and exhibited wide antimicrobial spectrum of against fish pathogens, including Vibrio harveyi, Vibrio alginolyticus, Aeromonas hydrophila, Aeromonas veronii, Aeromonas caviae, Enterococcus casseliflavus and Lactococcus garvieae. Moreover, results of the safety of B. velezensis K2 showed that intraperitoneal injection of K2 in healthy grouper did not cause any pathological abnormality or death, indicating this bacteria could be considered as a candidate probiotic in aquaculture. Groupers were fed with the diets containing 1 × 107 cfu/g of B. velezensis K2 for 4 weeks. Various immune parameters were examined at 1, 2, 3, and 4 weeks of post-feeding. Results showed that diets supplemented with K2 significantly increased serum acid phosphatase (ACP) activity (P < 0.05). Results of the mRNA expression of immune-related genes in the head kidney of hybrid grouper showed that the expression of lysozyme gene was significantly upregulated after 1 and 2 weeks of feeding (P < 0.05). A significant up-regulation of the expression of piscidin, IgM and MyD88 were detected at day 21, whereas the TLR3 and TLR5 showed lower expression compared to the controls during 21 days, and a significant decrease of TLR3 gene was found at day 28 (P < 0.05). After challenge with V. harveyi, the survival rate of fish administrated with the strain K2 for 28 days was signifiacantly higher than the controls without this strain (P < 0.05). These results collectively suggest that B. velezensis K2 is a potential probiotic species to improve health status and disease resistance and can be developed as a probiotic agent in grouper industry.


Assuntos
Bacillus/química , Bass/imunologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Probióticos/farmacologia , Ração Animal/análise , Animais , Bass/crescimento & desenvolvimento , Dieta/veterinária , Distribuição Aleatória , Vibrio/efeitos dos fármacos , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
11.
Fish Shellfish Immunol ; 93: 1041-1046, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31465870

RESUMO

Although the type I interferon-mediated increase of Mx1 and ISG15 gene expression in Epithelioma papulosum cyprini (EPC) cells has been reported, the antiviral role of Mx1 and ISG15 in EPC cells has not been investigated. In this study, to know the anti-viral hemorrhagic septicemia virus (VHSV) role of Mx1 and ISG15 of EPC cells, either Mx1 or ISG15 gene was knocked-out using a CRISPR/Cas9 system, and the progression of cytopathic effects (CPE) and viral growth were analyzed. Mx1 gene and ISG15 gene knockout EPC cells were successfully produced via CRISPR/Cas9 coupled with a single-cell cloning. Through the sequence analysis, one clone showing two heterozygous indel patterns in Mx1 gene and a clone showing three heterozygous indel patterns in ISG15 gene were selected for further analyses. Mx1 knockout EPC cells did not show any differences in VHSV-mediated CPE progression, even when pre-treated with polyinosinic:polycytidylic acid (poly I:C), compared to control EPC cells. These results suggest that Mx1 in EPC cells may be unfunctional to cytoplasmic RNA viruses. In contrast to Mx1, ISG15 knockout cells showed clearly hampered anti-VHSV activity even when pre-treated with poly I:C, indicating that ISG15 plays an important role in type I interferon-mediated anti-viral activity in EPC cells, which allowed VHSV to replicate more efficiently in ISG15 knockout cells than Mx1 knockout and control cells.


Assuntos
Sistemas CRISPR-Cas/imunologia , Cyprinidae/imunologia , Resistência à Doença/genética , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Expressão Gênica , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular Tumoral , Cyprinidae/genética , Resistência à Doença/imunologia , Doenças dos Peixes/genética , Técnicas de Inativação de Genes/veterinária , Septicemia Hemorrágica Viral/genética , Septicemia Hemorrágica Viral/imunologia , Interferon Tipo I/genética , Novirhabdovirus/fisiologia , Poli I-C/farmacologia , Análise de Sequência de DNA/veterinária , Análise de Sequência de Proteína/veterinária
12.
Fish Shellfish Immunol ; 93: 711-719, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31419532

RESUMO

In the present study, we aimed to screen the potential probiotic Bacillus subtilis isolated from the gut of healthy fish using in vitro assays and to evaluate its effect on Dabry's sturgeon (Acipenser dabryanus) using in vivo feeding experiments. Among the isolates, B. subtilis BSth-5 and BSth-19 exhibited antimicrobial effect against four sturgeon-pathogenic bacteria, including Aeromonas hydrophila, A. veronii, A. media, and Streptococcus iniae. The cell number of B. subtilis BSth-5 and BSth-19 changed little after 2 h of exposure to pH 3.0 or fresh Dabry's sturgeon bile at 2.5% and 5.0%. Meanwhile, B. subtilis BSth-5 and BSth-19 produced extracellular protease, cellulose, and lipase. And it was proved that B. subtilis BSth-5 and BSth-19 were harmless after injection of Dabry's sturgeon. One group of Dabry's sturgeon was fed a control diet and two groups were fed experimental diets containing 2.0 × 108 CFU/g BSth-5 (T1 group) or BSth-19 (T2 group) for 8 weeks. No significant differences in final weight, weight gain rate, and special growth rate were observed in the T1 and T2 groups compared to the control group (P > 0.05), but a significant improvement in survival rate was detected after 4 and 8 weeks of feeding (P < 0.05). After 8 weeks, serum total antioxidant capacity, total superoxide dismutase activity, and IgM levels were significantly higher in the T1 and T2 groups compared to the control group (P < 0.05). Moreover, serum lysozyme activity was significantly higher in the T1 group relative to the control group during the whole experiment period (P < 0.05); however, the differences were not significant between the T2 and control groups (P > 0.05). Serum malondialdehyde levels in the T1 and T2 groups were significantly lower than those in the control group after 4 weeks (P < 0.05). Sturgeons in the T1 and T2 groups showed a higher survival rate after Aeromonas hydrophila infection. To summarize, dietary supplementation with BSth-5 and BSth-19 could enhance the survival rate, antioxidant activity, serum immunity, and disease resistance in A. dabryanus.


Assuntos
Bacillus subtilis/química , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , Probióticos/farmacologia , Aeromonas hydrophila/fisiologia , Ração Animal/análise , Animais , Dieta/veterinária , Resistência à Doença/efeitos dos fármacos , Peixes/sangue , Peixes/crescimento & desenvolvimento , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária
13.
PLoS One ; 14(7): e0218034, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31318864

RESUMO

Despite substantial exposure to infectious pulmonary tuberculosis (TB) cases, some household contacts (HHC) never acquire latent TB infection (LTBI). Characterizing these "resisters" can inform who to study immunologically for the development of TB vaccines. We enrolled HHCs of culture-confirmed adult pulmonary TB in India who underwent LTBI testing using tuberculin skin test (TST) and QuantiFERON TB Gold Test-in-tube (QFT-GIT) at baseline and, if negative by both (<5mm TST and <0.35IU/mL QFT-GIT), underwent follow-up testing at 4-6 and/or 12 months. We defined persons with persistently negative LTBI tests at both baseline and followup as pLTBI- and resisters as those who had a high exposure to TB using a published score and remained pLTBI-. We calculated the proportion of resisters overall and resisters with complete absence of response to LTBI tests (0mm TST and/or QFT-GIT <0.01 IU/ml). Using random effects Poisson regression, we assessed factors associated with pLTBI-. Of 799 HHCs in 355 households, 67 (8%) were pLTBI- at 12 months; 52 (6.5%) pLTBI- in 39 households were resisters. Complete absence of response to LTBI tests was found in 27 (53%) resisters. No epidemiological characteristics were associated with the pLTBI- phenotype. LTBI free resisters among HHC exist but are uncommon and are without distinguishing epidemiologic characteristics. Assessing the genetic and immunologic features of such resister individuals is likely to elucidate mechanisms of protective immunity to TB.


Assuntos
Resistência à Doença/imunologia , Tuberculose Latente , Tuberculose Pulmonar , Adolescente , Adulto , Criança , Características da Família , Feminino , Humanos , Índia/epidemiologia , Tuberculose Latente/diagnóstico , Tuberculose Latente/epidemiologia , Tuberculose Latente/imunologia , Masculino , Teste Tuberculínico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/imunologia
14.
Fish Shellfish Immunol ; 93: 428-435, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31362090

RESUMO

The present study aimed to assess the possible effects of Assam tea (Camellia sinensis) extract (ATE) on growth performances, immune responses, and disease resistance of Nile tilapia, Oreochromis niloticus against Streptococcus agalactiae. Five levels of ATE were supplemented into the based diet at 0, 1, 2, 4, and 8 g kg-1 feed of Nile tilapia fingerlings (10.9 ±â€¯0.04 g initial weight) in triplicate. After four and eight weeks of feeding, fish were sampled to determine the effects of the tea supplements upon their growth performance, as well as serum and mucosal immune responses. A disease challenge using S. agalactiae was conducted at the end of the feeding trial. Fish fed ATE revealed significantly improved serum lysozyme, peroxidase, alternative complement (ACH50), phagocytosis, and respiratory burst activities compared to the basal control fed fish (P < 0.05). The mucus lysozyme and peroxidase activities were ameliorated through ATE supplementation in the tilapia diets. Supplementation of ATE significantly (P < 0.05) enhanced final body weight, weight gain, and specific growth rate; while a decreased feed conversion ratio was revealed at 2 g kg-1 inclusion level, after four and eight weeks. Challenge test showed that the relative percent survival (RSP) of fish in each treatment was 33.33%, 60.00%, 83.33%, 76.68%, and 66.68% in groups fed 0, 1, 2, 4, and 8 g kg-1, respectively. In summary, diets supplemented with ATE especially at 2 g kg-1 increased the humoral and mucosal immunity, enhanced growth performance, and offered higher resistance against S. agalactiae infection in Nile tilapia.


Assuntos
Camellia sinensis/química , Ciclídeos/imunologia , Resistência à Doença/efeitos dos fármacos , Doenças dos Peixes/imunologia , Extratos Vegetais/metabolismo , Ração Animal/análise , Animais , Ciclídeos/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/imunologia , Relação Dose-Resposta a Droga , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Folhas de Planta/química , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia
15.
Fish Shellfish Immunol ; 93: 336-343, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352117

RESUMO

The present investigation was performed to evaluate the efficiency of Zinc oxide (ZnO) as a fish feed additive in immunomodulation of Oreochromis niloticus. Fish were fed on ZnO nano-particles (nZnO) and conventional (ZnO) in two concentrations (30 and 60 mg/kg diet), in addition to the control fish which was fed on Zn free diet. After 6° days, the highest survival rate was recorded in the nZnO30 -supplemented group. The total antioxidant capacity (TAC) and antioxidant enzymes were improved in different dietary Zn supplementation, obviously in the nZnO30 -supplemented group, while the lowest antioxidant status was noticed nZnO60 supplemented fish. The lipid peroxides (MDA) level was diminished upon Zn supplementation, particularly in nZnO30-supplemented group but showed a significant elevation in the nZnO60-supplemented group. Furthermore, the immune parameters examined, lysozyme activity, bactericidal activity, and IgM were significantly higher in ZnO60, and nZnO30 supplemented groups. The C-reactive protein (CRP) level showed no significant increase in response to Zn supplementation in the both forms at level of 30 mg/kg diet, but showed marked elevation in nZnO60- supplemented group. The mRNA expression profile of both interleukin 8 (IL-8), interleukin 1, beta (IL-1ß) encoding genes showed an up-regulation that was found in all Zn- supplemented groups, but more pronounced in nZnO60-supplemented group. On the other hand, the expression pattern of myxovirus resistance (Mx)-encoding gene showed no remarkable difference between the Zn- supplemented and control fish. The expression level of CXC-chemokine, toll-like receptor 7 (TLR-7), immunoglobulin M heavy chain (IgM heavy chain) and interferon gamma (IFN-γ) gene was upregulated in Zn-supplemented groups particularly in the nZnO30- supplemented group. While, the lowest expression was found in nZnO60- and ZnO30-supplemented groups. Here, Zn supplementation promoted the immune and antioxidant strength in fish mainly in nano form at the level of 30 mg/kg diet but not at 60 mg/kg diet that disrupt the immune and antioxidant status and promote inflammatory response.


Assuntos
Ração Animal/análise , Ciclídeos/genética , Ciclídeos/imunologia , Resistência à Doença , Imunidade Inata/genética , Transcriptoma/imunologia , Óxido de Zinco/metabolismo , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/genética , Resistência à Doença/imunologia , Nanopartículas Metálicas/administração & dosagem , Óxido de Zinco/administração & dosagem
16.
Fish Shellfish Immunol ; 93: 726-731, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31265912

RESUMO

Application of traditional bait in aquaculture caused environment pollution and disease frequent occurrence. Residual coconut could be re-utilized to culture Spinibarbus sinensis as dietary supplement. Therefore, a novel integrated system of the improvement of yield, antioxidant and nonspecific immunity of Spinibarbus sinensis by dietary residual coconut was proposed and investigated. Spinibarbus sinensis could grow well in all supplement residual coconut groups. Survival rate, yield, whole fish body composition under 15-45% groups were increased compared with control group (CK). Bioactive substances (polyphenols and vitamin) in residual coconut enhanced AKP, ACP, phagocytic, SOD, CAT activities through up-regulating AKP, ACP, SOD, CAT genes expression levels. Theoretical analysis showed bioactive substances regulated these genes expressions and enzyme activities as stimulus signal, component, active center. Moreover, residual coconut improved mTOR and NF-kB signaling pathway. Furthermore, residual coconut inhibited Aeromonas hydrophila that increased resistance to diseases. This technology completed the solid waste recovery and the Spinibarbus sinensis culture simultaneously.


Assuntos
Antioxidantes/metabolismo , Óleo de Coco/metabolismo , Cyprinidae/imunologia , Resistência à Doença/imunologia , Imunidade Inata/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ração Animal/análise , Animais , Aquicultura/métodos , Óleo de Coco/administração & dosagem , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estudos de Viabilidade
17.
Vet Parasitol ; 270: 49-55, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213241

RESUMO

Variation in the timing of development of immunity to gastro-intestinal nematode parasites was assessed in resistant and resilient Romney selection lines exposed to mixed natural infection. From weaning, at mean 92 days-of-age, animals (n = 53) were sampled for faecal egg count (FEC) expressed as eggs per gram of faeces (epg), saliva for immunoglobulin (IgG and IgA) determination and fasted live weight (LW) every 10 days until 351 days-of-age. Overall, mean back-transformed FEC were consistently low for resistant animals (<200 epg) whereas resilient counterparts' FEC increased with time to reach a peak of 1400 epg at day 230 for females and 1800 epg for males at day 280 before declining to less than 500 epg by day 300, respectively (P < 0.001). Resistant lambs reached a threshold for Trichostrongylus colubriformis L3-specific IgG which was indicative of the presence of immunity earlier at 220.6 ± 8.8 days-of-age compared with resilient-line animals which reach this threshold 40 days later at 263.4 ± 6.9 days-of-age (P < 0.001). In addition, resistant females reached sexual maturity earlier compared with their resilient counterparts viz. 263.5 ± 3.7 c.f. 274.4 ± 3.4 days-of-age, respectively, (P = 0.048). Mean fasted live weight (LW) showed a selection line by time interaction (P < 0.001) which reflected greater LW in the early phase of the study in resilient males but increasing for all groups until day 280 before declining and being similar for all groups from day 330. In summary, differences appear to exist in the timing of immune development between these Romney lines, with resistant animals developing immunity earlier and these resistant-line animals also appear to be more physiologically mature at the same chronological age than resilient animals. These observations have implications on the timing of identification and selection of resistant animals.


Assuntos
Cruzamento , Resistência à Doença/imunologia , Doenças dos Ovinos/imunologia , Tricostrongilose/veterinária , Animais , Feminino , Masculino , Seleção Genética , Maturidade Sexual , Ovinos , Tricostrongilose/imunologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-31245299

RESUMO

Toxoplasma gondii is a successful protozoan parasite that cycles between definitive felid hosts and a broad range of intermediate hosts, including rodents and humans. Within intermediate hosts, this obligate intracellular parasite invades the small intestine, inducing an inflammatory response. Toxoplasma infects infiltrating immune cells, using them to spread systemically and reach tissues amenable to chronic infection. An intact immune system is necessary to control life-long chronic infection. Chronic infection is characterized by formation of parasite cysts, which are necessary for survival through the gastrointestinal tract of the next host. Thus, Toxoplasma must evade sterilizing immunity, but still rely on the host's immune response for survival and transmission. To do this, Toxoplasma exploits a central cost-benefit tradeoff in immunity: the need to escalate inflammation for pathogen clearance vs. the need to limit inflammation-induced bystander damage. What are the consequences of sustained inflammation on host biology? Many studies have focused on aspects of the immune response that directly target Toxoplasma growth and survival, commonly referred to as "resistance mechanisms." However, it is becoming clear that a parallel arm of the immune response has evolved to mitigate damage caused by the parasite directly (for example, egress-induced cell death) or bystander damage due to the inflammatory response (for example, reactive nitrogen species, degranulation). These so-called "disease tolerance" mechanisms promote tissue function and host survival without directly targeting the pathogen. Here we review changes to host metabolism, tissue structure, and immune function that point to disease tolerance mechanisms during Toxoplasma infection. We explore the impact tolerance programs have on the health of the host and parasite biology.


Assuntos
Resistência à Doença/imunologia , Interações Hospedeiro-Parasita/imunologia , Toxoplasma/imunologia , Toxoplasmose/imunologia , Animais , Interações Hospedeiro-Parasita/fisiologia , Humanos , Tolerância Imunológica , Imunidade Inata/imunologia , Inflamação , Toxoplasma/patogenicidade , Toxoplasma/fisiologia , Toxoplasmose/parasitologia
19.
Int J Mol Sci ; 20(12)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248151

RESUMO

Pathogen-induced cell death is closely related to plant disease susceptibility and resistance. The cucumber (Cucumis sativus L.) mildew resistance locus O (CsMLO1) and calmodulin (CsCaM3) genes, as molecular components, are linked to nonhost resistance and hypersensitive cell death. In this study, we demonstrate that CsMLO1 interacts with CsCaM3 via yeast two-hybrid, firefly luciferase (LUC) complementation and bimolecular fluorescence complementation (BiFC) experiments. A subcellular localization analysis of green fluorescent protein (GFP) fusion reveals that CsCaM3 is transferred from the cytoplasm to the plasma membrane in Nicotiana benthamiana, and CsCaM3 green fluorescence is significantly attenuated via the coexpression of CsMLO1 and CsCaM3. CsMLO1 negatively regulates CsCaM3 expression in transiently transformed cucumbers, and hypersensitive cell death is disrupted by CsCaM3 and/or CsMLO1 expression under Corynespora cassiicola infection. Additionally, CsMLO1 silencing significantly enhances the expression of reactive oxygen species (ROS)-related genes (CsPO1, CsRbohD, and CsRbohF), defense marker genes (CsPR1 and CsPR3) and callose deposition-related gene (CsGSL) in infected cucumbers. These results suggest that the interaction of CsMLO1 with CsCaM3 may act as a cell death regulator associated with plant immunity and disease.


Assuntos
Calmodulina/metabolismo , Cucumis sativus/fisiologia , Resistência à Doença , Interações Hospedeiro-Patógeno/imunologia , Doenças das Plantas/etiologia , Imunidade Vegetal , Proteínas de Plantas/metabolismo , Calmodulina/genética , Morte Celular , Resistência à Doença/genética , Resistência à Doença/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ordem dos Genes , Inativação Gênica , Vetores Genéticos , Interações Hospedeiro-Patógeno/genética , Espaço Intracelular , Fenótipo , Proteínas de Plantas/genética , Ligação Proteica
20.
Fish Shellfish Immunol ; 91: 233-240, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102711

RESUMO

This investigation was aimed to determine the efficacy of coriander seed extract (Coriandrum sativum) on physiological responses, immunity and disease resistance of rainbow trout, Oncorhynchus mykiss for eight weeks. A total number of six hundred rainbow trout (62 ±â€¯0.81 g) were divided into four feeding groups including 0 (control), 0.5%, 1% and 2% of coriander seed extract (CSE). In the present study, rainbow trout fed with 2% of CSE showed significantly higher values of specific growth rate (SGR), final weight (FW) and condition factor (CF) in comparison with control group after eight weeks (P < 0.05). Regarding hematological indices results, the 2% dosage of CSE showed the highest amount of hematocrit and hemoglobin compared to control group (P < 0.05). In addition, significant improvement of lysozyme and alternative complement activity, were observed in 2% of CSE treatment (P < 0.05). After eight weeks post-feeding, 30 fish from each treatment were challenged with Yersinia ruckeri for 14 days. The findings presented that fish fed with CES, especially 2% of CSE inclusion, improved survival rate of rainbow trout against Y. ruckeri; however, there were no significant differences among the fish in control and treatment groups at the end of the eight weeks feeding with coriander seed extract. The present study demonstrated, dietary incorporation of coriander extract can improve growth factors, immunological indices and resistance of rainbow trout (O. mykiss) against Y. ruckeri infection.


Assuntos
Coriandrum/química , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Oncorhynchus mykiss/fisiologia , Extratos Vegetais/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/efeitos dos fármacos , Oncorhynchus mykiss/crescimento & desenvolvimento , Oncorhynchus mykiss/imunologia , Extratos Vegetais/administração & dosagem , Sementes/química , Yersiniose/imunologia , Yersinia ruckeri/fisiologia
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