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1.
Vet Immunol Immunopathol ; 213: 109885, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307670

RESUMO

Protec™ is a commercial aquafeed (Skretting Italia) containing a combination of glucans, vitamin C, vitamin E and zinc (immune support pack). No research information concerning its capability to improve fish immune response is available, so in this study the potential immunomodulatory effects of Protec™ were investigated in rainbow trout (Oncorhynchus mykiss). Head kidney (HK) leukocytes from adult fish (100 g, n = 6) were in vitro incubated with Protec™ immune support pack resulting in significantly higher respiratory burst activity and proliferation. Specifically, sonicated Protec™ immune support pack (160 µg/ml) induced a respiratory burst response similar to that promoted by zymosan and lipopolysaccharide (LPS), while non-sonicated Protec™ immune support pack induced a response comparable to that of cells stimulated with phorbol myristate acetate (PMA). Moreover, the proliferation of leukocytes exposed to sonicated Protec™ immune support pack (20 µg/ml) was significantly higher than that of cells stimulated with zymosan, and it was comparable to the proliferation of cells stimulated with phytohaemagglutinin (PHA) and LPS. Afterwards, a feeding trial was performed in a rainbow trout farm. Two groups of juvenile rainbow trout (10 g) were acclimated for 7 weeks before the experiment and fed daily with a commercial control diet (Optiline HE, Skretting Italia) at 2% BW/day. At the end of acclimation, one group of fish was fed with Protec™ diet (Skretting Italia) at 2% BW/day whereas the other group continued to feed the control diet at the same level for further 4 weeks. Then, fish were sampled (HK leukocytes from n = 6 fish/group, serum from n = 12 fish/group) or intraperitoneally vaccinated against lactococcosis (n = 160/dietary group/time point). Fish fed the same diets for further 4 weeks after vaccination, then feeding returned to the control diet in both groups until the end of the trial. The specific antibody response was recorded at 4 and 8 weeks after vaccination (n = 12 fish/group). The administration of Protec™ significantly enhanced the respiratory burst activity of leukocytes and the synthesis of specific IgM against Lactococcus garvieae, whereas the serum lysozyme activity was unaffected. The present research suggests that the administration of Protec™ can improve both innate and adaptive immune response of rainbow trout, proving to be an interesting strategy for enhancing the immune reactivity of fish to vaccines.


Assuntos
Ração Animal , Anticorpos Antibacterianos/sangue , Infecções por Bactérias Gram-Positivas/veterinária , Imunidade Inata , Lactococcus , Oncorhynchus mykiss/imunologia , Imunidade Adaptativa , Adjuvantes Imunológicos/administração & dosagem , Animais , Proliferação de Células , Dieta/veterinária , Feminino , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Imunoglobulina M/sangue , Leucócitos/imunologia , Oncorhynchus mykiss/microbiologia , Explosão Respiratória
2.
Fish Shellfish Immunol ; 92: 690-697, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276788

RESUMO

Macrophage expressed gene 1 (Mpeg1) is a molecule that can form pores and destroy the cell membrane of invading pathogens. In this study, we identified two Mpeg1 isoforms from the orange-spotted grouper (Epinephelus coioides) and named them EcMpeg1a and EcMpeg1b. Predicted proteins of the two EcMpeg1s contained a signal peptide, a conserved membrane attack complex/perforin (MACPF) domain, a transmembrane segment, and an intracellular region. Sequence alignment demonstrated that two EcMpeg1 proteins share a high sequence identity with that of other teleosts. Tissue distribution analysis showed that EcMpeg1s were expressed in all tissues tested in healthy grouper, with the highest expression in the head kidney and spleen. After infection with the ciliate parasite Cryptocaryon irritans, expression of the two EcMpeg1s was significantly upregulated in the spleen and gills. Furthermore, the recombinant EcMpeg1a showed antiparasitic and antibacterial activity against Gram-negative and -positive bacteria, whereas EcMpeg1b had an inhibitory effect only against Gram-positive bacteria. These results indicated that EcMpeg1s play an important role in the host response against invading pathogens.


Assuntos
Bass/genética , Bass/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Sequência de Aminoácidos , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Proteínas de Membrana/química , Filogenia , Alinhamento de Sequência/veterinária
3.
Int J Mol Sci ; 20(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167367

RESUMO

Bacteria from the species Trueperella pyogenes are a part of the biota of skin and mucous membranes of the upper respiratory, gastrointestinal, or urogenital tracts of animals, but also, opportunistic pathogens. T. pyogenes causes a variety of purulent infections, such as metritis, mastitis, pneumonia, and abscesses, which, in livestock breeding, generate significant economic losses. Although this species has been known for a long time, many questions concerning the mechanisms of infection pathogenesis, as well as reservoirs and routes of transmission of bacteria, remain poorly understood. Pyolysin is a major known virulence factor of T. pyogenes that belongs to the family of cholesterol-dependent cytolysins. Its cytolytic activity is associated with transmembrane pore formation. Other putative virulence factors, including neuraminidases, extracellular matrix-binding proteins, fimbriae, and biofilm formation ability, contribute to the adhesion and colonization of the host tissues. However, data about the pathogen-host interactions that may be involved in the development of T. pyogenes infection are still limited. The aim of this review is to present the current knowledge about the pathogenic potential and virulence of T. pyogenes.


Assuntos
Actinomycetaceae/fisiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Actinomycetaceae/classificação , Actinomycetaceae/patogenicidade , Animais , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Reservatórios de Doenças , Genoma Bacteriano , Genômica/métodos , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/transmissão , Interações Hospedeiro-Patógeno/imunologia , Humanos , Filogenia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , RNA Ribossômico 16S , Relação Estrutura-Atividade , Virulência , Fatores de Virulência/química , Fatores de Virulência/genética , Fatores de Virulência/imunologia
4.
PLoS Pathog ; 15(5): e1007730, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31048927

RESUMO

Enterococcus faecalis is an opportunistic pathogen with an intrinsically high resistance to lysozyme, a key effector of the innate immune system. This high level of resistance requires a complex network of transcriptional regulators and several genes (oatA, pgdA, dltA and sigV) acting synergistically to inhibit both the enzymatic and cationic antimicrobial peptide activities of lysozyme. We sought to identify novel genes modulating E. faecalis resistance to lysozyme. Random transposon mutagenesis carried out in the quadruple oatA/pgdA/dltA/sigV mutant led to the identification of several independent insertions clustered on the chromosome. These mutations were located in a locus referred to as the enterococcal polysaccharide antigen (EPA) variable region located downstream of the highly conserved epaA-epaR genes proposed to encode a core synthetic machinery. The epa variable region was previously proposed to be responsible for EPA decorations, but the role of this locus remains largely unknown. Here, we show that EPA decoration contributes to resistance towards charged antimicrobials and underpins virulence in the zebrafish model of infection by conferring resistance to phagocytosis. Collectively, our results indicate that the production of the EPA rhamnopolysaccharide backbone is not sufficient to promote E. faecalis infections and reveal an essential role of the modification of this surface polymer for enterococcal pathogenesis.


Assuntos
Antígenos de Superfície/imunologia , Enterococcus faecalis/patogenicidade , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/microbiologia , Muramidase/imunologia , Polissacarídeos/imunologia , Virulência , Animais , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Enterococcus faecalis/genética , Enterococcus faecalis/imunologia , Infecções por Bactérias Gram-Positivas/metabolismo , Muramidase/metabolismo , Mutagênese , Mutação , Polissacarídeos/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/imunologia , Peixe-Zebra/microbiologia
5.
Fish Shellfish Immunol ; 91: 264-274, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128294

RESUMO

Brown trout are polymorphic salmonid species, and it is of importance to investigate whether hybridization affects disease resistance. In this study, susceptibility of brown trout (Salmo trutta Abant, Anatolian, Black Sea, and Caspius) strains and their hybrids to Lactococcus garvieae and Yersinia ruckeri as well as their immune-related gene expression profiles were studied. Results indicated that reciprocal hybridization did not affect disease resistance in brown trout strains. Purebred Black Sea strain of brown trout was the most resistant group against Y. ruckeri, followed by other Black Sea strain hybrids. On the other hand, purebred Anatolian strain was the most resistant group to L. garvieae, followed by other Anatolian strain hybrids. Expression pattern of target genes differed in families, but the overall gene expression was comparatively high in Y. ruckeri infected families. Upregulations were mainly significant at 7 and 28 d post infection while marginal regulations were observed 8 h after infection. Disease resistance status of strains was supported by high expression of immune-related genes such as major histocompatibility complex class I (MHC-I), immunoglobulin light chain (IgL), and antioxidant- and hemoglobin-related gene expression. Therefore, our findings suggest that Black Sea and Anatolian strains could be used to develop fish stock that are resistant for yersiniosis and lactocaccosis, respectively.


Assuntos
Suscetibilidade a Doenças/veterinária , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Truta/genética , Truta/imunologia , Yersiniose/veterinária , Animais , Suscetibilidade a Doenças/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Hibridização Genética , Lactococcus/fisiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Transcriptoma , Yersiniose/imunologia , Yersinia ruckeri/fisiologia
6.
Fish Shellfish Immunol ; 90: 446-455, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31002928

RESUMO

Adiponectin (APN) is an important cytokine secreted by fat cells that is responsible for regulating numerous biological functions. However, the APN gene in lamprey and its precise function remain unidentified. In this study, the full-length cDNA sequence of L-APN was cloned, and it encoded a protein of 267 amino acid residues with a globular domain. The results of immunohistochemistry and FACS assays showed that APN protein was distributed in multiple tissues. L-APN expression in the supraneural body (SB) and leukocytes was differentially upregulated in response to Gram-negative bacteria, Gram-positive bacteria and poly (I:C). The expression levels of inflammatory cytokines were upregulated, and a proapoptotic effect was stimulated in SB cells treated with recombinant APN. Furthermore, L-APN could inhibit cell proliferation and arrest cell growth in the G1 phase. In summary, the APN protein from the lamprey plays an important role in inhibiting cell proliferation, inducing the production of inflammatory cytokines and promoting cell apoptosis, and it is also involved in immune responses and immune defenses. Our data provide insights into the evolutionary origin of the structure and function of APN gene.


Assuntos
Adiponectina/genética , Adiponectina/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lampreias/genética , Lampreias/imunologia , Adiponectina/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Citocinas/genética , Citocinas/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Inflamação/imunologia , Inflamação/veterinária , Filogenia , Poli I-C/farmacologia , Alinhamento de Sequência/veterinária
7.
Vet Microbiol ; 230: 202-211, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30827389

RESUMO

Aerococcus viridans, a firmicutes bacteria widespread in the environment, is increasingly isolated from humans and animals, especially cows with mastitis. However, its pathogenicity in the bovine mammary gland is unclear. The objective was to explore pathogenic potential of putative virulent and avirulent A. viridans in murine systemic and intramammary infection and mechanistically in cultured bovine mammary epithelial cells (bMECs). Virulence of 9 strains of A. viridans, isolated from subclinical cases of mastitis, was tested for their ability to kill mice when systemically inoculated. Two A. viridans strains, causing highest and lowest survival rate in mice, were selected further as putative avirulent and virulent strains, respectively. Staphylococcus aureus N305 was used as a positive control. After intramammary inoculation, the virulent strain survived and replicated in the murine mammary gland for 9 d, whereas the avirulent strain was eliminated within 3 d. The virulent strain induced a robust inflammatory reaction in the mammary gland, characterized by acute histopathological changes, increased myeloperoxidase activity and higher expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß) compared to the avirulent strain. The virulent strain produced CAMP factor and exhibited strong cytotoxic effects (LDH release) and adhering and invasive abilities in contact with bMECs. Adhesion and invasion of virulent strain to bMECs was further confirmed by scanning and transmission electron microscopy; there was severe damage, including cytomembrane disruption, swollen mitochondria and loss of organelles. In conclusion, the putative virulent strain of A. viridans activated a strong neutrophil-based inflammatory response in the mammary gland, attributed to its ability to adhere to and invade mammary epithelium.


Assuntos
Aerococcus/patogenicidade , Infecções por Bactérias Gram-Positivas/imunologia , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/microbiologia , Mastite/microbiologia , Animais , Aderência Bacteriana , Bovinos , Citocinas/imunologia , Modelos Animais de Doenças , Células Epiteliais/microbiologia , Feminino , Inflamação , Mastite/imunologia , Mastite Bovina/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Peroxidase/análise , Organismos Livres de Patógenos Específicos , Infecções Estafilocócicas , Virulência
8.
Immunity ; 50(4): 1069-1083.e8, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30926233

RESUMO

Skin conventional dendritic cells (cDCs) exist as two distinct subsets, cDC1s and cDC2s, which maintain the balance of immunity to pathogens and tolerance to self and microbiota. Here, we examined the roles of dermal cDC1s and cDC2s during bacterial infection, notably Propionibacterium acnes (P. acnes). cDC1s, but not cDC2s, regulated the magnitude of the immune response to P. acnes in the murine dermis by controlling neutrophil recruitment to the inflamed site and survival and function therein. Single-cell mRNA sequencing revealed that this regulation relied on secretion of the cytokine vascular endothelial growth factor α (VEGF-α) by a minor subset of activated EpCAM+CD59+Ly-6D+ cDC1s. Neutrophil recruitment by dermal cDC1s was also observed during S. aureus, bacillus Calmette-Guérin (BCG), or E. coli infection, as well as in a model of bacterial insult in human skin. Thus, skin cDC1s are essential regulators of the innate response in cutaneous immunity and have roles beyond classical antigen presentation.


Assuntos
Acne Vulgar/imunologia , Células Dendríticas/classificação , Infecções por Bactérias Gram-Positivas/imunologia , Infiltração de Neutrófilos/imunologia , Fator A de Crescimento do Endotélio Vascular/imunologia , Acne Vulgar/microbiologia , Animais , Apresentação do Antígeno , Quimiotaxia de Leucócito/imunologia , Células Dendríticas/imunologia , Orelha Externa , Regulação da Expressão Gênica , Ontologia Genética , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Injeções Intradérmicas , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Propionibacterium acnes , RNA Mensageiro/biossíntese , Análise de Célula Única , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética
9.
Fish Shellfish Immunol ; 89: 43-51, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30890434

RESUMO

Complement factor D (Df) is a serine protease, which can activate the alternative pathway by cleaving complement factor B, and involves in the innate defense against pathogens infection in teleost. In this study, we cloned, characterized the Df gene from blunt snout bream (Megalobrama amblycephala) (Mamdf), and examined its expression pattern and antimicrobial activity. The open reading frame (ORF) of Mamdf was 753 bp, encoding 250 amino acids with a molecular mass of 27.2 kDa. Mamdf consisted of a single serine protease trypsin superfamily domain, 3 substrate binding sites and 3 active sites, but no potential N-glycosylation site. Pairwise alignment showed that Mamdf shared the highest identity (94%) with grass carp (Ctenopharyngodon idellus). Phylogenetic analysis indicated that Mamdf and other vertebrate Df had a common ancestral origin. Mamdf structured with 4 introns and 5 exons. The Mamdf mRNA expressed relatively high at the intestine appearance stage during early development and constitutively expressed in various tissues with the highest expression in the kidney in healthy adults. After challenged with Aeromonas hydrophila, significant changes of Mamdf at both mRNA and protein levels in the kidney, spleen, liver and head-kidney were observed. The recombinant Mamdf protein showed antimicrobial activity against both gram-positive bacteria and gram-negative bacteria. The above results suggested the immune function of Mamdf, and would benefit further detailed Df function research in the immune process in teleost.


Assuntos
Fator D do Complemento/genética , Fator D do Complemento/imunologia , Cyprinidae/genética , Cyprinidae/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Animais , Fator D do Complemento/química , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Filogenia , Distribuição Aleatória , Alinhamento de Sequência/veterinária
10.
Fish Shellfish Immunol ; 87: 401-409, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30711494

RESUMO

In this study, therapeutic effects of aqueous methanolic extracts of beard lichen (Usnea barbata) against Lactococcus garvieae (ATCC 43921) in rainbow trout (Onchorhynchus mykiss) were investigated. Six different experimental groups [0 mg/100 µL (Control), 4 mg/100 µL, 8 mg/100 µL, 12 mg/100 µL, 6 mg/100 µL florfenicol (positive control), 6 mg/100 µL erythromycin (positive control)] were set up to determine effects of lichen extract on immune responses and survival rate. In the study, superoxide radical production was increased in fish treated with 12 mg beard lichen extract, florfenicol and erythromycin compared to that of control (P < 0.05). Lysozyme activity was generally decreased (P < 0.05) or no differences were observed in all experimental groups compared to that of control (P > 0.05). Myeloperoxidase was significantly increased in all antibiotic treated groups. No differences were observed in liver histology of experimental groups compared to control. Cytokine gene expressions were elevated in all experimental groups compared to that of control (P < 0.05), except IL-1ß expression at 10th day sampling time. Other immune related genes (IL-8, TGF- ß, IL-12 Beta, TNFα1, IL-10, COX-2, IL-6, TLR5, C3, IGM, MHC-II, iNOS, IgT, IFN1, IFN2, IFN reg) were also elevated in all experimental groups compared to that of control group. The survival rates obtained in 4 mg beard lichen treated group, 8 mg beard lichen treated group and erythromycin treated group were 73.08, 65.38 and 80.77% respectively. Our results suggest that beard lichen methanolic extract could be an effective therapeutic agent to be used against L. garvieae infection in rainbow trout at the dose of 4 mg/17.41 ±â€¯0.3 g body weight/day.


Assuntos
Doenças dos Peixes/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus/efeitos dos fármacos , Oncorhynchus mykiss , Usnea/química , Animais , Relação Dose-Resposta a Droga , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/imunologia , Lactococcus/fisiologia
11.
Dev Comp Immunol ; 95: 19-27, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30708026

RESUMO

The miR-317 has been revealed to involve in the reproductive response and the larval ovary morphogenesis of Drosophila. However, whether the miR-317 can also regulate Drosophila innate immune responses, which remains unclear to date. Here we have verified that miR-317 can directly target the 3'UTR of Dif-Rc to down-regulate the expression levels of AMP Drs to negatively control Drosophila Toll immune response in vivo and vitro. Specially, the Dif is an important transcription factor of Toll pathway with four transcripts (Dif-Ra, Dif-Rb, Dif-Rc and Dif-Rd). Our results show that miR-317 only targets to Dif-Rc, but not Dif-Ra/b/d, implying that miRNAs can regulate different isoforms of an alternative splicing gene to fine tune immune responses and maintain homeostasis in post-transcriptional level. Furthermore, we have demonstrated that the miR-317 sponge can restore the expression levels of Drs and Dif-Rc at mRNA and protein levels. Remarkably, during Gram-positive bacterial infection, the overexpressed miR-317 flies have poor survival outcome, whereas the knockout miR-317 flies have favorable survival compared to the control group, respectively, suggesting that the miR-317 might play a key role in Drosophila survival. Taken together, our current works not only reveal an innate immune function and a novel regulation pattern of miR-317, but also provide a new insight into the underlying molecular mechanisms of immunity disorder influencing on Drosophila survival.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , MicroRNAs/metabolismo , Receptores Toll-Like/metabolismo , Fatores de Transcrição/genética , Processamento Alternativo , Animais , Animais Geneticamente Modificados , Proteínas de Ligação a DNA/imunologia , Proteínas de Drosophila/imunologia , Drosophila melanogaster/microbiologia , Regulação da Expressão Gênica/imunologia , Infecções por Bactérias Gram-Positivas/mortalidade , Imunidade Inata/genética , Masculino , MicroRNAs/genética , MicroRNAs/imunologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptores Toll-Like/imunologia , Fatores de Transcrição/imunologia
12.
Fish Shellfish Immunol ; 88: 293-300, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30807857

RESUMO

A vaccine against streptococcosis, lactococcosis and enterococcosis in tilapia was formulated, ME-VAC Aqua Strept, as a polyvalent inactivated vaccine containing Streptococcus agalactiae, S. iniae, Lactococcus garvieae and Enterococcus faecalis along with a nano-particulate adjuvant. Use of ME-VAC Aqua Strept by injection or immersion resulted in an improved non-specific and adaptive immunity of broodstock and offspring. Intra-peritoneal vaccination of tilapia broodstock increased the total leukocyte count, phagocytosis, lysozyme activity, antibody titer, number of seeds/vaccinated broodstock, seeds quality and survival rates. Also, immersion mass vaccination of tilapia larvae provided a long period of protection up to three months, with a relative percent of survivability (RPS) not less than 60% at this time. To our knowledge, this vaccine may be the first to offer a combined protection against streptococcosis, lactococcosis and enterococcosis in tilapia. The results support the use of this vaccine as an effective tool for disease control and well-being of fish.


Assuntos
Vacinas Bacterianas/imunologia , Ciclídeos/imunologia , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Animais , Aquicultura , Vacinas Bacterianas/administração & dosagem , Ciclídeos/microbiologia , Enterococcus faecalis/imunologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Imersão , Injeções Intraperitoneais/veterinária , Lactococcus/imunologia , Larva/imunologia , Larva/microbiologia , Streptococcus agalactiae/imunologia , Streptococcus iniae/imunologia , Análise de Sobrevida , Vacinação/veterinária
14.
PLoS Pathog ; 15(1): e1007504, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30633769

RESUMO

Non-coding RNAs have important roles in regulating physiology, including immunity. Here, we performed transcriptome profiling of immune-responsive genes in Drosophila melanogaster during a Gram-positive bacterial infection, concentrating on long non-coding RNA (lncRNA) genes. The gene most highly induced by a Micrococcus luteus infection was CR44404, named Induced by Infection (lincRNA-IBIN). lincRNA-IBIN is induced by both Gram-positive and Gram-negative bacteria in Drosophila adults and parasitoid wasp Leptopilina boulardi in Drosophila larvae, as well as by the activation of the Toll or the Imd pathway in unchallenged flies. We show that upon infection, lincRNA-IBIN is expressed in the fat body, in hemocytes and in the gut, and its expression is regulated by NF-κB signaling and the chromatin modeling brahma complex. In the fat body, overexpression of lincRNA-IBIN affected the expression of Toll pathway -mediated genes. Notably, overexpression of lincRNA-IBIN in unchallenged flies elevated sugar levels in the hemolymph by enhancing the expression of genes important for glucose retrieval. These data show that lncRNA genes play a role in Drosophila immunity and indicate that lincRNA-IBIN acts as a link between innate immune responses and metabolism.


Assuntos
Infecções por Bactérias Gram-Positivas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/imunologia , Animais , Montagem e Desmontagem da Cromatina , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/imunologia , Drosophila melanogaster/microbiologia , Bactérias Gram-Negativas/imunologia , Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Hemolinfa/metabolismo , Imunidade Inata/genética , NF-kappa B/metabolismo , Transdução de Sinais , Transcriptoma/genética , Vespas/genética , Vespas/imunologia
15.
Dev Comp Immunol ; 90: 41-46, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30179632

RESUMO

Lumbricin and its orthologue antimicrobial peptides were typically isolated from annelids. In this report, mRNA for lumbricin and -serendipitously- a novel lumbricin-related mRNA sequence were identified in Eisenia andrei earthworms. The determined mRNA sequences of E. andrei lumbricin and lumbricin-related peptide consist of 477 and 575 nucleotides. The precursors of proline-rich E. andrei lumbricin and the related peptide contain 63 and 59 amino acids, respectively. Phylogenetic analysis indicated close relationship with other annelid lumbricins. Highest expression of both mRNAs appeared in the proximal part of the intestine (pharynx, gizzard), while other tested organs had moderate (body wall, midgut, ovary, metanephridium, seminal vesicles, ventral nerve cord) or low (coelomocytes) levels. During ontogenesis their expression revealed continuous increase in embryos. Following 48 h of in vivo Gram-positive bacteria challenge both mRNAs were significantly elevated in coelomocytes, while Gram-negative bacteria or zymosan stimulation had no detectable effects.


Assuntos
Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Proteínas de Helminto/genética , Intestinos/fisiologia , Oligoquetos/imunologia , Peptídeos/genética , Animais , Anti-Infecciosos/metabolismo , Clonagem Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Helminto/metabolismo , Imunidade Inata , Oligoquetos/genética , Oligoquetos/microbiologia , Peptídeos/metabolismo , Filogenia , Transcriptoma
16.
Front Immunol ; 9: 2768, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581431

RESUMO

Adequate perception of immunologically important pathogen-associated molecular patterns like lipopolysaccharide and bacterial lipoproteins is essential for efficient innate and adaptive immune responses. In the context of Gram-negative infection, bactericidal/permeability-increasing protein (BPI) neutralizes endotoxic activity of lipopolysaccharides, and thus prohibits hyperactivation. So far, no immunological function of BPI has been described in Gram-positive infections. Here, we show a significant elevation of BPI in Gram-positive meningitis and, surprisingly, a positive correlation between BPI and pro-inflammatory markers like TNFα. To clarify the underlying mechanisms, we identify BPI ligands of Gram-positive origin, specifically bacterial lipopeptides and lipoteichoic acids, and determine essential structural motifs for this interaction. Importantly, the interaction of BPI with these newly defined ligands significantly enhances the immune response in peripheral blood mononuclear cells (PBMCs) mediated by Gram-positive bacteria, and thereby ensures their sensitive perception. In conclusion, we define BPI as an immune enhancing pattern recognition molecule in Gram-positive infections.


Assuntos
Peptídeos Catiônicos Antimicrobianos/imunologia , Proteínas de Bactérias/imunologia , Proteínas Sanguíneas/imunologia , Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Lipoproteínas/imunologia , Meningites Bacterianas/imunologia , Infecções por Bactérias Gram-Positivas/patologia , Células HEK293 , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Lipopeptídeos/imunologia , Lipopolissacarídeos/imunologia , Masculino , Meningites Bacterianas/patologia , Ácidos Teicoicos/imunologia , Fator de Necrose Tumoral alfa/imunologia
17.
Yakugaku Zasshi ; 138(10): 1249-1253, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30270267

RESUMO

 Whereas granulopoiesis during Gram-negative bacterial infection is accelerated through activation of toll-like receptor 4 (TLR4), it has not been elucidated whether Gram-positive bacterial infection can stimulate granulopoiesis. Using the well-known TLR2 agonist peptidoglycan (PGN), it was shown that neutrophils in bone marrow and spleen and plasma granulocyte colony-stimulating factor were increased in mice that had received intraperitoneal administration of PGN. Incorporation of bromodeoxyuridine into bone marrow neutrophils increased in mice administered PGN, demonstrating that PGN promotes granulopoiesis. These results illustrate that bacterial recognition by TLR2 facilitates granulopoiesis during Gram-positive bacterial infection. Thus, granulopoiesis is accelerated to suppress bacterial infection, but some bacteria can still cause severe infections. Clostridium perfringens is a Gram-positive, anaerobic pathogenic bacterium and causes life-threatening gas gangrene in humans. Of the many toxins produced by C. perfringens, α-toxin is known to be a major virulence factor during infection. Recently, it has been revealed that C. perfringens α-toxin impairs the innate immune system by inhibiting neutrophil differentiation, which is crucial for the pathogenesis of C. perfringens. Moreover, the toxin also attenuates erythropoiesis, which would cause severe anemia in clinical settings. The findings provide new insight to understand how hosts strengthen innate immunity to fight pathogenic bacteria and how they evade the hosts' immune systems.


Assuntos
Toxinas Bacterianas/toxicidade , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Neutropenia/imunologia , Peptidoglicano/farmacologia , Animais , Bromodesoxiuridina/metabolismo , Proteínas de Ligação ao Cálcio/toxicidade , Diferenciação Celular/efeitos dos fármacos , Clostridium perfringens/patogenicidade , Gangrena/microbiologia , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Camundongos , Neutropenia/etiologia , Neutropenia/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Peptidoglicano/administração & dosagem , Receptor 2 Toll-Like/agonistas , Receptor 4 Toll-Like/imunologia , Fosfolipases Tipo C/toxicidade
18.
Vet Immunol Immunopathol ; 203: 78-87, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30143242

RESUMO

Dendritic cells (DC) are crucial for maintaining intestinal homeostasis and generating proper immune responses to bacteria occurring in the gut. Microbial stimuli can be recognized by intracellular receptors called inflammasomes, e.g., nucleotide oligomerization domain (NOD)-like receptor protein 3 (NLRP3). The aim of the present study was to unravel the inflammasome response of porcine monocyte-derived DC (MoDC). We investigated the capacity of probiotic Enterococcus faecium NCIMB 10415 (E. faecium) and enterotoxigenic Escherichia coli (ETEC) to elicit inflammasome activation. Since inflammasome activation normally requires a two-step process, MoDC were initially incubated with lipopolysaccharide (LPS) in order to prime cells. Primed and unprimed cells were then stimulated with the aforementioned bacterial strains. We also assessed whether preincubation with the probiotic prior to ETEC infection modified the immune response via the inflammasome pathway. Phenotypical analysis by flow cytometry showed that monocytes and MoDC expressed the surface markers CD14, CD16, and CD1 continuously, whereas swine leucocyte antigen (SLA) II was upregulated during differentiation. Following LPS priming, NLRP3, interleukin (IL)-1ß and IL-18 mRNA expression, and IL-1ß protein release increased. In unprimed cells, ETEC upregulated the expression of inflammasome components at later time points than in LPS-primed MoDC. Preincubation with the probiotic did not influence NLRP3 inflammasome activation in comparison with cells infected with ETEC alone. We conclude that ETEC, but not E. faecium, was able to stimulate inflammasome components in porcine MoDC. The present experimental conditions revealed no NLRP3 inflammasome-dependent protective effects of E. faecium during a pathogenic ETEC challenge.


Assuntos
Células Dendríticas/imunologia , Enterococcus faecium/imunologia , Escherichia coli Enterotoxigênica/imunologia , Inflamassomos/imunologia , Probióticos/farmacologia , Animais , Células Dendríticas/microbiologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/veterinária , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Suínos/imunologia , Suínos/microbiologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia
19.
Fish Shellfish Immunol ; 80: 141-147, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29879509

RESUMO

Cathepsin F is a unique papain cysteine proteinase with highly conserved structures: catalytic triad and a cystatin domain contained in the elongated N-terminal pro-region. It has been reported that cathepsin F is associated with the establishment of innate immune in several vertebrate including fish in aquaculture, but not known in bivalves. In this study, we firstly identified and characterized cathepsin F in the Yesso scallop (Patinopecten yessoensis). The protein structural and phylogenetic analyses were then conducted to determine its identity and evolutionary position. We've also investigated the expression levels of cathepsin F gene at different embryonic developmental stages, in healthy adult tissues and especially in the hemocytes and hepatopancreas after Gram-positive (Micrococcus luteus) and negative (Vibrio anguillarum) challenges using quantitative real-time PCR (qPCR). Cathepsin F was significantly up-regulated 3 h after infection of V. anguillarum in hemocytes, suggesting its participation in immune response. Our findings have provided strong evidence that cathepsin F may be a good target for enhancing the immune activity in Yesso scallop.


Assuntos
Catepsina F , Infecções por Bactérias Gram-Positivas/imunologia , Pectinidae/genética , Pectinidae/imunologia , Vibrioses/imunologia , Sequência de Aminoácidos , Animais , Catepsina F/química , Catepsina F/genética , Catepsina F/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Hemócitos/imunologia , Hepatopâncreas/imunologia , Micrococcus luteus , Filogenia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , RNA Mensageiro/genética , Vibrio , Vibrioses/veterinária
20.
Fish Shellfish Immunol ; 79: 340-350, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29803666

RESUMO

C-type lectin (CTL) is an immune receptor and is received extensive attention of its important roles in immune response and immune escape. Some CTL, such as CTL4, has been well characterized in human and several other mammals, but much less documentation exists about the immunological function of CTL4 in lower vertebrates. In the present study, a C-type lectin domain family 4 member, SsCTL4, which is also high homology with CD209 antigen-like protein, from the teleost fish black rockfish (Sebastes schlegelii) was identified and examined at expression and functional levels. The open reading frame of SsCTL4 is 765 bp, and the deduced amino acid sequence of SsCTL4 shares 78%-84% overall identities with the C-type lectin of several fish species. In silico analysis identified several conserved C-type lectin features, including a carbohydrate-recognition domain and four disulfide bond-forming cysteine residues. Expression of SsCTL4 occurred in multiple tissues and was upregulated during bacterial and viral infection. Recombinant SsCTL4 (rSsCTL4) exhibited apparent binding activities against bacteria (Edwardsiella tarda and Vibrio anguillarum) and virus (infectious spleen and kidney necrosis virus, ISKNV). rSsCTL4 was able to agglutinate the Gram-negative and Gram-positive bacteria in a Ca2+-dependent manner. The agglutinating ability of rSsCTL4 was abolished in the absence of calcium or presence of mannose. rSsCTL4 also increased macrophage bactericidal activity. In the presence of rSsCTL4, fish exhibited enhanced resistance against bacterial infection but increased susceptibility to viral infections. Collectively, these results indicate that SsCTL4 serves as a pattern recognition receptor that not only promotes bactericidal activity, but may also serve as targets for virus manipulation of host defense system.


Assuntos
Doenças dos Peixes/imunologia , Peixes/genética , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Aglutinação , Sequência de Aminoácidos , Animais , Sequência de Bases , Infecções por Vírus de DNA/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Iridoviridae/fisiologia , Lectinas Tipo C/química , Filogenia , Distribuição Aleatória , Alinhamento de Sequência/veterinária
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