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1.
Artigo em Inglês | MEDLINE | ID: mdl-31838832

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) infects the lower respiratory airway of humans, leading to severe acute respiratory failure. Unlike human dipeptidyl peptidase 4 (hDPP4), a receptor for MERS-CoV, mouse DPP4 (mDPP4) failed to support MERS-CoV infection. Consequently, diverse transgenic mouse models expressing hDPP4 have been developed using diverse methods, although some models show no mortality and/or only transient and mild-to-moderate clinical signs following MERS-CoV infection. Additionally, overexpressed hDPP4 is associated with neurological complications and breeding difficulties in some transgenic mice, resulting in impeding further studies. Here, we generated stable hDPP4-transgenic mice that were sufficiently susceptible to MERS-CoV infection. The transgenic mice showed weight loss, decreased pulmonary function, and increased mortality with minimal perturbation of overexpressed hDPP4 after MERS-CoV infection. In addition, we observed histopathological signs indicative of progressive pulmonary fibrosis, including thickened alveolar septa, infiltration of inflammatory monocytes, and macrophage polarization as well as elevated expression of profibrotic molecules and acute inflammatory response in the lung of MERS-CoV-infected hDPP4-transgenic mice. Collectively, we suggest that this hDPP4-transgenic mouse is useful to enable understanding of the pathogenesis of MERS-CoV infection and for antiviral research and vaccine development against the virus.

2.
Pharm Biol ; 57(1): 369-379, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31156004

RESUMO

Context: Silk peptide from cocoons of silkworm (Bombyx mori L., Bombycidae) has been employed as a biomedical material and exhibits various bioactivities, including immune-modulating activity. Objective: We analyzed whether silk peptide exerts direct modulating effects on NK cells using an NK cell line in vitro and ex vivo splenocytes. We also attempted to delineate the mechanism underlying the modulation. Material and methods: In vitro activity of silk peptide on NK cells was determined by measurement of cytolytic activity against K562 cells at an effector-to-target ratio of 5:1 after incubation of NK-92MI cells with silk peptide (0-2000 µg/mL) for 48 and 72 h. Ex vivo activity of silk peptide on mouse splenic NK cells was determined similarly by using YAC-1 cells. Results: Treatment of NK-92MI NK cells with silk peptide (500-2000 µg/mL) significantly increased cytolytic activity on target cells by 2- to 4-fold. The same concentrations (500-2000 µg/mL) of silk peptide treatment also significantly enhanced the cytolytic activity of splenic NK cells against YAC-1 cells. Silk peptide treatment of IL-2-stimulated splenocytes induced enhanced expression of Th1, 2 and 17 cytokines including TNF-α, IFN-γ, IL-6, IL-4 and IL-17. Finally, ex vivo treatment with silk peptide on mouse splenocytes significantly enhanced the degree of NK cell maturation in a dose-dependent manner from 3.49 to 23.79%. Discussion and conclusions: These findings suggest that silk peptide stimulates NK cells, thereby influencing systemic immune functions and improving natural immunity. Thus, silk peptide could be useful as a complementary therapy in cancer patients.


Assuntos
Bombyx , Fatores Imunológicos/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Seda/química , Baço/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Citocinas/imunologia , Relação Dose-Resposta a Droga , Humanos , Fatores Imunológicos/isolamento & purificação , Células K562 , Células Matadoras Naturais/imunologia , Fragmentos de Peptídeos/isolamento & purificação , Seda/imunologia , Baço/citologia , Baço/imunologia
3.
Immunobiology ; 224(4): 502-510, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31126693

RESUMO

Beta-defensins contribute to host innate defense against various pathogens, including viruses, although the details of their roles in innate immune cells are unclear. We previously reported that human ß-defensin 2 (HBD 2) activates primary innate immunity against viral infection and suggested that it plays a role in the induction of the adaptive immune response. We analyzed the mechanisms by which HBD 2 primes innate antiviral immunity and polarized activation of macrophage-like THP-1 cells using the receptor-binding domain (RBD) of Middle East respiratory syndrome coronavirus (MERS-CoV) spike protein (S RBD) as a model antigen. The expression of nucleotide-binding oligomerization domain containing 2 (Nod2), type I interferons, (IFNs), and proinflammatory mediators was enhanced in S RBD-HBD 2-treated THP-1 cells. S RBD-HBD 2 treatment also enhanced phosphorylation and activation of receptor-interacting serine/threonine-protein kinase 2 and IFN regulatory factor 3 compared to S RBD alone. Finally, HBD 2-conjugated S RBD interacted with C-C chemokine receptor 2 (CCR2), and Nod2 was involved in HBD 2-mediated CCR2 signaling, which was associated with the activation and M1 polarization of THP-1 cells. Therefore, HBD 2 promotes CCR2-mediated Nod2 signaling, which induces production of type I IFNs and an inflammatory response, and enhances primary innate immunity leading to an effective adaptive immune response to HBD 2-conjugated antigen.


Assuntos
Imunidade Inata , Macrófagos/imunologia , Macrófagos/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Receptores CCR2/metabolismo , Transdução de Sinais , beta-Defensinas/metabolismo , Animais , Citocinas/metabolismo , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Ativação de Macrófagos/imunologia , Células THP-1 , Células Vero
4.
Protein Pept Lett ; 26(9): 676-683, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30950341

RESUMO

BACKGROUND: The number of oral vaccines is still limited due to many difficulties suffered in the intestinal environment, such as mucosal clearance, vast area, harsh conditions, deteriorative enzymes, impermeability, tolerance, etc. Numerous strategies have focused on directing antigen to the receptors of M cells, which is the main gateway to acquire and initiate specific responses to antigens in intestine. FimHrb is a receptor binding domain of type 1 of fimbriae from E. coli and Salmonella that can bind to GP2 receptor expressed exclusively on M cells. OBJECTIVE: In this study, we evaluated the potential of FimHrb for oral vaccine development via its ability to adhere M cells. METHODS: The coding gene of FimHrb fused Green Fluorescent Protein (GFP) was cloned and expressed intracellularly in E. coli host strain. The recombinant protein FimHrb-GFP was then purified by IMAC method through 6x His tag designed downstream of GFP. Finally, the purified protein was monitored its binding on murine M cells in Payer Patch region. RESULTS: Following the methods mentioned above, the coding gene FimHrb-GFP was successfully cloned into vector pET22b and intracellularly expressed in soluble form at low temperature induction. The purity and the recovered yield of this protein were 90% and 20%, respectively. After that, the adhesion of FimHrb-GFP was monitored in murine small intestine, which showed that the protein bound to Peyer Patch region and did not restrict on M cells. CONCLUSION: With the present data, we revealed a candidate protein FimHrb targeted receptor on M cells for oral vaccine development and other factors in E. coli would supplement FimH to provide the specific invasion of these bacteria via M cells.


Assuntos
Adesinas de Escherichia coli/química , Proteínas de Fímbrias/química , Proteínas de Fluorescência Verde/química , Proteínas Recombinantes de Fusão/química , Adesinas de Escherichia coli/genética , Animais , Linhagem Celular , Escherichia coli/genética , Proteínas de Fímbrias/genética , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Imunidade nas Mucosas , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Camundongos , Ligação Proteica , Domínios Proteicos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
5.
Food Sci Biotechnol ; 27(6): 1823-1831, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30483447

RESUMO

This study examined the efficacy of Atractylodes macrocephala Koidz (AMK) protein and polysaccharide extracts as adjuvant or adjuvant booster when given together with porcine pleuropneumonia vaccine. Experimental mice (n = 5/group) were subcutaneously immunized with 25 µg ApxIIA #3 antigen, a target protein against A. pleuropneumoniae, together with alum and/or various concentrations (0-500 µg) of the AMK extracts, while the control group received PBS only. Immunization with ApxIIA #3 antigen increased the antigen-specific IgG titer and this increase was enhanced in the immunization together with AMK protein, but not polysaccharide extract. Supplementation of AMK protein extract exhibited dose-dependent increases in the antigen-induced protective immunity against A. pleuropneumoniae challenge and in the lymphocyte proliferation specific to the antigen. Glycoproteins present in the AMK extract were the active components responsible for immune response induction. Collectively, the present findings suggest that AMK glycoproteins are useful as immune stimulating adjuvant or adjuvant booster.

6.
Immune Netw ; 18(5): e37, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30402332

RESUMO

Silk peptide, the hydrolysate of silk protein derived from cocoons, has been employed as a biomedical material and is believed to be safe for human use. Silk peptide display various bioactivities, including anti-inflammatory, immune-regulatory, anti-tumor, anti-viral, and anti-bacterial. Although earlier investigations demonstrated that silk peptide stimulates macrophages and the production of pro-inflammatory cytokines, its effect on natural killer (NK) cell function has not yet been explored. In this study, we initially confirmed that silk peptide enhances NK cell activity in vitro and ex vivo. To assess the modulatory activity of silk peptide on NK cells, mice were fed various amounts of a silk peptide-supplemented diet for 2 months and the effects on immune stimulation, including NK cell activation, were evaluated. Oral administration of silk peptide significantly enhanced the proliferation of mitogen- or IL-2-stimulated splenocytes. In addition, oral silk peptide treatment enhanced the frequency and degree of maturation of NK cells in splenocytes. The same treatment also significantly enhanced the target cell cytolytic activity of NK cells, which was determined by cell surface CD107a expression and intracellular interferon-γ expression. Finally, oral administration of silk peptide stimulated T helper 1-type cytokine expression from splenic lymphocytes. Collectively, our results suggest that silk peptide potentiates NK cell activity in vivo and could be used as a compound for immune-modulating anti-tumor treatment.

7.
Microb Cell Fact ; 17(1): 146, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30217208

RESUMO

BACKGROUND: Dengue is a rapidly spreading mosquito borne tropical viral disease affecting hundreds of millions of people across the globe annually. The dengue virus (DENV) includes four genetically distinct serotypes that cause serious life-threatening infections, including dengue hemorrhagic fever/dengue shock syndrome. Dengue vaccine development is complicated by the possibility of vaccine-enhanced severe dengue disease due to antibody-dependent enhancement by pre-existing cross-reactivity, as well as homotypic antibodies. Thus, the development of an efficacious dengue vaccine conferring simultaneous and durable immunity to each of the four DENV serotypes has not yet been developed despite years of research. For mass immunization in deeply affected resource-limited countries, oral vaccination is considered more beneficial than conventional approaches. Therefore, in a continuing effort towards designing economical and potent vaccine candidates, the current study applied yeast surface display technology to develop an oral dengue vaccine candidate using whole recombinant yeast cells displaying the recombinant fusion protein of M cell targeting ligand Co1 fused to the synthetic consensus dengue envelope domain III (scEDIII). Female Balb/c mice were orally fed with recombinant yeast cells and immunogenicity in terms of systemic and mucosal immune responses was monitored. RESULTS: Immunofluorescence microscopy with dengue specific antibody and fluorescein isothiocyanate-conjugated anti-mouse IgG antibody clearly showed that recombinant protein Co1-scEDIII-AGA was localized on the cell surface of the respective clones in comparison with scEDIII-Co1 and Mock cells with no fluorescence. Oral dosage applications of surface displayed Co1-scEDIII-AGA stimulated a systemic humoral immune response in the form of dengue-specific serum IgG, as well as a mucosal immune response in the form of secretory immunoglobulin A (sIgA). Antigen-specific B cell responses in isolated lymphoid cells from the spleen and Peyer's patches further supported an elevated mucosal immune response. In addition, surface displayed Co1-scEDIII-AGA feeding elicited strong immune responses in comparison with scEDIII-Co1 and Mock following intraperitoneal booster with purified scEDIII antigen. CONCLUSIONS: Surface displayed preparations of Co1-scEDIII-AGA induced strong immunogenicity compared with non-displayed scEDIII-Co1. Prior studies have supported the neutralization potential of scEDIII constructs against all four serotypes. Thus, the oral administration of genetically engineered yeast whole cells displaying biologically active Co1-scEDIII fusion protein without any further processing shows prospective as a potent oral vaccine candidate against dengue viral infection.


Assuntos
Vacinas contra Dengue/administração & dosagem , Vírus da Dengue/imunologia , Saccharomyces cerevisiae/genética , Animais , Técnicas de Visualização da Superfície Celular , Ensaio de Imunoadsorção Enzimática , Feminino , Imunidade Humoral , Imunidade nas Mucosas , Camundongos Endogâmicos BALB C , Saccharomyces cerevisiae/metabolismo , Proteínas Virais/análise , Proteínas Virais/genética , Proteínas Virais/imunologia
8.
Virol J ; 15(1): 124, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089512

RESUMO

BACKGROUND: Antimicrobial peptides (AMPs) are primarily known for their innate immune defense against invading microorganisms, including viruses. In addition, recent research has suggested their modulatory activity in immune induction. Given that most subunit vaccines require an adjuvant to achieve effective immune induction through the activation of innate immunity, AMPs are plausible candidate molecules for stimulating not only innate immune but also adaptive immune responses. RESULTS: In this study, we investigated the ability of human ß-defensin (HBD) 2 to promote antiviral immunity in vitro and in vivo using a receptor-binding domain (RBD) of Middle East respiratory syndrome-coronavirus (MERS-CoV) spike protein (S RBD) as a model antigen (Ag). When HBD 2-conjugated S RBD was used to treat THP-1 human monocytic cells, the expression levels of antiviral (IFN-ß, IFN-γ, MxA, PKR, and RNaseL) and primary immune-inducing (NOD2, TNF-α, IL-1ß, and IL-6) molecules were enhanced compared to those expressed after treatment with S RBD only. The expression of chemokines capable of recruiting leukocytes, including monocytes/macrophages, natural killer cells, granulocytes, T cells, and dendritic cells, was also increased following HBD 2-conjugated S RBD treatment. More important, immunization of mice with HBD 2-conjugated S RBD enhanced the immunogenicity of the S RBD and elicited a higher S RBD-specific neutralizing antibody response than S RBD alone. CONCLUSIONS: We conclude that HBD 2 activates the primary antiviral innate immune response and may also mediate the induction of an effective adaptive immune response against a conjugated Ag.


Assuntos
Imunidade Inata/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , beta-Defensinas/imunologia , Imunidade Adaptativa/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos Virais/química , Antígenos Virais/imunologia , Antivirais/imunologia , Linhagem Celular Tumoral , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Humanos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Coronavírus da Síndrome Respiratória do Oriente Médio/química , Glicoproteína da Espícula de Coronavírus/química , Células THP-1 , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/imunologia , Células Vero , Vacinas Virais/administração & dosagem , beta-Defensinas/química
9.
Immune Netw ; 18(3): e21, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29984039

RESUMO

Porcine epidemic diarrhea virus (PEDV) is a contagious coronavirus infecting pigs that leads to significant economic losses in the swine industry. Given that PEDV infection occurs in gut epithelial cells mainly via the fecal-oral route, induction of PEDV-specific immune responses in the mucosal compartment is required for protective immunity against viral infection. However, an effective mucosal vaccine against the currently prevalent PEDV strain is not available. In this study, we demonstrated that the N-terminal domain (NTD) of the spike (S) protein of PEDV represents a new vaccine candidate molecule to be applied via the mucosal route. We first established an Escherichia coli expression system producing the partial NTD (NTD231-501) of the PEDV S protein. Orally administered NTD231-501 protein specifically interacted with the apical area of M cells in the follicle-associated epithelium of Peyer's patch. Additionally, the NTD protein induced antigen-specific immune responses in both the systemic and mucosal immune compartments when administered orally. Collectively, we propose the NTD of the PEDV S protein to be a candidate mucosal vaccine molecule.

10.
Cell Immunol ; 325: 41-47, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29397905

RESUMO

Mucosal vaccination is an ideal strategy to induce protective immunity in both mucosal and parenteral areas. Successful induction of an antigen-specific immune response via mucosal administration essentially requires the effective delivery of antigen into a mucosal immune inductive site, which depends on antigen delivery into M cells. We previously reported that M cells specifically express C5aR, and antigen targeting to C5aR by using specific ligands, including Co1 peptide, promotes the antigen-specific immune response in both mucosal and systemic immune compartments. In this study, we found that application of the Co1 peptide to dengue virus antigen containing CD8 T cell epitopes effectively induced an antigen-specific IFN-γ-producing CD8+ T cell response after oral mucosal administration of antigen. Consequently, we suggest that Co1 peptide-mediated C5aR targeting of antigen into M cells can be used for the induction of an effective antigen-specific CD8+ T cell immune response in oral mucosal vaccine development.


Assuntos
Vacinas contra Dengue/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Proteínas não Estruturais Virais/imunologia , Animais , Antígenos , Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Vírus da Dengue/metabolismo , Modelos Animais de Doenças , Imunidade nas Mucosas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Membrana Mucosa/imunologia , Vacinação , Proteínas não Estruturais Virais/metabolismo
11.
Microb Cell Fact ; 17(1): 24, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29452594

RESUMO

BACKGROUND: Dengue is listed as a neglected tropical disease by the Center for Disease Control and Preservation, as there are insufficient integrated surveillance strategies, no effective treatment, and limited licensed vaccines. Consisting of four genetically distinct serotypes, dengue virus (DENV) causes serious life-threatening infections due to its complexity. Antibody-dependent enhancement by pre-existing cross-reactive as well as homotypic antibodies further worsens the clinical symptoms of dengue. Thus, a vaccine conferring simultaneous and durable immunity to each of the four DENV serotypes is essential to restrict its escalation. In deeply affected resource-limited countries, oral vaccination using food-grade organisms is considered to be a beneficial approach in terms of costs, patient comfort, and simple logistics for mass immunization. The current study used a mouse model to explore the immunogenicity of an oral dengue vaccine candidate prepared using whole recombinant yeast cells (WC) and cell-free extracts (CFE) from cells expressing recombinant Escherichia coli heat-labile toxin protein B-subunit (LTB) fused to the consensus dengue envelope domain III (scEDIII). Mice were treated orally with recombinant WC and CFE vaccines in 2-week intervals for 4 weeks and changes in systemic and mucosal immune responses were monitored. RESULTS: Both WC and CFE dosage applications of LTB-scEDIII stimulated a systemic humoral immune response in the form of dengue-specific serum IgG as well as mucosal immune response in the form of secretory sIgA. Antigen-specific B cell responses in isolated lymphoid cells from the spleen and Peyer's patches further indicated an elevated mucosal immune response. Cellular immune response estimated through lymphocyte proliferation assay indicated higher levels in CFE than WC dosage. Furthermore, sera obtained after both oral administrations successfully neutralized DENV-1, whereas CFE formulation only neutralized DENV-2 serotype, two representative serotypes which cause severe dengue infection. Sera from mice that were fed CFE preparations demonstrated markedly higher neutralizing titers compared to those from WC-fed mice. However, WC feeding elicited strong immune responses, which were similar to the levels induced by CFE feeding after intraperitoneal booster with purified scEDIII antigen. CONCLUSIONS: CFE preparations of LTB-scEDIII produced strong immunogenicity with low processing requirements, signifying that this fusion protein shows promise as a potent oral vaccine candidate against dengue viral infection.


Assuntos
Vacinas contra Dengue/imunologia , Vírus da Dengue/patogenicidade , Dengue/prevenção & controle , Administração Oral , Animais , Dengue/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C
12.
Plant Biotechnol J ; 16(7): 1283-1294, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29223138

RESUMO

Dengue is a major global disease requiring improved treatment and prevention strategies. The recently licensed Sanofi Pasteur Dengvaxia vaccine does not protect children under the age of nine, and additional vaccine strategies are thus needed to halt this expanding global epidemic. Here, we employed a molecular engineering approach and plant expression to produce a humanized and highly immunogenic poly-immunoglobulin G scaffold (PIGS) fused to the consensus dengue envelope protein III domain (cEDIII). The immunogenicity of this IgG Fc receptor-targeted vaccine candidate was demonstrated in transgenic mice expressing human FcγRI/CD64, by induction of neutralizing antibodies and evidence of cell-mediated immunity. Furthermore, these molecules were able to prime immune cells from human adenoid/tonsillar tissue ex vivo as evidenced by antigen-specific CD4+ and CD8+ T-cell proliferation, IFN-γ and antibody production. The purified polymeric fraction of dengue PIGS (D-PIGS) induced stronger immune activation than the monomeric form, suggesting a more efficient interaction with the low-affinity Fcγ receptors on antigen-presenting cells. These results show that the plant-expressed D-PIGS have the potential for translation towards a safe and easily scalable single antigen-based tetravalent dengue vaccine.


Assuntos
Vacinas contra Dengue/imunologia , Engenharia Genética , Receptores de Imunoglobulina Polimérica/genética , Proteínas Recombinantes de Fusão/genética , Tonsila Faríngea/imunologia , Adjuvantes Imunológicos/genética , Animais , Anticorpos Neutralizantes/imunologia , Vacinas contra Dengue/genética , Feminino , Engenharia Genética/métodos , Humanos , Imunidade Celular , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Transgênicos , Tonsila Palatina/imunologia , Plantas Geneticamente Modificadas , Receptores de IgG/imunologia , Receptores de Imunoglobulina Polimérica/imunologia , Proteínas Recombinantes de Fusão/imunologia , Tabaco/genética
13.
Immune Netw ; 17(4): 228-236, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28860952

RESUMO

In the intestinal mucosal surface, microfold cells (M cells) are the representative gateway for the uptake of luminal antigens. At the same time, M cells are the primary infection site for pathogens invading mucosal surface for their infection. Although it is well recognized that many mucosal pathogens exploit the M cells for their infection, the mechanism to infect M cells utilized by pathogens is not clearly understood yet. In this study, we found that M cells expressing complement 5a (C5a) receptor (C5aR) also express Toll-like receptor (TLR) 1/2 and TLR4. Infection of Yersinia enterocolitica, an M cell-invading pathogen, synergistically regulated cyclic adenosine monophosphate-dependent protein kinase A (cAMP-PKA) signaling which are involved in signal crosstalk between C5aR and TLRs. In addition, Y. enterocolitica infection into M cells was enhanced by C5a treatment and this enhancement was abrogated by C5a antagonist treatment. Finally, Y. enterocolitica infection into M cells was unsuccessful in C5aR knock-out mice. Collectively, we suggest that exploit the crosstalk between C5aR and TLR signaling is one of infection mechanisms utilized by mucosal pathogens to infect M cells.

14.
Sci Rep ; 7(1): 3980, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28638068

RESUMO

The regional specialization of intestinal immune cells is affected by the longitudinal heterogeneity of environmental factors. Although the distribution of group 3 innate lymphoid cells (ILC3s) is well characterized in the lamina propria, it is poorly defined in Peyer's patches (PPs) along the intestine. Given that PP ILC3s are closely associated with mucosal immune regulation, it is important to characterize the regulatory mechanism of ILC3s. Here, we found that terminal ileal PPs of specific pathogen-free (SPF) mice have fewer NKp46+ ILC3s than jejunal PPs, while there was no difference in NKp46+ ILC3 numbers between terminal ileal and jejunal PPs in antibiotics (ABX)-treated mice. We also found that butyrate levels in the terminal ileal PPs of SPF mice were higher than those in the jejunal PPs of SPF mice and terminal ileal PPs of ABX-treated mice. The reduced number of NKp46+ ILC3s in terminal ileal PPs resulted in a decrease in Csf2 expression and, in turn, resulted in reduced regulatory T cells and enhanced antigen-specific T-cell proliferation. Thus, we suggest that NKp46+ ILC3s are negatively regulated by microbiota-derived butyrate in terminal ileal PPs and the reduced ILC3 frequency is closely associated with antigen-specific immune induction in terminal ileal PPs.


Assuntos
Butiratos/administração & dosagem , Microbioma Gastrointestinal , Íleo/imunologia , Jejuno/imunologia , Linfócitos/microbiologia , Nódulos Linfáticos Agregados/imunologia , Animais , Antígenos Ly/metabolismo , Butiratos/análise , Íleo/microbiologia , Jejuno/microbiologia , Linfócitos/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Nódulos Linfáticos Agregados/microbiologia
15.
Plant Biotechnol J ; 15(12): 1590-1601, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28421694

RESUMO

In order to enhance vaccine uptake by the immune cells in vivo, molecular engineering approach was employed to construct a polymeric immunoglobulin G scaffold (PIGS) that incorporates multiple copies of an antigen and targets the Fc gamma receptors on antigen-presenting cells. These self-adjuvanting immunogens were tested in the context of dengue infection, for which there is currently no globally licensed vaccine yet. Thus, the consensus domain III sequence (cEDIII) of dengue glycoprotein E was incorporated into PIGS and expressed in both tobacco plants and Chinese Ovary Hamster cells. Purified mouse and human cEDIII-PIGS were fractionated by HPLC into low and high molecular weight forms, corresponding to monomers, dimers and polymers. cEDIII-PIGS were shown to retain important Fc receptor functions associated with immunoglobulins, including binding to C1q component of the complement and the low affinity Fcγ receptor II, as well as to macrophage cells in vitro. These molecules were shown to be immunogenic in mice, with or without an adjuvant, inducing a high level IgG antibody response which showed a neutralizing potential against the dengue virus serotype 2. The cEDIII-PIGS also induced a significant cellular immune response, IFN-γ production and polyfunctional T cells in both the CD4+ and CD8+ compartments. This proof-of-principle study shows that the potent antibody Fc-mediated cellular functions can be harnessed to improve vaccine design, underscoring the potential of this technology to induce and modulate a broad-ranging immune response.


Assuntos
Vacinas contra Dengue/farmacologia , Cadeias Pesadas de Imunoglobulinas/genética , Engenharia de Proteínas/métodos , Proteínas Recombinantes/imunologia , Animais , Células CHO , Cricetulus , Vacinas contra Dengue/administração & dosagem , Vacinas contra Dengue/genética , Feminino , Regulação da Expressão Gênica de Plantas , Humanos , Cadeias Pesadas de Imunoglobulinas/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Testes de Neutralização , Plantas Geneticamente Modificadas/genética , Domínios Proteicos , Proteínas Recombinantes/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Tabaco/genética
16.
Chin J Nat Med ; 15(3): 192-201, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28411687

RESUMO

Red ginseng is a well-known alternative medicine with anti-inflammatory activity. It exerts pharmacological effects through the transformation of saponin into metabolites by intestinal microbiota. Given that intestinal microflora vary among individuals, the pharmacological effects of red ginseng likely vary among individuals. In order to produce homogeneously effective red ginseng, we prepared probiotic-fermented red ginseng and evaluated its activity using a dextran sulfate sodium (DSS)-induced colitis model in mice. Initial analysis of intestinal damage indicated that the administration of probiotic-fermented red ginseng significantly decreased the severity of colitis, compared with the control and the activity was higher than that induced by oral administration of ginseng powder or probiotics only. Subsequent analysis of the levels of serum IL-6 and TNF-α, inflammatory biomarkers that are increased at the initiation stage of colitis, were significantly decreased in probiotic-fermented red ginseng-treated groups in comparison to the control group. The levels of inflammatory cytokines and mRNAs for inflammatory factors in colorectal tissues were also significantly decreased in probiotic-fermented red ginseng-treated groups. Collectively, oral administration of probiotic-fermented red ginseng reduced the severity of colitis in a mouse model, suggesting that it can be used as a uniformly effective red ginseng product.


Assuntos
Colite/tratamento farmacológico , Lactobacillus plantarum/metabolismo , Panax/microbiologia , Extratos Vegetais/administração & dosagem , Probióticos/metabolismo , Administração Oral , Animais , Colite/induzido quimicamente , Colite/imunologia , Colo/efeitos dos fármacos , Colo/imunologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Feminino , Fermentação , Humanos , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Panax/química , Panax/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Pós/administração & dosagem , Pós/metabolismo , Fator de Necrose Tumoral alfa/imunologia
17.
Clin Exp Vaccine Res ; 6(1): 15-21, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28168169

RESUMO

Vaccination is the most successful immunological practice that improves the quality of human life and health. Vaccine materials include antigens of pathogens and adjuvants potentiating the effectiveness of vaccination. Vaccines are categorized using various criteria, including the vaccination material used and the method of administration. Traditionally, vaccines have been injected via needles. However, given that most pathogens first infect mucosal surfaces, there is increasing interest in the establishment of protective mucosal immunity, achieved by vaccination via mucosal routes. This review summarizes recent developments in mucosal vaccines and their associated adjuvants.

18.
J Immunol ; 198(2): 629-633, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27974458

RESUMO

Peyer's patches (PPs) are the major mucosal immune-inductive site, and germinal centers (GCs) in PPs determine the quality of the Abs produced. PP GCs are continuously induced by the gut microbiota, and their maintenance contributes to the induction of strong IgA responses to Ags. In this study, we investigated the role of formyl peptide receptor (FPR)-mediated signaling in the maintenance of PP GCs, because FPRs recognize the microbiota and initiate an innate immune response by chemotaxis. We found that follicular dendritic cells (FDCs), a key organizer of B cell follicles and GCs in mucosal immunity, express Fpr2. Additionally, Fpr2-mediated signaling in PP FDCs promoted Cxcl13 and B cell activating factor expression, as well as B cell proliferation and activation. Therefore, we suggest that Fpr2-mediated signaling in FDCs plays a key role in GC maintenance in PPs and results in an Ag-specific IgA response in the gut mucosal immune compartment.


Assuntos
Linfócitos B/imunologia , Células Dendríticas Foliculares/imunologia , Ativação Linfocitária/imunologia , Nódulos Linfáticos Agregados/imunologia , Receptores de Formil Peptídeo/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/imunologia , Citometria de Fluxo , Imunofluorescência , Centro Germinativo/imunologia , Imunidade nas Mucosas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/imunologia
19.
Pharm Biol ; 55(1): 317-323, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27927080

RESUMO

CONTEXT: Red ginseng (heat-processed Panax ginseng) is a well-known alternative medicine with pharmacological antidiabetic activity. It exerts pharmacological effects through the transformation of saponin into metabolites by the intestinal microbiota. Given that intestinal conditions and intestinal microflora vary among individuals, the pharmacological effects of orally administered red ginseng likely may vary among individuals. OBJECTIVE: To overcome this variation and produce homogeneously effective red ginseng, we evaluated the antidiabetic effects of probiotic-fermented red ginseng in a mouse model. MATERIALS AND METHODS: The antidiabetic efficacy of orally administered probiotic-fermented red ginseng was assessed in ICR mice after induction of diabetes using streptozotocin (170 mg/kg body weight). Samples were given orally for 8 weeks, and indicators involved in diabetic disorders such as body weight change, water intake, blood glucose, glucose tolerance and various biochemical parameters were determined. RESULTS: Oral administration of probiotic-fermented red ginseng significantly decreased the level of blood glucose of about 62.5% in the fasting state and induced a significant increase in glucose tolerance of about 10.2% compared to the control diabetic mice. Additionally, various indicators of diabetes and biochemical data (e.g., blood glycosylated haemoglobin level, serum concentrations of insulin, and α-amylase activity) showed a significant improvement in the diabetic conditions of the mice treated with probiotic-fermented red ginseng in comparison with those of control diabetic mice. DISCUSSION AND CONCLUSION: Our results demonstrate the antidiabetic effects of probiotic-fermented red ginseng in the streptozotocin-induced mouse diabetes model and suggest that probiotic-fermented red ginseng may be a uniformly effective red ginseng product.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Fermentação , Hipoglicemiantes/farmacologia , Panax/metabolismo , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Probióticos , Estreptozocina , Administração Oral , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Hemoglobina A Glicada/metabolismo , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/metabolismo , Insulina/sangue , Masculino , Camundongos Endogâmicos ICR , Fitoterapia , Extratos Vegetais/administração & dosagem , Plantas Medicinais , Pós , Fatores de Tempo , alfa-Amilases/metabolismo
20.
Int Immunopharmacol ; 43: 91-98, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27987467

RESUMO

Studies have been focused on natural products with antibacterial and anti-inflammatory activities, such as fucoidan. Many in vivo studies have evaluated the effect of fucoidan on tumor growth, diabetes, obesity, ischemia reperfusion, and oxidative stress. However, the effects of fucoidan on bacteria-induced gingival inflammation and periodontitis have not been reported. We previously characterized the anti-inflammatory effect of fucoidan in vitro. Here, we confirmed the anti-inflammatory activity of fucoidan in a macrophage cell line in terms of its inhibition of the expression of inflammatory mediators and pro-inflammatory cytokines. Additionally, we confirmed the ability of fucoidan to inhibit gingival inflammation, expression of pro-inflammatory cytokines, and neutrophil recruitment in the gingival tissue of mice injected with LPS prepared from P. gingivalis. Interestingly, however, fucoidan did not inhibit the expression of pro-inflammatory cytokines in a P. gingivalis-infected mouse model of periodontitis. Additionally, fucoidan treatment did not lead to clearance of P. gingivalis or improvement of P. gingivalis infection-mediated bone loss in the periodontitis model. We conclude that fucoidan exerts anti-inflammatory effects in vitro and in vivo, together with a limited antibacterial effect in vivo.


Assuntos
Anti-Inflamatórios/uso terapêutico , Infecções por Bacteroidaceae/tratamento farmacológico , Gengiva/efeitos dos fármacos , Gengivite/tratamento farmacológico , Neutrófilos/efeitos dos fármacos , Periodontite/tratamento farmacológico , Polissacarídeos/uso terapêutico , Porphyromonas gingivalis/imunologia , Animais , Movimento Celular/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Gengiva/imunologia , Gengiva/microbiologia , Gengivite/induzido quimicamente , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos , Neutrófilos/imunologia , Células RAW 264.7
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