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1.
Front Immunol ; 12: 690234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220849

RESUMO

As an intermediate substance of the tricarboxylic acid cycle and a precursor substance of glutamic acid synthesis, the effect of alpha-ketoglutarate on growth and protein synthesis has been extensively studied. However, its prevention and treatment of pathogenic bacteria and its mechanism have not yet been noticed. To evaluate the effects of alpha-ketoglutarate on intestinal antioxidant capacity and immune response of Songpu mirror carp, a total of 360 fish with an average initial weight of 6.54 ± 0.08 g were fed diets containing alpha-ketoglutarate with 1% for 8 weeks. At the end of the feeding trial, the fish were challenged with Aeromonas hydrophila for 2 weeks. The results indicated that alpha-ketoglutarate supplementation significantly increased the survival rate of carp after infection with Aeromonas hydrophila (P < 0.05), and the contents of immune digestion enzymes including lysozyme, alkaline phosphatase and the concentration of complement C4 were markedly enhanced after alpha-ketoglutarate supplementation (P < 0.05). Also, appropriate alpha-ketoglutarate increased the activities of total antioxidant capacity and catalase and prevented the up-regulation in the mRNA expression levels of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1ß, interleukin-6, and interleukin-8 (P < 0.05). Furthermore, the mRNA expression levels of toll-like receptor 4 (TLR4), and nuclear factor kappa-B (NF-κB) were strikingly increased after infection with Aeromonas hydrophila (P < 0.05), while the TLR4 was strikingly decreased with alpha-ketoglutarate supplementation (P < 0.05). Moreover, the mRNA expression levels of tight junctions including claudin-1, claudin-3, claudin-7, claudin-11 and myosin light chain kinases (MLCK) were upregulated after alpha-ketoglutarate supplementation (P < 0.05). In summary, the appropriate alpha-ketoglutarate supplementation could increase survival rate, strengthen the intestinal enzyme immunosuppressive activities, antioxidant capacities and alleviate the intestinal inflammation, thereby promoting the intestinal immune responses and barrier functions of Songpu mirror carp via activating TLR4/MyD88/NF-κB and MLCK signaling pathways after infection with Aeromonas hydrophila.


Assuntos
Aeromonas hydrophila/patogenicidade , Antioxidantes/metabolismo , Carpas/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Imunidade Inata/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Ácidos Cetoglutáricos/farmacologia , Aeromonas hydrophila/imunologia , Ração Animal , Animais , Carpas/crescimento & desenvolvimento , Carpas/imunologia , Carpas/metabolismo , Suplementos Nutricionais , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Interações Hospedeiro-Patógeno , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
2.
Front Immunol ; 12: 633324, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262558

RESUMO

In the process of microbial invasion, the inflammation reaction is induced to eliminate the pathogen. However, un-controlled or un-resolved inflammation can lead to tissue damage and death of the host. MicroRNAs (miRNAs) are the signaling regulators that prevent the uncontrolled progress of an inflammatory response. Our previous work strongly indicated that miR-142a-3p is related to the immune regulation in grass carp. In the present study, we found that the expression of miR-142a-3p was down-regulated after infection by Aeromonas hydrophila. tnfaip2 and glut3 were confirmed as be the target genes of miR-142a-3p, which were confirmed by expression correlation analysis, gene overexpression, and dual luciferase reporter assay. The miR-142a-3p can reduce cell viability and stimulate cell apoptosis by targeting tnfaip2 and glut3. In addition, miR-142a-3p also regulates macrophage polarization induced by A. hydrophila. Our results suggest that miR-142a-3p has multiple functions in host antibacterial immune response. Our research provides further understanding of the molecular mechanisms between miRNAs and their target genes, and provides a new insights for the development of pro-resolution strategies for the treatment of complex inflammatory diseases in fish.


Assuntos
Apoptose/genética , Carpas/genética , Citocinas/genética , Transportador de Glucose Tipo 3/genética , Infecções por Bactérias Gram-Negativas/veterinária , Macrófagos/fisiologia , MicroRNAs/genética , Aeromonas hydrophila/imunologia , Aeromonas hydrophila/patogenicidade , Animais , Carpas/imunologia , Carpas/microbiologia , Células Cultivadas , Citocinas/classificação , Infecções por Bactérias Gram-Negativas/imunologia , Inflamação/imunologia , Rim/citologia , Rim/microbiologia , Macrófagos do Fígado/microbiologia , Ativação de Macrófagos , MicroRNAs/classificação , Transdução de Sinais
3.
Mol Immunol ; 137: 114-123, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34242920

RESUMO

Toll-like receptors (TLRs) represent first line of host defence against microbes. Amongst different TLRs, TLR22 is exclusively expressed in non-mammalian vertebrates, including fish. The precise role of TLR22 in fish-immunity remains abstruse. Herein, we used headkidney macrophages (HKM) from Clarias gariepinus and deciphered its role in fish-immunity. Highest tlr22 expression was observed in the immunocompetent organ - headkidney; nonetheless expression in other tissues suggests its possible involvement in non-immune sites also. Aeromonas hydrophila infection up-regulates tlr22 expression in HKM. Our RNAi based study suggested TLR22 restricts intracellular survival of A. hydrophila. Inhibitor and RNAi studies further implicated TLR22 induces pro-inflammatory cytokines TNF-α and IL-1ß. We observed heightened caspase-1 activity and our results suggest the role of TLR22 in activating TNF-α/caspase-1/IL-1ß cascade leading to caspase-3 mediated apoptosis of A. hydrophila-infected HKM. We conclude, TLR22 plays critical role in immune-surveillance and triggers pro-inflammatory cytokines leading to caspase mediated HKM apoptosis and pathogen clearance.


Assuntos
Aeromonas hydrophila/imunologia , Apoptose/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Inflamação/imunologia , Macrófagos/imunologia , Receptores Toll-Like/imunologia , Animais , Caspases/imunologia , Peixes-Gato/imunologia , Peixes-Gato/microbiologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Rim Cefálico/imunologia , Rim Cefálico/microbiologia , Inflamação/microbiologia , Interleucina-1beta/imunologia , Macrófagos/microbiologia , Fator de Necrose Tumoral alfa/imunologia
4.
Mol Immunol ; 137: 145-154, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34247100

RESUMO

Previous studies have found that the expression level of Megalobrama amblycephala intelectin (MaINTL) increased significantly post Aeromonas hydrophila infection, and recombinant MaINTL (rMaINTL) protein could activate macrophages and enhance the phagocytosis and killing activity of macrophages. In order to reveal the immune regulatory mechanisms of MaINTL, primary M. amblycephala macrophages were treated with endotoxin-removed rMaINTL and GST-tag proteins, then total RNA were extracted and used for comparative Digital Gene Expression Profiling (DGE). 1247 differentially expressed genes were identified by comparing rMaINTL and GST-tag treated macrophage groups, including 482 up-regulated unigenes and 765 down-regulated unigenes. In addition, eleven randomly selected differentially expressed genes were verified by qRT-PCR, and most of them shared the similar expression patterns as that of DGE results. GO enrichment revealed that the differentially expressed genes were mainly concentrated in the membrane part and cytoskeleton of cellular component, the binding and signal transducer activity of molecular function, the cellular process, regulation of biological process, signaling and localization of biological process, most of which might related with the phagocytosis and killing activity of macrophages. KEGG analysis revealed the activation and involvement of differentially expressed genes in immune related pathways, such as Tumor necrosis factor (TNF) signaling pathway, Interleukin 17 (IL-17) signaling pathway, Toll-like receptor signaling pathway, and NOD like receptor signaling pathway, etc. In these pathways, TNF-ɑ, Activator protein-1 (AP-1), Myeloid differentiation primary response protein MyD88 (MyD88), NF-kappa-B inhibitor alpha (ikBɑ) and other key signaling factors were significantly up-regulated. These results will be helpful to clarify the immune regulatory mechanisms of fish intelectin on macrophages, thus providing a theoretical basis for the prevention and control of fish bacterial diseases.


Assuntos
Aeromonas hydrophila/imunologia , Cyprinidae/imunologia , Cyprinidae/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Macrófagos/imunologia , Fagocitose/imunologia , Animais , Regulação para Baixo/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/métodos , Infecções por Bactérias Gram-Negativas/microbiologia , Fatores Imunológicos/imunologia , Macrófagos/microbiologia , Transdução de Sinais/imunologia , Transcriptoma/imunologia , Fator de Necrose Tumoral alfa/imunologia , Regulação para Cima/imunologia
5.
Fish Shellfish Immunol ; 114: 132-141, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33932598

RESUMO

Biofilm vaccine has been recognised as one of the successful strategy to reduce the Aeromonas hydrophila infection in fish. But, the vaccine contains the protective and non-protective proteins, which may lead to show altered heterologous adaptive immunity response. Moreover, cross protection and effectiveness of previously developed biofilm vaccine was not tested against different geographical A. hydrophila isolates. Therefore, in the present study, whole-cell A. hydrophila biofilm vaccine was evaluated in rohu, vaccinated group showed increased antibody titer and protection against the different geographical A. hydrophila isolates namely KAH1 and AAH2 with 78.9% and 84.2% relative percentage survival, respectively. In addition, by using the immune sera of biofilm vaccinated group, a total of six protective proteins were detected using western blot assay. Further, the same proteins were identified by nano LC-MS/MS method, a total of fourteen candidate proteins showing the immunogenic property including highly expressed OMP's tolC, bamA, lamb, AH4AK4_2542, AHGSH82_029580 were identified as potential vaccine candidates. The STRING analysis revealed that, top candidate proteins identified may potentially interact with other intracellular proteins; involved in ribosomal and (tricarboxylic acid) TCA pathway. Importantly, all the selected vaccine candidate proteins contain the B-cell epitope region. Finally, the present study concludes that, whole-cell A. hydrophila biofilm vaccine able to protect the fish against the different geographical A. hydrophila isolates. Further, through reverse vaccinology approach, a total of fourteen proteins were identified as potential vaccine candidates against A. hydrophila pathogen.


Assuntos
Aeromonas hydrophila/fisiologia , Biofilmes/crescimento & desenvolvimento , Cyprinidae , Doenças dos Peixes/prevenção & controle , Aeromonas hydrophila/imunologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vacinas Bacterianas , Cromatografia Líquida/métodos , Epitopos de Linfócito B , Doenças dos Peixes/microbiologia , Nanotecnologia , Espectrometria de Massas em Tandem , Vacinologia/métodos
6.
J Immunol ; 206(9): 2001-2014, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33858963

RESUMO

IgZ or its equivalent IgT is a newly discovered teleost specific Ig class that is highly specialized in mucosal immunity. However, whether this IgZ/IgT class participates in other biological processes remains unclear. In this study, we unexpectedly discovered that IgZ is highly expressed in zebrafish ovary, accumulates in unfertilized eggs, and is transmitted to offspring from eggs to zygotes. Maternally transferred IgZ in zygotes is found at the outer and inner layers of chorion, perivitelline space, periphery of embryo body, and yolk, providing different lines of defense against pathogen infection. A considerable number of IgZ+ B cells are found in ovarian connective tissues distributed between eggs. Moreover, pIgR, the transporter of IgZ, is also expressed in the ovary and colocalizes with IgZ in the zona radiata of eggs. Thus, IgZ is possibly secreted by ovarian IgZ+ B cells and transported to eggs through association with pIgR in a paracrine manner. Maternal IgZ in zygotes showed a broad bacteriostatic activity to different microbes examined, and this reactivity can be manipulated by orchestrating desired bacteria in water where parent fish live or immunizing the parent fish through vaccination. These observations suggest that maternal IgZ may represent a group of polyclonal Abs, providing protection against various environmental microbes encountered by a parent fish that were potentially high risk to offspring. To our knowledge, our findings provide novel insights into a previously unrecognized functional role of IgZ/IgT Ig in the maternal transfer of immunity in fish, greatly enriching current knowledge about this ancient Ig class.


Assuntos
Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Isotipos de Imunoglobulinas/imunologia , Proteínas de Peixe-Zebra/imunologia , Peixe-Zebra/imunologia , Aeromonas hydrophila/imunologia , Aeromonas hydrophila/fisiologia , Animais , Resistência à Doença/genética , Embrião não Mamífero/embriologia , Embrião não Mamífero/imunologia , Embrião não Mamífero/microbiologia , Feminino , Doenças dos Peixes/microbiologia , Expressão Gênica/imunologia , Interações Hospedeiro-Patógeno/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Isotipos de Imunoglobulinas/genética , Isotipos de Imunoglobulinas/metabolismo , Masculino , Herança Materna/genética , Herança Materna/imunologia , Vibrio/classificação , Vibrio/imunologia , Vibrio/fisiologia , Peixe-Zebra/genética , Peixe-Zebra/microbiologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Zigoto/imunologia , Zigoto/metabolismo , Zigoto/microbiologia
7.
BMC Vet Res ; 17(1): 159, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853603

RESUMO

BACKGROUND: Immunoglobulins (Igs) distributed among systemic immune tissues and mucosal immune tissues play important roles in protecting teleosts from infections in the pathogen-rich aquatic environment. Teleost IgZ/IgT subclasses with different tissue expression patterns may have different immune functions. RESULTS: In the present study, a novel secreted IgZ heavy chain gene was cloned and characterized in common carp (Cyprinus carpio). This gene exhibited a different tissue-specific expression profile than the reported genes IgZ1 and IgZ2. The obtained IgZ-like subclass gene designated CcIgZ3, had a complete open reading frame contained 1650 bp encoding a protein of 549 amino acid residues. Phylogenetic analysis revealed that CcIgZ3 was grouped with carp IgZ2 and was in the same branch as IgZ/IgT genes of other teleosts. Basal expression detection of the immunoglobulin heavy chain (IgH) in healthy adult common carp showed that CcIgZ3 transcripts were widely expressed in systemic immune tissues and mucosal-associated lymphoid tissues. CcIgZ3 was expressed at the highest levels in the head kidneys, gills, and gonads, followed by the spleen, hindgut, oral epithelium, liver, brain, muscle, foregut, and blood; it was expressed at a very low level in the skin. The transcript expression of CcIgZ3 in leukocytes isolated from peripheral blood cells was significantly higher than that in leukocytes isolated from the spleen. Different groups of common carp were infected with Aeromonas hydrophila via intraperitoneal injection or immersion. RT-qPCR analysis demonstrated that significant differences in CcIgZ3 mRNA levels existed between the immersion and injection groups in all the examined tissues, including the head kidney, spleen, liver, and hindgut; in particular, the CcIgZ3 mRNA level in the hindgut was higher in the immersion group than in the injection group. The different routes of A. hydrophila exposure in common carp had milder effects on the IgM response than on the CcIgZ3 response. Further study of the relative expression of the IgH gene during the development of common carp showed that the tissue-specific expression profile of CcIgZ3 was very different from those of other genes. RT-qPCR analysis demonstrated that the CcIgZ3 mRNA level increased gradually in common carp during the early larval development stage from 1 day post fertilization (dpf) to 31 dpf with a dynamic tendency similar to those of IgZ1 and IgZ2, and IgM was the dominant Ig with obviously elevated abundance. Analyses of the tissue-specific expression of IgHs in common carp at 65 dpf showed that CcIgZ3 was expressed at mucosal sites, including both the hindgut and gill; in contrast, IgZ1 was preferentially expressed in the hindgut, and IgZ2 was preferentially expressed in the gill. In addition to RT-qPCR analysis, in situ hybridization was performed to detect CcIgZ3-expressing cells and IgM-expressing cells. The results showed that CcIgZ3 and IgM transcripts were detectable in the spleens, gills, and hindguts of common carp at 65 dpf. CONCLUSIONS: These results reveal that CcIgZ3 gene transcripts are expressed in common carp during developmental stage not only in systemic tissues but also in mucosal tissues. CcIgZ3 expression can be induced in immune tissues by A. hydrophila challenge via immersion and intraperitoneal injection with significantly different expression profiles, which indicates that CcIgZ3 is involved in the antimicrobial immune response and might play an important role in gut mucosal immunity.


Assuntos
Carpas/imunologia , Doenças dos Peixes/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Aeromonas hydrophila/imunologia , Animais , Carpas/crescimento & desenvolvimento , Clonagem Molecular , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Cadeias Pesadas de Imunoglobulinas/química , Larva/imunologia , Filogenia , Análise de Sequência de Proteína
8.
Pak J Biol Sci ; 24(2): 199-206, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33683049

RESUMO

BACKGROUND AND OBJECTIVE: Leek (Allium ampeloprasum) is one of the most commonly used herbal foods all over the world. This study was conducted to evaluate the protective effect of leek extract on catfish experimentally challenged with Aeromonas hydrophila, a problematic bacterial pathogen that affects various freshwater fish species. MATERIALS AND METHODS: Aeromonas hydrophila was isolated and identified from catfish showing clinical signs of septicemia. The in vitro activity of leek extract to control the growth of Aeromonas hydrophila was investigated. In the in vivo experiment, about 240 adult catfish (Clarias gariepinus) were fed three different leek extract concentrations (10, 25 and 50 mg kg-1 body weight) for 1 month. Later on, a challenge study was conducted using an identified A. hydrophila strain. Morbidity and mortality were recorded throughout one week post-challenge. Furthermore, the effect of leek extract on some immune-related genes was investigated. RESULTS: Under the in vitro testing, a significant increase (10 and 13 mm) in the inhibition zone was recorded in wells treated with 25 and 50 mg L-1 leak extract, respectively. A significant reduction in fish mortalities was reported in all leek extract treated groups compared to the control group which was given water. TLR1 gene expression was upregulated in fish treated with leek extract while TNFα gene expression was down-regulated. CONCLUSION: Overall, results suggested that the leek extract has immunostimulating effects that can help control bacterial infections in catfish and probably other fish species.


Assuntos
Adjuvantes Imunológicos/farmacologia , Aeromonas hydrophila/efeitos dos fármacos , Antibacterianos/farmacologia , Peixes-Gato/microbiologia , Doenças dos Peixes/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/veterinária , Cebolas , Extratos Vegetais/farmacologia , Adjuvantes Imunológicos/isolamento & purificação , Aeromonas hydrophila/crescimento & desenvolvimento , Aeromonas hydrophila/imunologia , Animais , Antibacterianos/isolamento & purificação , Peixes-Gato/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Interações Hospedeiro-Patógeno , Imunidade Inata/efeitos dos fármacos , Cebolas/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Receptor 1 Toll-Like/genética , Receptor 1 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
J Fish Dis ; 44(5): 513-520, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33682163

RESUMO

Type III secretion system (T3SS)-dependent translocation has been used to deliver heterologous antigens by vaccine carriers into host cells. In this research, we identified the translocation signal of Edwardsiella piscicida T3SS effector EseG and constructed an antibiotic resistance-free balanced-lethal system as attenuated vaccine carrier to present antigens by T3SS. Edwardsiella piscicida LSE40 asd gene deletion mutant was constructed and complemented with pYA3342 harbouring the asd (aspartate ß-semialdehyde dehydrogenase) gene from Salmonella. Fusion proteins composed of EseG N-terminal 1-108 amino acids and the TEM1-ß-lactamase reporter were inserted in plasmid pYA3342. The fusion protein could secrete into the cell culture, translocate into HeLa cells, and localize in the membrane fraction. Then, the double gene deletion mutant LSE40ΔasdΔpurA was constructed as an attenuated vaccine carrier, and Aeromonas hydrophila GapA (glyceraldehyde-3-phosphate dehydrogenase) was fused with the translocation signal, instead of the TEM1-ß-lactamase reporter. The bivalent vaccine could protect blue gourami (Trichogaster trichopterus) against E. piscicida and A. hydrophila, with the relative per cent survival of 80.77% and 63.83%, respectively. These results indicated that EseG N-terminal 1-108 amino acid peptide was the translocation signal of E. piscicida T3SS, which could be used to construct bivalent vaccines based on an attenuated E. piscicida carrier.


Assuntos
Aeromonas hydrophila/imunologia , Vacinas Bacterianas/farmacologia , Edwardsiella/imunologia , Doenças dos Peixes/prevenção & controle , Sistemas de Secreção Tipo III/farmacologia , Vacinas Combinadas/farmacologia , Animais , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/prevenção & controle , Infecções por Enterobacteriaceae/veterinária , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Vacinas Atenuadas/farmacologia
10.
Mol Immunol ; 133: 14-22, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33610122

RESUMO

The polymeric immunoglobulin receptor (pIgR) is an important molecule in the mucosal immunity of teleosts. Previous studies have shown that pIgR can bind and transport polymeric immunoglobulins (pIgs), but few studies have focused on the binding of teleost pIgR to bacteria. In this study, we identified a gene encoding pIgR in largemouth bass (Micropterus salmoides). The pIgR gene contained two Ig-like domains (ILDs), which were homologous to ILD1 and ILD5 of mammalian pIgR. Our results showed that largemouth bass pIgR-ILD could combine with IgM. Moreover, we also found that largemouth bass pIgR-ILD could bind to Aeromonas hydrophila and Micrococcus luteus. Further analysis showed that largemouth bass pIgR-ILD could also combine with lipopolysaccharide (LPS), peptidoglycan (PGN) and various saccharides, and reduced binding to bacteria was observed with LPS and PGN treatment, indicating that largemouth bass pIgR could bind to bacteria to prevent infection and that saccharide binding is an important interaction mechanism between pIgR and bacteria. These results collectively demonstrated that largemouth bass pIgR not only combines with IgM but also binds to bacteria by various saccharides.


Assuntos
Aeromonas hydrophila/imunologia , Bass/imunologia , Imunoglobulina M/imunologia , Micrococcus luteus/imunologia , Receptores de Imunoglobulina Polimérica/genética , Receptores de Imunoglobulina Polimérica/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Bass/genética , Doenças dos Peixes/imunologia , Imunidade nas Mucosas/genética , Imunidade nas Mucosas/imunologia , Lipopolissacarídeos/imunologia , Peptidoglicano/imunologia , Filogenia , Domínios Proteicos/genética , Alinhamento de Sequência , Análise de Sequência de DNA
11.
J Immunol ; 206(6): 1337-1347, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33568398

RESUMO

Type I IFNs (IFN-Is) play pivotal roles in host defense against viral infections but remain enigmatic against bacterial pathogens. In this study, we recombinantly expressed and purified intact grass carp (Ctenopharyngodon idella) IFNφ1 (gcIFNφ1), a teleost IFN-I. gcIFNφ1 widely powerfully directly kills both Gram-negative and Gram-positive bacteria in a dose-dependent manner. gcIFNφ1 binds to LPS or peptidoglycan and provokes bacterial membrane depolarization and disruption, resulting in bacterial death. Furthermore, gcIFNφ1 can efficiently protect zebrafish against Aeromonas hydrophila infection and significantly reduce the bacterial loads in tissues by an infection model. In addition, we wonder whether antibacterial IFN-I members exist in other vertebrates. The amino acid compositions of representative IFN-Is with strong positive charges from Pisces, Amphibia, reptiles, Aves, and Mammalia demonstrate high similarities with those of 2237 reported cationic antimicrobial peptides in antimicrobial peptide database. Recombinant intact representative IFN-I members from the nonmammalian sect exhibit potent broad-spectrum robust bactericidal activity through bacterial membrane depolarization; in contrast, the bactericidal activity is very weak from mammalian IFN-Is. The findings display a broad-spectrum potent direct antimicrobial function for IFN-Is, to our knowledge previously unknown. The results highlight that IFN-Is are important and robust in host defense against bacterial pathogens, and unify direct antibacterial and indirect antiviral bifunction in nonmammalian jawed vertebrates.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Doenças dos Peixes/imunologia , Interferon Tipo I/metabolismo , Interferons/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Aeromonas hydrophila/imunologia , Aeromonas hydrophila/isolamento & purificação , Sequência de Aminoácidos , Animais , Carga Bacteriana , Carpas/genética , Carpas/imunologia , Carpas/metabolismo , Modelos Animais de Doenças , Doenças dos Peixes/microbiologia , Imunidade Inata , Interferon Tipo I/genética , Interferon Tipo I/isolamento & purificação , Interferons/genética , Interferons/isolamento & purificação , Testes de Sensibilidade Microbiana , Modelos Animais , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/imunologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/isolamento & purificação
12.
Mol Immunol ; 132: 21-29, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33524771

RESUMO

C-type lectins (CTLs) are calcium-dependent carbohydrate-binding proteins that mainly bind to carbohydrate-based or other ligands to mediate cell adhesion, recognize pathogens, and play important roles in the immune system. In the present study, a novel C-type lectin (OmCTL) isolated from Onychostoma macrolepis was investigated. The open reading frame of OmCTL comprises 468 bp, encoding a 155 amino acid polypeptide with an 18 amino acid putative signaling peptide. The predicted primary OmCTL structure contains a signal peptide, a single carbohydrate recognition domain (CRD) and an EPN/WND motif required for carbohydrate-binding specificity. Using tissue expression pattern analysis, OmCTL has been shownto be highly expressed in the liver, and is also detected in other tissues. OmCTL was significantly upregulated in the liver and spleen following infection with Aeromonas hydrophila, suggesting its involvement in immune response. The recombinant OmCTL protein (rOmCTL) agglutinated two gram-negative bacteria, Escherichia coli and A. hydrophila, in vitro in the presence of Ca2+, showing that it is a typical Ca2+-dependent carbohydrate-binding protein.Furthermore, rOmCTL purified from E. coli BL21 (DE3) strongly bound to LPS and PGN, as well as all tested bacteria in a Ca2+-independent manner. These results indicate that OmCTL plays a central role in the innate immune response and as a pattern recognition receptor that recognizes diverse pathogens among O. macrolepis.


Assuntos
Cyprinidae/imunologia , Imunidade Inata , Lectinas Tipo C/imunologia , Lipopolissacarídeos/imunologia , Peptidoglicano/imunologia , Aeromonas hydrophila/imunologia , Aglutinação/imunologia , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Clonagem Molecular , Cyprinidae/microbiologia , Escherichia coli/imunologia , Expressão Gênica , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Fígado/metabolismo , Filogenia , Ligação Proteica , Proteínas Recombinantes , Alinhamento de Sequência , Baço/metabolismo
13.
Int J Biol Macromol ; 172: 309-320, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33454323

RESUMO

Ribonuclease 1 (RNase1) is a vertebrate-specific enzyme that mainly performs digestive activity in herbivorous mammals. Here we used bacterial viability assays to explore its antimicrobial activity in blunt snout bream (Megalobrama amblycephala). The results showed that Ma-RNase1 rapidly killed Gram-negative and Gram-positive bacteria at micromolar concentrations. Ma-RNase1 increased the permeability of bacterial outer and inner membranes, thus reducing the integrity of bacterial cell wall and membrane. Moreover, Ma-RNase1 effectively counteracted the tissue damage and apoptosis caused by Aeromonas hydrophila infection. Quantitative real-time PCR and immunoblot analysis indicated that RNase1 mRNA and protein were up-regulated in the kidney and gut during infection. Furthermore, A. hydrophila infection significantly induced Tnf-α and Il-1ß mRNA expression in liver, but not in the RNase1 pre-treatment group. In addition, a significant increase in the expression of immune-related genes (Nf-κb and Tlr4) was found in liver, kidney and gut of A. hydrophila-infected fish, while a decrease in Myd88 and Tlr4 levels was found in liver, spleen, kidney and gut in the group pre-treated with RNase1. Collectively, these data suggest that Ma-RNase1 has antimicrobial function both in vitro and in vivo, and contributes to the protective effect and immune defense of blunt snout bream.


Assuntos
Aeromonas hydrophila/imunologia , Cyprinidae/genética , Doenças dos Peixes/genética , Proteínas de Peixes/genética , Infecções por Bactérias Gram-Negativas/genética , Ribonucleases/genética , Aeromonas hydrophila/crescimento & desenvolvimento , Aeromonas hydrophila/patogenicidade , Animais , Membrana Celular/imunologia , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Cyprinidae/imunologia , Cyprinidae/microbiologia , Resistência à Doença/genética , Resistência à Doença/imunologia , Doenças dos Peixes/enzimologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/patologia , Proteínas de Peixes/imunologia , Regulação da Expressão Gênica , Infecções por Bactérias Gram-Negativas/enzimologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/patologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Rim/imunologia , Rim/microbiologia , Fígado/imunologia , Fígado/microbiologia , Viabilidade Microbiana , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Ribonucleases/imunologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
14.
BMC Vet Res ; 16(1): 450, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213475

RESUMO

BACKGROUND: Interferon (IFN) regulatory factors (IRFs), as transcriptional regulatory factors, play important roles in regulating the expression of type I IFN and IFN- stimulated genes (ISGs) in innate immune responses. In addition, they participate in cell growth and development and regulate oncogenesis. RESULTS: In the present study, the cDNA sequence of IRF10 in common carp (Cyprinus carpio L.) was characterized (abbreviation, CcIRF10). The predicted protein sequence of CcIRF10 shared 52.7-89.2% identity with other teleost IRF10s and contained a DNA-binding domain (DBD), a nuclear localization signal (NLS) and an IRF-associated domain (IAD). Phylogenetic analysis showed that CcIRF10 had the closest relationship with IRF10 of Ctenopharyngodon idella. CcIRF10 transcripts were detectable in all examined tissues, with the highest expression in the gonad and the lowest expression in the head kidney. CcIRF10 expression was upregulated in the spleen, head kidney, foregut and hindgut upon polyinosinic:polycytidylic acid (poly I:C) and Aeromonas hydrophila stimulation and induced by poly I:C, lipopolysaccharide (LPS) and peptidoglycan (PGN) in peripheral blood leucocytes (PBLs) and head kidney leukocytes (HKLs) of C. carpio. In addition, overexpression of CcIRF10 was able to decrease the expression of the IFN and IFN-stimulated genes PKR and ISG15. CONCLUSIONS: These results indicate that CcIRF10 participates in antiviral and antibacterial immunity and negatively regulates the IFN response, which provides new insights into the IFN system of C. carpio.


Assuntos
Carpas/genética , Carpas/imunologia , Fatores Reguladores de Interferon/genética , Aeromonas hydrophila/imunologia , Animais , Carpas/metabolismo , DNA Complementar , Proteínas de Peixes , Lipopolissacarídeos/imunologia , Peptidoglicano/imunologia , Filogenia , Poli I-C/imunologia , Análise de Sequência de DNA , Distribuição Tecidual
15.
J Immunol ; 205(12): 3443-3455, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33199536

RESUMO

The innate immune system is an ancient defense system in the process of biological evolution, which can quickly and efficiently resist pathogen infection. In mammals, mannose-binding lectin (MBL) is a key molecule in the innate immune and plays an essential role in the first line of host defense against pathogenic bacteria. However, the evolutionary origins and ancient roles of immune defense of MBL and its mechanism in clearance of microbial pathogens are still unclear, especially in early vertebrates. In this study, Oreochromis niloticus MBL (OnMBL) was successfully isolated and purified from the serum of Nile tilapia (O. niloticus). The OnMBL was able to bind and agglutinate with two important pathogens of tilapia, Streptococcus agalactiae and Aeromonas hydrophila Interestingly, the OnMBL was able to significantly inhibit the proliferation of pathogenic bacteria and reduce the inflammatory response. Upon bacterial challenge, the downregulation of OnMBL expression by RNA interference could lead to rapid proliferation of the pathogenic bacteria, ultimately resulting in tilapia death. However, the phenotype was rescued by reinjection of the OnMBL, which restored the healthy status of the knockdown tilapia. Moreover, a mechanistic analysis revealed that the OnMBL could clear pathogenic bacteria by collaborating with cell-surface calreticulin to facilitate phagocytosis in a complement activation-independent manner. To our knowledge, these results provide the first evidence on the antibacterial response mechanism of MBL performing evolutionary conserved function to promote opsonophagocytosis of macrophages in early vertebrates and reveals new insights into the understanding of the evolutionary origins and ancient roles basis of the C-type lectins in the innate immune defense.


Assuntos
Aeromonas hydrophila/imunologia , Ciclídeos/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Lectina de Ligação a Manose/imunologia , Infecções Estreptocócicas/imunologia , Streptococcus agalactiae/imunologia , Animais , Ciclídeos/microbiologia , Feminino , Doenças dos Peixes/microbiologia , Proteínas de Peixes/química , Proteínas de Peixes/isolamento & purificação , Infecções por Bactérias Gram-Negativas/veterinária , Lectina de Ligação a Manose/química , Lectina de Ligação a Manose/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estreptocócicas/veterinária
16.
Mol Immunol ; 126: 73-86, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32771671

RESUMO

Natural killer enhancing factor (NKEF) of peroxiredoxin family is an important innate immune molecule with having anti-oxidant activity. Although this gene has already been studied in a few fish species, it is yet to be identified and functionally characterised in Indian major carps. In the present study, the complete NKEF-B cDNA of rohu, Labeo rohita was cloned that encoded a putative protein of 197 amino acids. The phylogenetic study showed that L. rohita NKEF-B (LrNKEF-B) is closely related to NKEF-B of Cyprinus carpio and Danio rerio species. Tissue-specific expression of LrNKEF-B gene revealed the highest transcript level in the liver tissue. In the ontogeny study, the highest level of the expression was observed in milt and at 18 h post-development. The expression pattern of this gene was also studied in various pathogen models viz., Gram-negative bacteria (Aeromonas hydrophila), ectoparasite (Argulus siamensis) and a dsRNA viral analogue (poly I:C) in the liver and anterior kidney tissues of L. rohita juveniles. During A. hydrophila infection, the increase in expression of transcripts was observed at 3 h post-infection in both liver (15-fold) and anterior kidney (8-fold). In A. siamensis infection, the expression gradually increased up to 3 d post-infection in the anterior kidney, whereas in liver 3-fold up-regulation was noticed at 12 h post-infection. Similarly, during poly I:C stimulation, up-regulation of NKEF-B transcript was observed in anterior kidney from 1 h to 24 h post-stimulation and down-regulated afterwards whereas, the transcript level increased gradually from 6 h to 15 d post-stimulation in liver tissue. In vitro exposure to concanavalin, A and formalin-killed A. hydrophila upregulated NKEF-B gene expression in anterior kidney and peripheral blood leukocytes of L. rohita, however, down-regulated the same in the splenic leukocytes. A recombinant protein of LrNKEF-B (rLrNKEF-B) of 22 kDa was produced and it showed anti-oxidant activity by protecting supercoiled DNA and reducing insulin disulfide bonds. The minimum bactericidal concentration of this recombinant protein was found to be 4.54 µM against A. hydrophila and Staphylococcus aureus. Interestingly, rLrNKEF-B showed relative percent survival of 72.6 % in A. hydrophila challenged L. rohita, and the survival was found to be associated with a high level of expression of different cytokines, anti-oxidant genes and perforin in the rLrNKEF-B treated L. rohita. An indirect ELISA assay for estimation of NKEF was developed in L. rohita, and the concentrations of NKEF-B increased with time periods post A. hydrophila challenge viz., 0 h (42.56 ng/mL), 12 h (174 ng/mL) and 48 h (370 ng/mL) in rohu serum. Our results suggest a crucial role of LrNKEF-B in innate immunity against biotic stress and oxidative damage and also having antibacterial activity.


Assuntos
Carpas/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Imunidade Inata , Peroxirredoxinas/imunologia , Aeromonas hydrophila/imunologia , Animais , Arguloida/imunologia , Carpas/genética , Carpas/microbiologia , Carpas/parasitologia , Clonagem Molecular , Doenças dos Peixes/sangue , Doenças dos Peixes/microbiologia , Doenças dos Peixes/parasitologia , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica , Rim Cefálico/enzimologia , Rim Cefálico/imunologia , Fígado/enzimologia , Fígado/imunologia , Estresse Oxidativo/imunologia , Peroxirredoxinas/genética , Filogenia , Poli I-C/imunologia , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Staphylococcus aureus/imunologia
17.
J Exp Zool A Ecol Integr Physiol ; 333(10): 756-766, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32798287

RESUMO

As a free-living larval stage of a vertebrate, tadpoles are good subjects for the study of the development of physiological systems and the study of evolutionarily conserved, context-dependent responses to variable environments. While the basic components of innate and adaptive immune defenses in tadpoles are known, the impact of glucocorticoids on immune defenses in tadpoles is not well-studied. We completed four experiments to assess effects of elevation of corticosterone on humoral innate defenses and antibody-mediated immunity in southern leopard frog tadpoles (Lithobates sphenocephalus). To test humoral innate defense within the tadpoles exposed to short-term and long-term elevation of glucocorticoids, we exposed tadpoles to exogenous corticosterone for different lengths of time in each experiment (0-84 days). We used bacterial killing assays to assess humoral innate immune defense. To test antibody-mediated immune responses, we again exposed tadpoles to exogenous corticosterone, while also exposing them to Aeromonas hydrophila. We used A. hydrophila ELISA comparing IgM and IgY responses among groups. Plasma from corticosterone-dosed tadpoles killed more A. hydrophila than control tadpoles each following a short-term (14 day) and long-term (56 day) exposure to exogenous corticosterone. Conversely, corticosterone-dosed tadpoles had significantly lower IgM and IgY against A. hydrophila after 12 weeks. Our fourth experiment revealed that the lower IgY response is a product of weaker, delayed isotype switching compared with controls. These results show that elevated corticosterone has differential effects on innate and acquired immunity in larval southern leopard frogs, consistent with patterns in more derived vertebrates and in adult frogs.


Assuntos
Corticosterona/farmacologia , Imunidade Humoral/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Rana pipiens/imunologia , Aeromonas hydrophila/imunologia , Animais , Atividade Bactericida do Sangue/efeitos dos fármacos , Relação Dose-Resposta a Droga , Larva , Rana pipiens/sangue , Rana pipiens/fisiologia
18.
Int J Biol Macromol ; 162: 11-23, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32531365

RESUMO

The expression and localization of different isoforms of creatine kinase in Pelodiscus sinensis (PSCK) were studied to reveal the role of PSCK isozymes (PSCK-B, PSCK-M, PSCK-S) under bacterial infection-induced immunologic stress. The computational molecular dynamics simulations predicted that PSCK-S would mostly possess a kinase function in a structural aspect when compared to PSCK-B and PSCK-M. The assay of biochemical parameters such as total superoxide dismutase (T-SOD), lactate dehydrogenase (LDH), malondialdehyde (MDA), catalase (CAT), and the content of ATP were measured along with total PSCK activity in different tissue samples under bacterial infection. The expression detections of PSCK isozymes in vitro and in vivo were overall well-matched where PSCK isozymes were expressed differently in P. sinensis tissues. The results showed that PSCK-B mostly contributes to the spleen, followed by the liver and myocardium; PSCK-M mostly contributes to the liver, followed by the myocardium and skeletal muscle, while PSCK-S contributes to the spleen and is uniquely expressed in skeletal muscle. Our study suggests that the various alterations of PSCK isozymes in tissues of P. sinensis are prone to defense the bacterial infection and blocking energetic imbalance before severe pathogenesis turned on in P. sinensis.


Assuntos
Infecções Bacterianas/enzimologia , Creatina Quinase/química , Isoformas de Proteínas/química , Estresse Fisiológico/imunologia , Tartarugas/metabolismo , Trifosfato de Adenosina/metabolismo , Aeromonas hydrophila/imunologia , Animais , Infecções Bacterianas/genética , Infecções Bacterianas/imunologia , Infecções Bacterianas/metabolismo , Catalase/metabolismo , Creatina Quinase/genética , Creatina Quinase/metabolismo , Regulação da Expressão Gênica/imunologia , Imuno-Histoquímica , L-Lactato Desidrogenase/metabolismo , Fígado/química , Fígado/enzimologia , Malondialdeído/metabolismo , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Miocárdio/química , Miocárdio/enzimologia , Filogenia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Análise de Sequência de Proteína , Baço/química , Baço/enzimologia , Superóxido Dismutase/metabolismo , Tartarugas/genética , Tartarugas/imunologia , Tartarugas/microbiologia
19.
Front Immunol ; 11: 904, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32457762

RESUMO

The effects of the oral administration of Rehmannia glutinosa polysaccharide (RGP-1) on the immunoregulatory properties, antioxidant activity, and resistance against Aeromonas hydrophila in Cyprinus carpio L. were investigated. The purified RGP-1 (250, 500, and 1,000 µg/mL) was co-cultured with the head kidney cells of the common carp. The proliferation and phagocytosis activities of the head kidney cells, and the concentration of nitric oxide (NO) and cytokines in the culture medium were determined. Next, 300 common carps (47.66 ± 0.43 g) were randomly divided into five groups; the two control groups (negative and positive) were administered sterile PBS and the three treatment groups were administered different concentrations of RGP-1 (250, 500, and 1,000 µg/mL) for seven days. Subsequently, the positive and treatment groups were infected with A. hydrophila, and the negative group was administered sterile PBS for 24 h. The concentration of NO, cytokines, lysozyme (LZM), and alkaline phosphatase (AKP) in serum, the total antioxidant capacity (T-AOC), the levels of malonaldehyde (MDA) and glutathione (GSH), and the total activities of superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the hepatopancreas of the common carp were tested. We observed that RGP-1 could significantly enhance the proliferation and phagocytosis activities (P < 0.05), besides inducing the production of NO, pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, IL-12) and anti-inflammatory cytokines (IL-10, TGF-ß) (P < 0.05) in vitro. The in vivo experimental results revealed that RGP-1 significantly enhanced NO production, protein levels of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, IL-12), LZM and AKP activities, and the antioxidant content (T-AOC, SOD, CAT, GSH, GSH-Px, and MDA) compared to that observed in the negative group prior to A. hydrophila infection (P < 0.05). NO, pro-inflammatory cytokines, LZM and AKP activities were significantly lower than that in the positive group after infection (P < 0.05). However, whether infected or not, the expression of anti-inflammatory cytokines (IL-10, TGF-ß) increased significantly in the RGP-1-treated groups (P < 0.05). Therefore, the results suggested that RGP-1 could enhance the non-specific immunity, antioxidant activity and anti-A. hydrophila activity of the common carp, and could be used as a safe and effective feed additive in aquaculture.


Assuntos
Aeromonas hydrophila/efeitos dos fármacos , Antibacterianos/administração & dosagem , Antioxidantes/administração & dosagem , Carpas , Infecções por Bactérias Gram-Negativas/prevenção & controle , Rim Cefálico/efeitos dos fármacos , Fatores Imunológicos/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/administração & dosagem , Rehmannia , Administração Oral , Aeromonas hydrophila/imunologia , Aeromonas hydrophila/patogenicidade , Animais , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Carpas/imunologia , Carpas/metabolismo , Carpas/microbiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Rim Cefálico/imunologia , Rim Cefálico/metabolismo , Fatores Imunológicos/isolamento & purificação , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Polissacarídeos/isolamento & purificação , Rehmannia/química
20.
Infect Genet Evol ; 82: 104320, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32298854

RESUMO

OBJECTIVES: Gram-negative bacteria are among the causative microorganisms for zoonotic diseases in humans and teleosts. Outer membrane proteins (Omps) of Aeromonas hydrophila, a gram-negative bacterium, are critical for the subcellular integration to eukaryotic cell that can modulate the functions of macrophages. Hence Omps are recognized as immune markers for the vaccine development. METHODS: In the present study, a 3-D model of Omps was identified using in silico technique and recognized through the Swiss model web-server and confirmed with Procheck and ProSA server.. The B-cell binding sites of the protein were selected from sequence alignment.. Further, the identification of B-cell epitope was carried out using modules of BCpred server (i.e., BCPred and Amino Acid Pairs). The identified antigenic amino acid sequences for B-cells were used to determine the T-cell epitope (both MHC I & II allelic binding sequences) using ProPred 1 and ProPred servers. RESULTS: The epitopic regions (9 mer: LAGKTTNES and GFDGSQYGK) in the Omps that are bound together with the MHC molecules (MHC-I & II), and have maximum possible numbers of MHC alleles are recognized. It was observed that Omps of A. hydrophila are conserved across the serotypes and are immunogenic. These epitopes can stimulate significant immune responses and can be advantageous while preparing peptide-based vaccines against A. hydrophila infections. Thus, suggesting the use of Omps in the development of vaccines and immunotherapeutics against the bacterial diseases in humans and teleosts.


Assuntos
Aeromonas hydrophila/imunologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/imunologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Aeromonas hydrophila/química , Animais , Desenho de Fármacos , Epitopos de Linfócito B/química , Epitopos de Linfócito T/química , Proteínas de Peixes/química , Proteínas de Peixes/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Reprodutibilidade dos Testes
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