Immune markers and correlates of protection for vaccine induced immune responses

DEFF Research Database (Denmark)

Thakur, Aneesh; Pedersen, Lasse Eggers; Jungersen, Gregers

2012-01-01

of an appropriate humoral response currently remain the best validated correlates of protective immunity after vaccination. Despite advancements in the field of immunology over the past few decades currently there are, however, no sufficiently validated immune correlates of vaccine induced protection against......-specific production of interferon-gamma (IFN-γ) has been promoted as a quantitative marker of protective cell-mediated immune responses over the past couple of decades. More recently, however, evidence from several infections has pointed towards the quality of the immune response, measured through increased levels...... of antigen-specific polyfunctional T cells capable of producing a triad of relevant cytokines, as a better correlate of sustained protective immunity against this type of infections. Also the possibilities to measure antigen-specific cytotoxic T cells (CTL) during infection or in response to vaccination...

Sporothrix schenckii Immunization, but Not Infection, Induces Protective Th17 Responses Mediated by Circulating Memory CD4+ T Cells

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Alberto García-Lozano

2018-06-01

Full Text Available Sporotrichosis is a chronic subcutaneous mycosis caused by the Sporothrix schenckii species complex and it is considered an emerging opportunistic infection in countries with tropical and subtropical climates. The host’s immune response has a main role in the development of this disease. However, it is unknown the features of the memory cellular immune response that could protect against the infection. Our results show that i.d. immunization in the ears of mice with inactivated S. schenckii conidia (iC combined with the cholera toxin (CT induces a cellular immune response mediated by circulating memory CD4+ T cells, which mainly produce interleukin 17 (IL-17. These cells mediate a strong delayed-type hypersensitivity (DTH reaction. Systemic and local protection against S. schenckii was mediated by circulating CD4+ T cells. In contrast, the infection induces a potent immune response in the skin mediated by CD4+ T cells, which have an effector phenotype that preferentially produce interferon gamma (IFN-γ and mediate a transitory DTH reaction. Our findings prove the potential value of the CT as a potent skin adjuvant when combined with fungal antigens, and they also have important implications for our better understanding of the differences between the memory immune response induced by the skin immunization and those induced by the infection; this knowledge enhances our understanding of how a protective immune response against a S. schenckii infection is developed.

An immunoproteomic approach revealing peptides from Sporothrix brasiliensis that induce a cellular immune response in subcutaneous sporotrichosis.

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de Almeida, José Roberto Fogaça; Jannuzzi, Grasielle Pereira; Kaihami, Gilberto Hideo; Breda, Leandro Carvalho Dantas; Ferreira, Karen Spadari; de Almeida, Sandro Rogério

2018-03-08

Sporothrix brasiliensis is the most virulent fungus of the Sporothrix complex and is the main species recovered in the sporotrichosis zoonotic hyperendemic area in Rio de Janeiro. A vaccine against S. brasiliensis could improve the current sporotrichosis situation. Here, we show 3 peptides from S. brasiliensis immunogenic proteins that have a higher likelihood for engaging MHC-class II molecules. We investigated the efficiency of the peptides as vaccines for preventing subcutaneous sporotrichosis. In this study, we observed a decrease in lesion diameters in peptide-immunized mice, showing that the peptides could induce a protective immune response against subcutaneous sporotrichosis. ZR8 peptide is from the GP70 protein, the main antigen of the Sporothrix complex, and was the best potential vaccine candidate by increasing CD4 + T cells and higher levels of IFN-γ, IL-17A and IL-1β characterizing a strong cellular immune response. This immune environment induced a higher number of neutrophils in lesions that are associated with fungus clearance. These results indicated that the ZR8 peptide induces a protective immune response against subcutaneous sporotrichosis and is a vaccine candidate against S. brasiliensis infection.

pH-Responsive Micelle-Based Cytoplasmic Delivery System for Induction of Cellular Immunity

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Eiji Yuba

2017-11-01

Full Text Available (1 Background: Cytoplasmic delivery of antigens is crucial for the induction of cellular immunity, which is an important immune response for the treatment of cancer and infectious diseases. To date, fusogenic protein-incorporated liposomes and pH-responsive polymer-modified liposomes have been used to achieve cytoplasmic delivery of antigen via membrane rupture or fusion with endosomes. However, a more versatile cytoplasmic delivery system is desired for practical use. For this study, we developed pH-responsive micelles composed of dilauroyl phosphatidylcholine (DLPC and deoxycholic acid and investigated their cytoplasmic delivery performance and immunity-inducing capability. (2 Methods: Interaction of micelles with fluorescence dye-loaded liposomes, intracellular distribution of micelles, and antigenic proteins were observed. Finally, antigen-specific cellular immune response was evaluated in vivo using ELIspot assay. (3 Results: Micelles induced leakage of contents from liposomes via lipid mixing at low pH. Micelles were taken up by dendritic cells mainly via macropinocytosis and delivered ovalbumin (OVA into the cytosol. After intradermal injection of micelles and OVA, OVA-specific cellular immunity was induced in the spleen. (4 Conclusions: pH-responsive micelles composed of DLPC and deoxycholic acid are promising as enhancers of cytosol delivery of antigens and the induction capability of cellular immunity for the treatment of cancer immunotherapy and infectious diseases.

Humoral and cellular immunity in women with infertility (dynamic observation after Chernobyl accident)

International Nuclear Information System (INIS)

Dubchak, A.Je.

2000-01-01

The influence of low-dose radiation on the state of humoral and cellular immunity in women with infertility of inflammatory origin during a dynamic study was studied. The data of the dynamic study of cellular and humoral immunity in women with inflammatory infertility evacuated from Chernobyl and Pripyat and in those constantly residing on the controlled territories compared to those living in Poltava, the differences suggesting unfavorable influence of harmful factors (including low-dose radiation) on the organism of the woman have been revealed. In the evacuated women the changes in cellular and humoral immunity were observed during the first years after the accident, while in those residing in the controlled territories 4-5 years after the accident

The evolutionarily conserved mediator subunit MDT-15/MED15 links protective innate immune responses and xenobiotic detoxification.

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Read Pukkila-Worley

2014-05-01

Full Text Available Metazoans protect themselves from environmental toxins and virulent pathogens through detoxification and immune responses. We previously identified a small molecule xenobiotic toxin that extends survival of Caenorhabditis elegans infected with human bacterial pathogens by activating the conserved p38 MAP kinase PMK-1 host defense pathway. Here we investigate the cellular mechanisms that couple activation of a detoxification response to innate immunity. From an RNAi screen of 1,420 genes expressed in the C. elegans intestine, we identified the conserved Mediator subunit MDT-15/MED15 and 28 other gene inactivations that abrogate the induction of PMK-1-dependent immune effectors by this small molecule. We demonstrate that MDT-15/MED15 is required for the xenobiotic-induced expression of p38 MAP kinase PMK-1-dependent immune genes and protection from Pseudomonas aeruginosa infection. We also show that MDT-15 controls the induction of detoxification genes and functions to protect the host from bacteria-derived phenazine toxins. These data define a central role for MDT-15/MED15 in the coordination of xenobiotic detoxification and innate immune responses.

The evolutionarily conserved mediator subunit MDT-15/MED15 links protective innate immune responses and xenobiotic detoxification.

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Pukkila-Worley, Read; Feinbaum, Rhonda L; McEwan, Deborah L; Conery, Annie L; Ausubel, Frederick M

2014-05-01

Metazoans protect themselves from environmental toxins and virulent pathogens through detoxification and immune responses. We previously identified a small molecule xenobiotic toxin that extends survival of Caenorhabditis elegans infected with human bacterial pathogens by activating the conserved p38 MAP kinase PMK-1 host defense pathway. Here we investigate the cellular mechanisms that couple activation of a detoxification response to innate immunity. From an RNAi screen of 1,420 genes expressed in the C. elegans intestine, we identified the conserved Mediator subunit MDT-15/MED15 and 28 other gene inactivations that abrogate the induction of PMK-1-dependent immune effectors by this small molecule. We demonstrate that MDT-15/MED15 is required for the xenobiotic-induced expression of p38 MAP kinase PMK-1-dependent immune genes and protection from Pseudomonas aeruginosa infection. We also show that MDT-15 controls the induction of detoxification genes and functions to protect the host from bacteria-derived phenazine toxins. These data define a central role for MDT-15/MED15 in the coordination of xenobiotic detoxification and innate immune responses.

The effect of infectious dose on humoral and cellular immune responses in Chlamydophila caviae primary ocular infection.

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Ana Filipovic

Full Text Available Following infection, the balance between protective immunity and immunopathology often depends on the initial infectious load. Several studies have investigated the effect of infectious dose; however, the mechanism by which infectious dose affects disease outcomes and the development of a protective immune response is not known. The aim of this study was to investigate how the infectious dose modulates the local and systemic humoral and the cellular immune responses during primary ocular chlamydial infection in the guinea pig animal model. Guinea pigs were infected by ocular instillation of a Chlamydophila caviae-containing eye solution in the conjunctival sac in three different doses: 1×102, 1×104, and 1×106 inclusion forming units (IFUs. Ocular pathology, chlamydial clearance, local and systemic C. caviae-specific humoral and cellular immune responses were assessed. All inocula of C. caviae significantly enhanced the local production of C. caviae-specific IgA in tears, but only guinea pigs infected with the higher doses showed significant changes in C. caviae-specific IgA levels in vaginal washes and serum. On complete resolution of infection, the low dose of C. caviae did not alter the ratio of CD4+ and CD8+ cells within guinea pigs' submandibular lymph node (SMLN lymphocytes while the higher doses increased the percentages of CD4+ and CD8+ cells within the SMLN lymphocytes. A significant negative correlation between pathology intensity and the percentage of CD4+ and CD8+ cells within SMLN lymphocyte pool at selected time points post-infection was recorded for both 1×104, and 1×106 IFU infected guinea pigs. The relevance of the observed dose-dependent differences on the immune response should be further investigated in repeated ocular chlamydial infections.

Skin innate immune system

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Berna Aksoy

2013-06-01

Full Text Available All multicellular organisms protect themselves from external universe and microorganisms by innate immune sytem that is constitutively present. Skin innate immune system has several different components composed of epithelial barriers, humoral factors and cellular part. In this review information about skin innate immune system and its components are presented to the reader. Innate immunity, which wasn’t adequately interested in previously, is proven to provide a powerfull early protection system, control many infections before the acquired immunity starts and directs acquired immunity to develop optimally

Studies on the transfer of protective immunity with lymphoid cells from mice immune to malaria sporozoites

International Nuclear Information System (INIS)

Verhave, J.P.; Strickland, G.T.; Jaffe, H.A.; Ahmed, A.

1978-01-01

In an effort to understand the mechanisms involved in the protective immunity to malarial sporozoites, an A/J mouse/Plasmodium berghei model was studied. Protective immunity could consistently be adoptively transferred only by using sublethal irradiation of recipients (500 R); a spleen equivalent (100 x 10 6 ) of donor cells from immune syngeneic mice; and a small booster immunization (1 x 10 4 ) of recipients with irradiation-attenuated sporozoites. Recipient animals treated in this manner were protected from lethal challenge with 1 x 10 4 nonattenuated sporozoites. Immune and nonimmune serum and spleen cells from nonimmune animals did not protect recipient mice. Fewer immune spleen cells (50 x 10 6 ) protected some recipients. In vitro treatment of immune spleen cells with anti-theta sera and complement abolished their ability to transfer protection. This preliminary study suggests that protective sporozoite immunity can be transferred with cells, and that it is T cell dependent

Activity against Mycobacterium tuberculosis with concomitant induction of cellular immune responses by a tetraaza-macrocycle with acetate pendant arms.

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David, S; Ordway, D; Arroz, M J; Costa, J; Delgado, R

2001-01-01

The novel tetraaza-macrocyclic compound 3,7,11-tris(carboxymethyl)-3,7,11,17-tetraaza-bicyclo[11.3.1]heptadeca-1(17),13,15-triene, abbreviated as ac3py14, was investigated for its activity against Mycobacterium tuberculosis and for induction of protective cellular immune responses. Perspective results show that ac3py14 and its Fe3+ 1:1 complex, [Fe(ac3py14)], inhibited radiometric growth of several strains of M. tuberculosis. Inhibition with 25 microg/mL varied from 99% for H37Rv to 80% and above for multiple drug-resistant clinical isolates. The capacity of ac3py14 to elicit a beneficial immune response without cellular apoptosis was assessed and compared to the effects of virulent M. tuberculosis. The present study produces evidence that after stimulation with ac3py14 there was significant production of interferon gamma (IFN-gamma), whereas the production of interleukin-5 (IL-5) remained low, and there was development of a memory population (CD45RO). The level of binding of Annexin V, a marker of apoptosis, was not sufficient to result in toxic effects toward alphabeta and gammadelta T cells and CD14+ macrophages. This preliminary study is the first report of a compound that simultaneously exerts an inhibitory effect against M. tuberculosis and induces factors associated with protective immune responses.

Differential protective effects of immune lymphoid cells against transplanted line Ib leukemia and immune polioencephalomyelitis

International Nuclear Information System (INIS)

Duffey, P.S.; Lukasewycz, O.A.; Olson, D.S.; Murphy, W.H.

1978-01-01

The capacity of immune cells obtained from the major lymphoid compartments to protect C58 mice from transplanted line Ib leukemia, and from an age-dependent autoimmune CNS disease (immune polioencephalomyelitis = IPE) elicited by immunizing old C58 mice with inactivated Ib cells was quantified. Cells used for comparative adoptive protection tests were harvested from the major lymphoid compartments 14 to 15 days after young C58 mice were immunized with inactivated Ib cell preparations. Regression curves were plotted from survival data and the log 10 PD 50 values were determined. Immune spleen (ISC) and peritoneal cells (IPEC) were significantly more protective against transplanted Ib cells than immune lymph node (ILNC), thymic (ITC), and marrow cells (IMC). In contrast, IPEC and IMC were not protective against IPE and ITC were only marginally protective. ILNC afforded significant protection to transplantable leukemia but were only marginally protective to IPE. When ISC were treated with anti-thy 1.2 serum and complement, protection against transplanted leukemia and IPE was reduced > 99%. When donors of immune lymphoid cells were treated with 12.5 mg of cortisone acetate daily for 2 days before lymphoid cells were harvested, protection against transplanted Ib cells by ISC was reduced by approximately 90% whereas protection against IPE was totally eliminated. Considered together, these results indicate that the protective mechanisms to transplantable leukemia and IPE differ significantly in the same indicator mouse strain

Immune response to soluble exoantigens of Plasmodium falciparum may contribute to both pathogenesis and protection in clinical malaria: evidence from a longitudinal, prospective study of semi-immune African children

DEFF Research Database (Denmark)

Riley, E M; Jakobsen, P H; Allen, S J

1991-01-01

Some soluble exoantigens of Plasmodium have lipopolysaccharide (LPS)-like properties and are believed to contribute to the pathogenesis of acute malaria. We have studied cellular and humoral immune responses to several purified exoantigens of Plasmodium falciparum in a cohort of children and comp......Some soluble exoantigens of Plasmodium have lipopolysaccharide (LPS)-like properties and are believed to contribute to the pathogenesis of acute malaria. We have studied cellular and humoral immune responses to several purified exoantigens of Plasmodium falciparum in a cohort of children...... and compared these responses with their subsequent susceptibility to malaria infection and clinical disease. We found no evidence that either lymphoproliferative or interferon-gamma (IFN-gamma) responses to these antigens were associated with protective immunity. On the contrary, children whose cells produced...

Hantavirus Gc induces long-term immune protection via LAMP-targeting DNA vaccine strategy.

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Jiang, Dong-Bo; Zhang, Jin-Peng; Cheng, Lin-Feng; Zhang, Guan-Wen; Li, Yun; Li, Zi-Chao; Lu, Zhen-Hua; Zhang, Zi-Xin; Lu, Yu-Chen; Zheng, Lian-He; Zhang, Fang-Lin; Yang, Kun

2018-02-01

Hemorrhagic fever with renal syndrome (HFRS) occurs widely throughout Eurasia. Unfortunately, there is no effective treatment, and prophylaxis remains the best option against the major pathogenic agent, hantaan virus (HTNV), which is an Old World hantavirus. However, the absence of cellular immune responses and immunological memory hampers acceptance of the current inactivated HFRS vaccine. Previous studies revealed that a lysosome-associated membrane protein 1 (LAMP1)-targeting strategy involving a DNA vaccine based on the HTNV glycoprotein Gn successfully conferred long-term immunity, and indicated that further research on Gc, another HTNV antigen, was warranted. Plasmids encoding Gc and lysosome-targeted Gc, designated pVAX-Gc and pVAX-LAMP/Gc, respectively, were constructed. Proteins of interest were identified by fluorescence microscopy following cell line transfection. Five groups of 20 female BALB/c mice were subjected to the following inoculations: inactivated HTNV vaccine, pVAX-LAMP/Gc, pVAX-Gc, and, as the negative controls, pVAX-LAMP or the blank vector pVAX1. Humoral and cellular immunity were assessed by enzyme-linked immunosorbent assays (ELISAs) and 15-mer peptide enzyme-linked immunospot (ELISpot) epitope mapping assays. Repeated immunization with pVAX-LAMP/Gc enhanced adaptive immune responses, as demonstrated by the specific and neutralizing antibody titers and increased IFN-γ production. The inactivated vaccine induced a comparable humoral reaction, but the negative controls only elicited insignificant responses. Using a mouse model of HTNV challenge, the in vivo protection conferred by the inactivated vaccine and Gc-based constructs (with/without LAMP recombination) was confirmed. Evidence of pan-epitope reactions highlighted the long-term cellular response to the LAMP-targeting strategy, and histological observations indicated the safety of the LAMP-targeting vaccines. The long-term protective immune responses induced by pVAX-LAMP/Gc may be

Friends and foes of tuberculosis: modulation of protective immunity.

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Brighenti, Susanna; Joosten, Simone A

2018-05-27

Protective immunity in tuberculosis (TB) is subject of debate in the TB research community, as this is key to fully understand TB pathogenesis and to develop new promising tools for TB diagnosis and prognosis as well as a more efficient TB vaccine. IFN-γ producing CD4 + T cells are key in TB control, but may not be sufficient to provide protection. Additional subsets have been identified that contribute to protection such as multifunctional and cytolytic T cell subsets, including classical and non-classical T cells as well as novel innate immune cell subsets resulting from trained immunity. However, to define protective immune responses against TB, the complexity of balancing TB immunity also has to be considered. In this review, insights in effector cell immunity and how this is modulated by regulatory cells, associated comorbidities and the host microbiome is discussed. We systematically map how different suppressive immune cell subsets may affect effector cell responses at the local site of infection. We also dissect how common co-morbidities such as HIV, helminthes and diabetes may bias protective TB immunity towards pathogenic and regulatory responses. Finally, also the composition and diversity of the microbiome in the lung and gut could affect host TB immunity. Understanding these various aspects of the immunological balance in the human host is fundamental to prevent TB infection and disease. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Gold nanoparticles conjugating recombinant influenza hemagglutinin trimers and flagellin enhanced mucosal cellular immunity.

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Wang, Chao; Zhu, Wandi; Luo, Yuan; Wang, Bao-Zhong

2018-04-09

The immunogenicity of subunit vaccines can be augmented by formulating them into nanoparticles. We conjugated recombinant trimetric influenza A/Aichi/2/68(H3N2) hemagglutinin (HA) onto functionalized gold nanoparticles (AuNPs) surfaces in a repetitive, oriented configuration. To further improve the immunogenicity, we generated Toll-like receptor 5 (TLR5) agonist flagellin (FliC)-coupled AuNPs as particulate adjuvants. Intranasal immunizations with an AuNP-HA and AuNP-FliC particle mixture elicited strong mucosal and systemic immune responses that protected hosts against lethal influenza challenges. Compared with the AuNP-HA alone group, the addition of AuNP-FliC improved mucosal B cell responses as characterized by elevated influenza specific IgA and IgG levels in nasal, tracheal, and lung washes. AuNP-HA/AuNP-FliC also stimulated antigen-specific interferon-γ (IFN-γ)-secreting CD4 + cell proliferation and induced strong effector CD8 + T cell activation. Our results indicate that intranasal co-delivery of antigen and adjuvant-displaying AuNPs enhanced vaccine efficacy by inducing potent cellular immune responses. Copyright © 2018. Published by Elsevier Inc.

Smallpox vaccines: targets of protective immunity.

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Moss, Bernard

2011-01-01

The eradication of smallpox, one of the great triumphs of medicine, was accomplished through the prophylactic administration of live vaccinia virus, a comparatively benign relative of variola virus, the causative agent of smallpox. Nevertheless, recent fears that variola virus may be used as a biological weapon together with the present susceptibility of unimmunized populations have spurred the development of new-generation vaccines that are safer than the original and can be produced by modern methods. Predicting the efficacy of such vaccines in the absence of human smallpox, however, depends on understanding the correlates of protection. This review outlines the biology of poxviruses with particular relevance to vaccine development, describes protein targets of humoral and cellular immunity, compares animal models of orthopoxvirus disease with human smallpox, and considers the status of second- and third-generation smallpox vaccines. Published 2010. This article is a US Government work and is in the public domain in the USA.

Pathogen-mimicking vaccine delivery system designed with a bioactive polymer (inulin acetate) for robust humoral and cellular immune responses.

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Kumar, Sunny; Kesharwani, Siddharth S; Kuppast, Bhimanna; Bakkari, Mohammed Ali; Tummala, Hemachand

2017-09-10

New and improved vaccines are needed against challenging diseases such as malaria, tuberculosis, Ebola, influenza, AIDS, and cancer. The majority of existing vaccine adjuvants lack the ability to significantly stimulate the cellular immune response, which is required to prevent the aforementioned diseases. This study designed a novel particulate based pathogen-mimicking vaccine delivery system (PMVDS) to target antigen-presenting-cells (APCs) such as dendritic cells. The uniqueness of PMVDS is that the polymer used to prepare the delivery system, Inulin Acetate (InAc), activates the innate immune system. InAc was synthesized from the plant polysaccharide, inulin. PMVDS provided improved and persistent antigen delivery to APCs as an efficient vaccine delivery system, and simultaneously, activated Toll-Like Receptor-4 (TLR-4) on APCs to release chemokine's/cytokines as an immune-adjuvant. Through this dual mechanism, PMVDS robustly stimulated both the humoral (>32 times of IgG1 levels vs alum) and the cell-mediated immune responses against the encapsulated antigen (ovalbumin) in mice. More importantly, PMVDS stimulated both cytotoxic T cells and natural killer cells of cell-mediated immunity to provide tumor (B16-ova-Melanoma) protection in around 40% of vaccinated mice and significantly delayed tumor progression in rest of the mice. PMVDS is a unique bio-active vaccine delivery technology with broader applications for vaccines against cancer and several intracellular pathogens, where both humoral and cellular immune responses are desired. Copyright © 2017 Elsevier B.V. All rights reserved.

Commensal–dendritic-cell interaction specifies a unique protective skin immune signature

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Naik, Shruti; Bouladoux, Nicolas; Linehan, Jonathan L.; Han, Seong-Ji; Harrison, Oliver J.; Wilhelm, Christoph; Conlan, Sean; Himmelfarb, Sarah; Byrd, Allyson L.; Deming, Clayton; Quinones, Mariam; Brenchley, Jason M.; Kong, Heidi H.; Tussiwand, Roxanne; Murphy, Kenneth M.; Merad, Miriam; Segre, Julia A; Belkaid, Yasmine

2015-01-01

The skin represents the primary interface between the host and the environment. This organ is also home to trillions of microorganisms that play an important role in tissue homeostasis and local immunity1–4. Skin microbial communities are highly diverse and can be remodelled over time or in response to environmental challenges5–7. How, in the context of this complexity, individual commensal microorganisms may differentially modulate skin immunity and the consequences of these responses for tissue physiology remains unclear. Here we show that defined commensals dominantly affect skin immunity and identify the cellular mediators involved in this specification. In particular, colonization with Staphylococcus epidermidis induces IL-17A+ CD8+ T cells that home to the epidermis, enhance innate barrier immunity and limit pathogen invasion. Commensal-specific T-cell responses result from the coordinated action of skin-resident dendritic cell subsets and are not associated with inflammation, revealing that tissue-resident cells are poised to sense and respond to alterations in microbial communities. This interaction may represent an evolutionary means by which the skin immune system uses fluctuating commensal signals to calibrate barrier immunity and provide heterologous protection against invasive pathogens. These findings reveal that the skin immune landscape is a highly dynamic environment that can be rapidly and specifically remodelled by encounters with defined commensals, findings that have profound implications for our understanding of tissue-specific immunity and pathologies. PMID:25539086

Intranasal immunization with fusion protein MrpH·FimH and MPL adjuvant confers protection against urinary tract infections caused by uropathogenic Escherichia coli and Proteus mirabilis.

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Habibi, Mehri; Asadi Karam, Mohammad Reza; Shokrgozar, Mohammad Ali; Oloomi, Mana; Jafari, Anis; Bouzari, Saeid

2015-04-01

Urinary tract infections (UTIs) caused by Uropathogenic Escherichia coli (UPEC) and Proteus mirabilis are among the most common infections in the world. Currently there are no vaccines available to confer protection against UTI in humans. In this study, the immune responses and protection of FimH of UPEC with MrpH antigen of P. mirabilis in different vaccine formulations with and without MPL adjuvant were assessed. Mice intranasally immunized with the novel fusion protein MrpH·FimH induced a significant increase in IgG and IgA in serum, nasal wash, vaginal wash, and urine samples. Mice immunized with fusion MrpH·FimH also showed a significant boost in cellular immunity. Addition of MPL as the adjuvant enhanced FimH and MrpH specific humoral and cellular responses in both systemic and mucosal samples. Vaccination with MrpH·FimH alone or in combination with MPL showed the highest efficiency in clearing bladder and kidney infections in mice challenged with UPEC and P. mirabilis. These findings may indicate that the protection observed correlates with the systemic, mucosal and cellular immune responses induced by vaccination with these preparations. Our data suggest MrpH·FimH fusion protein with or without MPL as adjuvant could be potential vaccine candidates for elimination of UPEC and P. mirabilis. These data altogether are promising and these formulations are good candidates for elimination of UPEC and P. mirabilis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Balancing immune protection and immune pathology by CD8+ T cell responses to influenza infection

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Susu eDuan

2016-02-01

Full Text Available Influenza A virus (IAV is a significant human pathogen causing annual epidemics and periodic pandemics. CD8+ cytotoxic T lymphocyte (CTL-mediated immunity contributes to clearance of virus-infected cells; CTL immunity targeting the conserved internal proteins of IAVs is a key protection mechanism when neutralizing antibodies are absent during heterosubtypic IAV infection. However, CTL infiltration into the airways, their cytotoxicity, and the effects of produced pro-inflammatory cytokines can cause severe lung tissue injury, thereby contributing to immunopathology. Studies have discovered complicated and exquisite stimulatory and inhibitory mechanisms that regulate CTL magnitude and effector activities during IAV infection. Here, we review the state of knowledge on the roles of IAV-specific CTLs in immune protection and immunopathology during IAV infection in animal models, highlighting the key findings of various requirements and constraints regulating the balance of immune protection and pathology involved in CTL immunity. We also discuss the evidence of cross-reactive CTL immunity as a positive correlate of cross-subtype protection during secondary IAV infection in both animal and human studies. We argue that the effects of CTL immunity on protection and immunopathology depend on multiple layers of host and viral factors, including complex host mechanisms to regulate CTL magnitude and effector activity, the pathogenic nature of the IAV, the innate response milieu, and the host historical immune context of influenza infection. Future efforts are needed to further understand these key host and viral factors, especially to differentiate those that constrain optimally effective CTL anti-viral immunity from those necessary to restrain CTL-mediated nonspecific immunopathology in the various contexts of IAV infection, in order to develop better vaccination and therapeutic strategies for modifying protective CTL immunity.

Persistent Low-Level Replication of SIVΔnef Drives Maturation of Antibody and CD8 T Cell Responses to Induce Protective Immunity against Vaginal SIV Infection.

Science.gov (United States)

Adnan, Sama; Reeves, R Keith; Gillis, Jacqueline; Wong, Fay E; Yu, Yi; Camp, Jeremy V; Li, Qingsheng; Connole, Michelle; Li, Yuan; Piatak, Michael; Lifson, Jeffrey D; Li, Wenjun; Keele, Brandon F; Kozlowski, Pamela A; Desrosiers, Ronald C; Haase, Ashley T; Johnson, R Paul

2016-12-01

Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef vaccination were protected, as defined by either apparent sterile protection or significant suppression of viremia in infected animals. Multiple parameters of CD8 T cell function temporally correlated with maturation of protection, including polyfunctionality, phenotypic differentiation, and redistribution to gut and lymphoid tissues. Importantly, we also demonstrate the induction of a tissue-resident memory population of SIV-specific CD8 T cells in the vaginal mucosa, which was dependent on ongoing low-level antigenic stimulation. Moreover, we show that vaginal and serum antibody titers inversely correlated with post-challenge peak viral load, and we correlate the accumulation and affinity maturation of the antibody response to the duration of the vaccination period as well as to the SIVΔnef antigenic load. In conclusion, maturation of SIVΔnef-induced CD8 T cell and antibody responses, both propelled by viral persistence in the gut mucosa and secondary lymphoid tissues, results in protective immune responses that are able to interrupt viral transmission at mucosal portals of entry as well as potential sites of viral dissemination.

Rapid Assay of Cellular Immunity in Q Fever.

Science.gov (United States)

1995-10-01

measuring CMI Measurement of CMI has been accomplished by many different methods both in vitro and in vivo (Clough & Roth , 1995). Some methods are...also become chronic with endocarditis as the main symptom and can result in death. Vaccines are being developed and have shown encouraging success in...rickettsial diseases with strong cellular immune responses following infection. The efficacy of a vaccine against Rocky Mountain spotted fever, R

HUMORAL AND CELLULAR IMMUNITY PARAMETERS IN CHILDREN BEFORE AND AFTER ADENOTONSILLECTOMY

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M. H. Baradaranfar

2007-08-01

Full Text Available Adenoids and tonsils are active lymphoid organs and play an important role ‎against invading antigens of upper aerodigestive tract in children. ‎The present study analyzes the changes in cellular and humoral immunity of children six ‎months after adenotonsillectomy. The study population consisted of 30 children whit chronic adenotonsillar hypertrophy and 30 age-matched healthy children. ‎In all children serum level of IgM and IgG, percentage of T lymphocytes (CD3, T ‎helper cells (CD4, T cytotoxic ‎cells (CD8 and B lymphocytes (CD20 were measured before surgery. These parameters were ‎remeasured in patients 6 months after adenotonsillectomy. ‎Before the operation, a reduction in percentage of T lymphocytes (CD3,TCD4,TC8 ‎and B CD20 was seen compared to control group. This reduction was only significant in T ‎lymphocytes (CD3.The serum IgM and IgG levels were not different in two groups. Six months after ‎operation, the percentage of lymphocytes T CD3, T CD8 and BCD20 was increased and ‎reached the control group. The IgM level was also significantly decreased in patients after ‎operation. ‎Our results indicate that cellular and humoral immunity decreases in children ‎with chronic adenotonsiller hypertrophy preoperatively and increases to healthy children ‎level, six months postoperatively. It means that chronic adenotosillar hypertrophy affect ‎some parameters of cellular and humoral immunity and adenotonsillectomy by removing ‎chronic stimulations and reverses these changes without any negative effect on immune ‎function of patients.

Giardia-specific cellular immune responses in post-giardiasis chronic fatigue syndrome.

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Hanevik, Kurt; Kristoffersen, Einar; Mørch, Kristine; Rye, Kristin Paulsen; Sørnes, Steinar; Svärd, Staffan; Bruserud, Øystein; Langeland, Nina

2017-01-28

The role of pathogen specific cellular immune responses against the eliciting pathogen in development of post-infectious chronic fatigue syndrome (PI-CFS) is not known and such studies are difficult to perform. The aim of this study was to evaluate specific anti-Giardia cellular immunity in cases that developed CFS after Giardia infection compared to cases that recovered well. Patients reporting chronic fatigue in a questionnaire study three years after a Giardia outbreak were clinically evaluated five years after the outbreak and grouped according to Fukuda criteria for CFS and idiopathic chronic fatigue. Giardia specific immune responses were evaluated in 39 of these patients by proliferation assay, T cell activation and cytokine release analysis. 20 Giardia exposed non-fatigued individuals and 10 healthy unexposed individuals were recruited as controls. Patients were clinically classified into CFS (n = 15), idiopathic chronic fatigue (n = 5), fatigue from other causes (n = 9) and recovered from fatigue (n = 10). There were statistically significant antigen specific differences between these Giardia exposed groups and unexposed controls. However, we did not find differences between the Giardia exposed fatigue classification groups with regard to CD4 T cell activation, proliferation or cytokine levels in 6 days cultured PBMCs. Interestingly, sCD40L was increased in patients with PI-CFS and other persons with fatigue after Giardia infection compared to the non-fatigued group, and correlated well with fatigue levels at the time of sampling. Our data show antigen specific cellular immune responses in the groups previously exposed to Giardia and increased sCD40L in fatigued patients.

Cellular Immunity State of Protein-deficient Rats with the Toxic Liver Injury

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O.N. Voloshchuk

2017-05-01

Full Text Available Studies on the role of immunity mechanisms in the emergence and maintenance of inflammatory and destructive processes in the liver under toxic hepatitis and nutrient deficiency are topical. The aim of research – to study the quantitative content and functional activity of leukocytes under the conditions of acetaminophen-induced hepatitis on the background of nutritional protein deficiency. The most pronounced changes in cell-mediated immunity are observed in protein-deficient animals with toxic hepatitis. The pronounced defects of both specific and non-specific cellular immunity were manifested by the leukocytosis, increase number of segmented neutrophils in blood serum against decrease their phagocytic index and phagocytic number, reduction of total lymphocyte number, and simultaneously lowering of T- and B-lymphocytes was established under the conditions of acetaminophen-induced hepatotoxicity on the background of protein deficiency. Installed changes indicate the defective formation of functional immunity state which can manifest by decrease the body’s ability to carry out the reaction of cellular and humoral immunity. Research results may be used for the rationale of therapeutic approaches to the elimination and correction of the consequences of immunological status disturbances under the conditions of acetaminophen-induced hepatitis, aggravated by the alimentary protein deprivation.

Cellular immune response in prognosis of Bell's palsy and its ...

African Journals Online (AJOL)

Objective: To determine the cellular immune response in Bell's palsy (BP) and its prognostic value in relation to clinical and electrophysiological findings. Methods: Twenty patients with BP were subjected to: Facial nerve paralysis assessment according to House–Brackmann (H&B) grading system, bilateral facial nerve ...

The entomopathogenic fungus Nomuraea rileyi impairs cellular immunity of its host Helicoverpa armigera.

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Zhong, Ke; Liu, Zhan-Chi; Wang, Jia-Lin; Liu, Xu-Sheng

2017-09-01

In this study, we investigated the effect of the entomopathogenic fungus Nomuraea rileyi on Helicoverpa armigera cellular immune responses. Nomuraea rileyi infection had no effect on total hemocyte count (THC), but impaired hemocyte-mediated phagocytosis, nodulation, and encapsulation responses. Nomuraea rileyi infection led to a significant reduction in hemocyte spreading. An in vitro assay revealed that plasma from N. rileyi infected H. armigera larvae suppressed the spreading ability of hemocytes from naïve larvae. We infer that N. rileyi suppresses the cellular immune response of its host, possibly by secreting exogenous, cytotoxic compounds into the host's hemolymph. © 2017 Wiley Periodicals, Inc.

Cellular and humoral immunity after vaccination or natural mumps infection.

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Terada, Kihei; Hagihara, Kimiko; Oishi, Tomohiro; Miyata, Ippei; Akaike, Hiroto; Ogita, Satoko; Ohno, Naoki; Ouchi, Kazunobu

2017-08-01

This study measured cell-mediated immunity (CMI) and serum antibody to clarify the basis of breakthrough after vaccination and reinfection after mumps. From a pool of 54 college students, 17 seronegative subjects and 14 subjects with intermediate level of antibodies against mumps were vaccinated with a monovalent mumps vaccine, and CMI was assessed using interferon-γ release assay. CMI positivity according to pre-existing antibody level, defined as titer  0.05), respectively. Vaccination or even natural mumps infection did not always induce both cellular and humoral immunity. © 2017 Japan Pediatric Society.

Effect of ceruloplasmin on some cellular and humoral immunity indices in irradiated animals

International Nuclear Information System (INIS)

Berdyins'kikh, N.K.; Savtsova, Z.D.; Yindik, V.M.

1993-01-01

The ceruloplasmin (CD) in animals being permanently under combined external and internal low-intensity ionizing irradiation is shown to increase the level of cellular immunity reactions, including antiviral ones, and of natural resistance reactions, to decrease probability of derangement of biosynthetic processes during the development of immune response, and to increase resistance of animals to influenza infection. The influence of C P on humoral antiviral immunity was not observed

Persistent Low-Level Replication of SIVΔnef Drives Maturation of Antibody and CD8 T Cell Responses to Induce Protective Immunity against Vaginal SIV Infection.

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Sama Adnan

2016-12-01

Full Text Available Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef vaccination were protected, as defined by either apparent sterile protection or significant suppression of viremia in infected animals. Multiple parameters of CD8 T cell function temporally correlated with maturation of protection, including polyfunctionality, phenotypic differentiation, and redistribution to gut and lymphoid tissues. Importantly, we also demonstrate the induction of a tissue-resident memory population of SIV-specific CD8 T cells in the vaginal mucosa, which was dependent on ongoing low-level antigenic stimulation. Moreover, we show that vaginal and serum antibody titers inversely correlated with post-challenge peak viral load, and we correlate the accumulation and affinity maturation of the antibody response to the duration of the vaccination period as well as to the SIVΔnef antigenic load. In conclusion, maturation of SIVΔnef-induced CD8 T cell and antibody responses, both propelled by viral persistence in the gut mucosa and secondary lymphoid tissues, results in protective immune responses that are able to interrupt viral transmission at mucosal portals of entry as well as potential sites of viral dissemination.

Cellular immunity and immunopathology in autoimmune Addison's disease.

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Bratland, Eirik; Husebye, Eystein S

2011-04-10

Autoimmune adrenocortical failure, or Addison's disease, is a prototypical organ-specific autoimmune disorder. In common with related autoimmune endocrinopathies, Addison's disease is only manageable to a certain extent with replacement therapy being the only treatment option. Unfortunately, the available therapy does not restore the physiological hormone levels and biorhythm. The key to progress in treating and preventing autoimmune Addison's disease lies in improving our understanding of the predisposing factors, the mechanisms responsible for the progression of the disease, and the interactions between adrenal antigens and effector cells and molecules of the immune system. The aim of the present review is to summarize the current knowledge on the role of T cells and cellular immunity in the pathogenesis of autoimmune Addison's disease. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Differential protective effects of immune lymphoid cells against transplanted line Ib leukemia and immune polioencephalomyelitis. [X radiation, mice

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Duffey, P.S.; Lukasewycz, O.A.; Olson, D.S.; Murphy, W.H.

1978-12-01

The capacity of immune cells obtained from the major lymphoid compartments to protect C58 mice from transplanted line Ib leukemia, and from an age-dependent autoimmune CNS disease (immune polioencephalomyelitis = IPE) elicited by immunizing old C58 mice with inactivated Ib cells was quantified. Cells used for comparative adoptive protection tests were harvested from the major lymphoid compartments 14 to 15 days after young C58 mice were immunized with inactivated Ib cell preparations. Regression curves were plotted from survival data and the log/sub 10/PD/sub 50/ values were determined. Immune spleen (ISC) and peritoneal cells (IPEC) were significantly more protective against transplanted Ib cells than immune lymph node (ILNC), thymic (ITC), and marrow cells (IMC). In contrast, IPEC and IMC were not protective against IPE and ITC were only marginally protective. ILNC afforded significant protection to transplantable leukemia but were only marginally protective to IPE. When ISC were treated with anti-thy 1.2 serum and complement, protection against transplanted leukemia and IPE was reduced > 99%. When donors of immune lymphoid cells were treated with 12.5 mg of cortisone acetate daily for 2 days before lymphoid cells were harvested, protection against transplanted Ib cells by ISC was reduced by approximately 90% whereas protection against IPE was totally eliminated. Considered together, these results indicate that the protective mechanisms to transplantable leukemia and IPE differ significantly in the same indicator mouse strain.

Prime immunization with rotavirus VLP 2/6 followed by boosting with an adenovirus expressing VP6 induces protective immunization against rotavirus in mice

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Qu Jianguo

2011-01-01

Full Text Available Abstract Background Rotavirus (RV is the main cause of severe gastroenteritis in children. An effective vaccination regime against RV can substantially reduce morbidity and mortality. Previous studies have demonstrated the efficacy of virus-like particles formed by RV VP2 and VP6 (VLP2/6, as well as that of recombinant adenovirus expressing RV VP6 (rAd, in eliciting protective immunities against RV. However, the efficacy of such prime-boost strategy, which incorporates VLP and rAd in inducing protective immunities against RV, has not been addressed. We assessed the immune effects of different regimens in mice, including rAd prime-VLP2/6 boost (rAd+VLP, VLP2/6 prime-rAd boost (VLP+rAd, rAd alone, and VLP alone. Results Mice immunized with the VLP+rAd regimen elicit stronger humoral, mucosal, and cellular immune responses than those immunized with other regimens. RV challenging experiments showed that the highest reduction (92.9% in viral shedding was achieved in the VLP+rAd group when compared with rAd+VLP (25%, VLP alone (75%, or rAd alone (40% treatment groups. The reduction in RV shedding in mice correlated with fecal IgG (r = 0.95773, P = 0.04227 and IgA (r = 0.96137, P = 0.038663. Conclusions A VLP2/6 prime-rAd boost regimen is effective in conferring immunoprotection against RV challenge in mice. This finding may lay the groundwork for an alternative strategy in novel RV vaccine development.

Characterization of humoral and cellular immune responses in patients with human papilloma virus

International Nuclear Information System (INIS)

Clares Pochet, Maria del Carmen; Ferrer Cosme, Belkis Maria; Dominguez Cardosa, Magda

2012-01-01

A descriptive and cross-sectional study was carried out in 30 females infected with the human papilloma virus, attended in the office of Immunology of the Specialty Polyclinic belonging to 'Saturnino Lora' Provincial Clinical Surgical Teaching Hospital in Santiago de Cuba, from June 2009 to June 2010, in order to characterize them according to immune response. To evaluate the humoral and cellular immune response rosetting assay and quantification of immunoglobulins were used respectively. Women between 25-36 years of age (40 %) infected with this virus, especially those coming from urban areas, prevailed in the series, and a significant decrease of the cellular response as compared to the humoral response was evidenced

Immunity to sporozoite-induced malaria infection in mice. I. The effect of immunization of T and B cell-deficient mice

International Nuclear Information System (INIS)

Chen, D.H.; Tigelaar, R.E.; Weinbaum, F.I.

1977-01-01

The cellular basis of immunity to sporozoites was investigated by examining the effect of immunization of T and B cell-deficient C57BL/6N x BALB/c AnN F 1 (BLCF 1 ) mice compared to immunocompetent controls. Immunization of T cell-deficient (ATX-BM-ATS) BLCF 1 mice with x-irradiated sporozoites did not result in the generation of protective immunity. The same immunization protocols protected all immunocompetent controls. In contrast, B cell-deficient (μ-suppressed) BLCF 1 mice were protected by immunization in the majority of cases. The absence of detectable serum circumsporozoite precipitins or sporozoite neutralizing activity in the μ-suppressed mice that resisted a sporozoite challenge suggests a minor role for these humoral factors in protection. These data demonstrate a preeminent role for T cells in the induction of protective immunity in BLCF 1 mice against a P. berghei sporozoite infection

Effect of partially purified fumonisins on cellular immune response in ...

African Journals Online (AJOL)

After 7 days, cellular immune response was evaluated by delayed-type hypersensitivity (DTH) and lymphoproliferative assays (LA) using spleen cells. Nitric oxide (NO) production by spleen cells was also evaluated. The specific LA response to Pb antigen was higher in group PB than in FB and CTR groups (p< 0.05) but not ...

Insect immunity shows specificity in protection upon secondary pathogen exposure.

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Sadd, Ben M; Schmid-Hempel, Paul

2006-06-20

Immunological memory in vertebrates, conferring lasting specific protection after an initial pathogen exposure, has implications for a broad spectrum of evolutionary, epidemiological, and medical phenomena . However, the existence of specificity in protection upon secondary pathogen exposure in invertebrates remains controversial . To separate this functional phenomenon from a particular mechanism, we refer to it as specific immune priming. We investigate the presence of specific immune priming in workers of the social insect Bombus terrestris. Using three bacterial pathogens, we test whether a prior homologous pathogen exposure gives a benefit in terms of long-term protection against a later challenge, over and above a heterologous combination. With a reciprocally designed initial and second-exposure protocol (i.e., all combinations of bacteria were tested), we demonstrate, even several weeks after the clearance of a first exposure, increased protection and narrow specificity upon secondary exposure. This demonstrates that the invertebrate immune system is functionally capable of unexpectedly specific and durable induced protection. Ultimately, despite general broad differences between vertebrates and invertebrates, the ability of both immune systems to show specificity in protection suggests that their immune defenses have found comparable solutions to similar selective pressures over evolutionary time.

Reduction of porcine circovirus type 2 (PCV2 viremia by a reformulated inactivated chimeric PCV1-2 vaccine-induced humoral and cellular immunity after experimental PCV2 challenge

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Seo Hwi

2012-10-01

Full Text Available Abstract Background The objective of the present study was to elucidate the humoral and cellular immune response mechanisms by which a reformulated inactivated chimeric PCV1-2 vaccine reduces the PCV2 viremia. Forty PCV2 seronegative 3-week-old pigs were randomly divided into the following four groups: vaccinated challenged (T01, vaccinated non-challenged (T02, non-vaccinated challenged (T03, and non-vaccinated non-challenged (T04 animals. The pigs in groups T01 and T02 were immunized with a reformulated inactivated chimeric PCV1-2 vaccine (Fostera™ PCV; Pfizer Animal Health administered as a 2.0 ml dose at 21 days of age. At 35 days of age (0 days post-challenge, the pigs in groups T01 and T03 were inoculated intranasally with 2 ml each of PCV2b. Results A reduction of PCV2 viremia coincided with the appearance of both PCV2-specific neutralizing antibodies (NA and interferon-γ-secreting cells (IFN-γ-SCs in the vaccinated animals. However, the presence of anti-PCV2 IgG antibodies did not correlate with the reduction of PCV2 viremia. Lymphocyte subset analysis indicated that the numbers of CD3+ and CD4+ cells increased in vaccinated animals but the numbers of CD4+ cells decreased transiently in non-vaccinated animals. The observation of a delayed type hypersensitivity response in only the vaccinated animals also supports a CD4+ cell-associated protective cellular immune response induced by the reformulated inactivated chimeric PCV1-2 vaccine. Conclusions The induction of PCV2-specific NA and IFN-γ-SCs, and CD4+ cells by the reformulated inactivated chimeric PCV1-2 vaccine is the important protective immune response leading to reduction of the PCV2 viremia and control of the PCV2 infection. To our knowledge this is the first demonstration of protective humoral and cellular immunity induced by the reformulated inactivated chimeric PCV1-2 vaccine and its effect on reduction of PCV2 viremia by vaccination.

Epitope-based vaccines with the Anaplasma marginale MSP1a functional motif induce a balanced humoral and cellular immune response in mice.

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Paula S Santos

Full Text Available Bovine anaplasmosis is a hemoparasitic disease that causes considerable economic loss to the dairy and beef industries. Cattle immunized with the Anaplasma marginale MSP1 outer membrane protein complex presents a protective humoral immune response; however, its efficacy is variable. Immunodominant epitopes seem to be a key-limiting factor for the adaptive immunity. We have successfully demonstrated that critical motifs of the MSP1a functional epitope are essential for antibody recognition of infected animal sera, but its protective immunity is yet to be tested. We have evaluated two synthetic vaccine formulations against A. marginale, using epitope-based approach in mice. Mice infection with bovine anaplasmosis was demonstrated by qPCR analysis of erythrocytes after 15-day exposure. A proof-of-concept was obtained in this murine model, in which peptides conjugated to bovine serum albumin were used for immunization in three 15-day intervals by intraperitoneal injections before challenging with live bacteria. Blood samples were analyzed for the presence of specific IgG2a and IgG1 antibodies, as well as for the rickettsemia analysis. A panel containing the cytokines' transcriptional profile for innate and adaptive immune responses was carried out through qPCR. Immunized BALB/c mice challenged with A. marginale presented stable body weight, reduced number of infected erythrocytes, and no mortality; and among control groups mortality rates ranged from 15% to 29%. Additionally, vaccines have significantly induced higher IgG2a than IgG1 response, followed by increased expression of pro-inflammatory cytokines. This is a successful demonstration of epitope-based vaccines, and protection against anaplasmosis may be associated with elicitation of effector functions of humoral and cellular immune responses in murine model.

Heterologous Protection against Malaria after Immunization with Plasmodium falciparum Sporozoites.

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Remko Schats

Full Text Available Sterile protection in >90% of volunteers against homologous Plasmodium falciparum infection has been achieved only using the controlled human malaria infection (CHMI model. This efficient model involves whole parasite immunizations under chloroquine prophylaxis (CPS-immunization, requiring only 30-45 mosquitoes bites infected with P. falciparum-sporozoites. Given the large diversity of P. falciparum parasites, it is essential to assess protection against heterologous parasite strains.In an open-label follow-up study, 16 volunteers previously CPS-immunized and challenged with P. falciparum NF54 (West-Africa in a dose de-escalation and challenge trial were re-challenged with clone NF135.C10 (Cambodia at 14 months after the last immunization (NCT01660854.Two out of thirteen NF54 protected volunteers previously fully protected against NF54 were also fully protected against NF135.C10, while 11/13 showed a delayed patency (median prepatent period of 10.5 days (range 9.0-15.5 versus 8.5 days in 5 malaria-naïve controls (p = 0.0005. Analysis of patency by qPCR indicated a 91 to >99% estimated reduction of liver parasite load in 7/11 partially protected subjects. Three volunteers previously not protected against NF54, were also not protected against NF135.C10.This study shows that CPS-immunization can induce heterologous protection for a period of more than one year, which is a further impetus for clinical development of whole parasite vaccines.Clinicaltrials.gov NCT01660854.

Indices of cellular immunity following radioiodine therapy of thyrotaxicosis

International Nuclear Information System (INIS)

Livergant, Yu.Eh.; Yakimova, T.P.; Duma, V.A.; Mikulinskij, Yu.E.

1978-01-01

Indices of cellular immunity were studied in patients with thyrotoxicosis before and after treatment with 131 J. Blast-cell transformation of lumphocytes in 154 patients with thyrotoxicosis was found to be somewhat increased, both in stimulation by phytohemagglutinin and, particularly, spontaneous, in the autologous medium without a stimulator; an elevated activity of lymphocytes correlated with the severity of the clinical course of the disease. Following the successful treatment with 131 J frequency of increase in blast-cell transformation of lumphocytes dropped. Normalization of its indices was seen also in late complication of the treatment of thyrotoxicosis 131 J with hypothyrosis. An elevated index apparently was associated with the cessation of thyrotoxicosis rather than with the radiation effect of 131 J. Addition of an extract of homologous tissue of the thyroid gland to the culture of lymphocytes did not enhance blast-cell formation. Intracutaneous test for administration of an extract of homologous tissue of the toxic goiter was positive in half of patients with thyrotoxicosis before treatment, in 22 % of patients with remission after treatment with 131 J, and also in 64% of patients with late complication of treatment with hypothyrosis. Significance of cellular immunity in the development of autoimmune agression of the thyroid gland is discussed

Pertussis Maternal Immunization: Narrowing the Knowledge Gaps on the Duration of Transferred Protective Immunity and on Vaccination Frequency

Science.gov (United States)

Gaillard, María Emilia; Bottero, Daniela; Zurita, María Eugenia; Carriquiriborde, Francisco; Martin Aispuro, Pablo; Bartel, Erika; Sabater-Martínez, David; Bravo, María Sol; Castuma, Celina; Hozbor, Daniela Flavia

2017-01-01

Maternal safety through pertussis vaccination and subsequent maternal–fetal-antibody transfer are well documented, but information on infant protection from pertussis by such antibodies and by subsequent vaccinations is scarce. Since mice are used extensively for maternal-vaccination studies, we adopted that model to narrow those gaps in our understanding of maternal pertussis immunization. Accordingly, we vaccinated female mice with commercial acellular pertussis (aP) vaccine and measured offspring protection against Bordetella pertussis challenge and specific-antibody levels with or without revaccination. Maternal immunization protected the offspring against pertussis, with that immune protection transferred to the offspring lasting for several weeks, as evidenced by a reduction (4–5 logs, p protection to offspring up to the fourth pregnancy. Under the conditions of our experimental protocol, protection to offspring from the aP-induced immunity is transferred both transplacentally and through breastfeeding. Adoptive-transfer experiments demonstrated that transferred antibodies were more responsible for the protection detected in offspring than transferred whole spleen cells. In contrast to reported findings, the protection transferred was not lost after the vaccination of infant mice with the same or other vaccine preparations, and conversely, the immunity transferred from mothers did not interfere with the protection conferred by infant vaccination with the same or different vaccines. These results indicated that aP-vaccine immunization of pregnant female mice conferred protective immunity that is transferred both transplacentally and via offspring breastfeeding without compromising the protection boostered by subsequent infant vaccination. These results—though admittedly not necessarily immediately extrapolatable to humans—nevertheless enabled us to test hypotheses under controlled conditions through detailed sampling and data collection. These

Pertussis Maternal Immunization: Narrowing the Knowledge Gaps on the Duration of Transferred Protective Immunity and on Vaccination Frequency

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María Emilia Gaillard

2017-09-01

Full Text Available Maternal safety through pertussis vaccination and subsequent maternal–fetal-antibody transfer are well documented, but information on infant protection from pertussis by such antibodies and by subsequent vaccinations is scarce. Since mice are used extensively for maternal-vaccination studies, we adopted that model to narrow those gaps in our understanding of maternal pertussis immunization. Accordingly, we vaccinated female mice with commercial acellular pertussis (aP vaccine and measured offspring protection against Bordetella pertussis challenge and specific-antibody levels with or without revaccination. Maternal immunization protected the offspring against pertussis, with that immune protection transferred to the offspring lasting for several weeks, as evidenced by a reduction (4–5 logs, p < 0.001 in the colony-forming-units recovered from the lungs of 16-week-old offspring. Moreover, maternal-vaccination-acquired immunity from the first pregnancy still conferred protection to offspring up to the fourth pregnancy. Under the conditions of our experimental protocol, protection to offspring from the aP-induced immunity is transferred both transplacentally and through breastfeeding. Adoptive-transfer experiments demonstrated that transferred antibodies were more responsible for the protection detected in offspring than transferred whole spleen cells. In contrast to reported findings, the protection transferred was not lost after the vaccination of infant mice with the same or other vaccine preparations, and conversely, the immunity transferred from mothers did not interfere with the protection conferred by infant vaccination with the same or different vaccines. These results indicated that aP-vaccine immunization of pregnant female mice conferred protective immunity that is transferred both transplacentally and via offspring breastfeeding without compromising the protection boostered by subsequent infant vaccination. These results�

Protective immune mechanisms against pre-erythrocytic forms of Plasmodium berghei depend on the target antigen

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Elke S. Bergmann-Leitner

2014-01-01

Full Text Available Pre-erythrocytic malaria vaccines are believed to either stop the injected sporozoites from reaching the liver or to direct cellular immune responses towards eliminating infected hepatocytes. The present study reveals for the first time the anatomical sites at which these immune mechanisms act against the malaria parasites. To determine the mechanisms leading to protection mediated by two previously characterized vaccines against either the circumsporozoite protein (CSP or the cell traversal protein for ookinetes and sporozoites (CelTOS, mice were immunized and subsequently challenged by subcutaneous injection of salivary gland sporozoites of luciferase-transgenic Plasmodium berghei parasites. The In Vivo Imaging System (IVIS was used to identify the anatomical site where the vaccine-induced immune response eliminates sporozoites after injection. The data demonstrate that CSP-based immunity acts at the site of infection (skin whereas CelTOS-based immunity is only partially efficient in the skin and allows reduced levels of liver infection that can be subsequently cleared. The results of this study challenge assumptions regarding CSP-mediated immune mechanisms and call into question the validity of some commonly used assays to evaluate anti-CSP immune responses. The knowledge of the mechanism and events leading to infection or immune defense will guide supportive treatment with drugs or combination therapies and thus accelerate the development of effective antimalarial strategies.

Long term protection after immunization with P. berghei sporozoites correlates with sustained IFNγ responses of hepatic CD8+ memory T cells.

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Nganou-Makamdop, Krystelle; van Gemert, Geert-Jan; Arens, Theo; Hermsen, Cornelus C; Sauerwein, Robert W

2012-01-01

Protection against P. berghei malaria can successfully be induced in mice by immunization with both radiation attenuated sporozoites (RAS) arresting early during liver stage development, or sporozoites combined with chloroquine chemoprophylaxis (CPS), resulting in complete intra-hepatic parasite development before killing of blood-stages by chloroquine takes place. We assessed the longevity of protective cellular immune responses by RAS and CPS P. berghei immunization of C57BL/6j mice. Strong effector and memory (T(EM)) CD8+ T cell responses were induced predominantly in the liver of both RAS and CPS immunized mice while CD4+ T cells with memory phenotype remained at base line levels. Compared to unprotected naïve mice, we found high sporozoite-specific IFNγ ex vivo responses that associated with induced levels of in vivo CD8+ T(EM) cells in the liver but not spleen. Long term evaluation over a period of 9 months showed a decline of malaria-specific IFNγ responses in RAS and CPS mice that significantly correlated with loss of protection (r(2) = 0.60, pmemory CD8+ T cells could be boosted by re-exposure to wild-type sporozoites. Our data show that sustainable protection against malaria associates with distinct intra-hepatic immune responses characterized by strong IFNγ producing CD8+ memory T cells.

Long term protection after immunization with P. berghei sporozoites correlates with sustained IFNγ responses of hepatic CD8+ memory T cells.

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Krystelle Nganou-Makamdop

Full Text Available Protection against P. berghei malaria can successfully be induced in mice by immunization with both radiation attenuated sporozoites (RAS arresting early during liver stage development, or sporozoites combined with chloroquine chemoprophylaxis (CPS, resulting in complete intra-hepatic parasite development before killing of blood-stages by chloroquine takes place. We assessed the longevity of protective cellular immune responses by RAS and CPS P. berghei immunization of C57BL/6j mice. Strong effector and memory (T(EM CD8+ T cell responses were induced predominantly in the liver of both RAS and CPS immunized mice while CD4+ T cells with memory phenotype remained at base line levels. Compared to unprotected naïve mice, we found high sporozoite-specific IFNγ ex vivo responses that associated with induced levels of in vivo CD8+ T(EM cells in the liver but not spleen. Long term evaluation over a period of 9 months showed a decline of malaria-specific IFNγ responses in RAS and CPS mice that significantly correlated with loss of protection (r(2 = 0.60, p<0.0001. The reducing IFNγ response by hepatic memory CD8+ T cells could be boosted by re-exposure to wild-type sporozoites. Our data show that sustainable protection against malaria associates with distinct intra-hepatic immune responses characterized by strong IFNγ producing CD8+ memory T cells.

Role of Cellular Immunity in Cow’s Milk Allergy: Pathogenesis, Tolerance Induction, and Beyond

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Juandy Jo

2014-01-01

Full Text Available Food allergy is an aberrant immune-mediated reaction against harmless food substances, such as cow’s milk proteins. Due to its very early introduction, cow’s milk allergy is one of the earliest and most common food allergies. For this reason cow’s milk allergy can be recognized as one of the first indications of an aberrant inflammatory response in early life. Classically, cow’s milk allergy, as is true for most other allergies as well, is primarily associated with abnormal humoral immune responses, that is, elevation of specific immunoglobulin E levels. There is growing evidence indicating that cellular components of both innate and adaptive immunity play significant roles during the pathogenesis of cow’s milk allergy. This is true for the initiation of the allergic phenotype (stimulation and skewing towards sensitization, development and outgrowth of the allergic disease. This review discusses findings pertaining to roles of cellular immunity in allergic inflammation, and tolerance induction against cow’s milk proteins. In addition, a possible interaction between immune mechanisms underlying cow’s milk allergy and other types of inflammation (infections and noncommunicable diseases is discussed.

Thymus: The site for Development of Cellular Immunity

Indian Academy of Sciences (India)

The immune system protects our bodies against infectionsand cancers. This review introduce readers to the thymus. – a primary lymphoid organ – which is the site of developmentand maturation of functional T lymphocytes. Progenitorstem cells arise from the bone marrow and undergo sequentialdevelopment in the thymus ...

Morphological and Cellular Features of Innate Immune Reaction in Helicobacter pylori Gastritis: A Brief Review

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Antonio Ieni

2016-01-01

Full Text Available Innate and adaptive immunity are both involved in acute and chronic inflammatory processes. The main cellular players in the innate immune system are macrophages, mast cells, dendritic cells, neutrophils, eosinophils, and natural killer (NK, which offer antigen-independent defense against infection. Helicobacter pylori (H. pylori infection presents peculiar characteristics in gastric mucosa infrequently occurring in other organs; its gastric colonization determines a causal role in both gastric carcinomas and mucosa-associated lymphoid tissue lymphoma. In contrast, an active role for Epstein-Barr virus (EBV has been identified only in 9% of gastric carcinomas. The aim of the present review is to discuss the role of cellular morphological effectors in innate immunity during H. pylori infection and gastric carcinogenesis.

Perturbation of cellular immune functions in cigarette smokers and protection by palm oil vitamin E supplementation

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Jubri Zakiah

2013-01-01

Full Text Available Abstract Background Cigarette smoke contains free radicals and an have adverse effect to the immune system. Supplementation of palm oil vitamin E (palmvitee, is known has antioxidant properties is thought to be beneficial for system immune protection against free radicals activity. The objective of the study was to determine the effect of palmvitee supplementation on immune response in smokers. Methods This study involved a group of smokers and nonsmokers who received 200 mg/day palmvitee and placebo for the control group. Blood samples were taken at 0, 12 and 24 weeks of supplementation. Plasma tocopherol and tocotrienol were determined by HPLC, lymphocyte proliferation by lymphocyte transformation test (LTT and enumeration of lymphocytes T and B cells by flow cytometry. Statistical analysis was performed by Mann–Whitney U-test for non-parametric data distribution and correlation among the variables was examined by Spearman. Results Plasma tocopherol and tocotrienol were increased in vitamin E supplemented group as compared to placebo group. Urine cotinine levels and serum α1-antitrypsin were significantly higher in smokers compared to nonsmokers. Lymphocyte proliferation induced by PHA showed an increasing trend with palmvitee supplementation in both smokers and nonsmokers. Natural killer cells were decreased; CD4+ cells and B cells were increased in smokers compared to nonsmokers but were unaffected with vitamin E supplementation except in the percentage of B cells which were increased in nonsmokers supplemented palmvitee compared to placebo. CD4+/CD8+ ratio was increased in smokers compared to nonsmokers. The high TWBC count observed in smokers correlated with the increased CD4+ and B cells. Conclusions Smoking caused alterations in certain immune parameters and palmvitee supplementation tended to cause an increase in lymphocytes transformation test but had no effect on CD3+, CD4+, CD8+, NK cells and B cells except B cells percentage

Intracellular Bacterial Infections: A Challenge for Developing Cellular Mediated Immunity Vaccines for Farmed Fish

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Hetron Mweemba Munang’andu

2018-04-01

Full Text Available Aquaculture is one of the most rapidly expanding farming systems in the world. Its rapid expansion has brought with it several pathogens infecting different fish species. As a result, there has been a corresponding expansion in vaccine development to cope with the increasing number of infectious diseases in aquaculture. The success of vaccine development for bacterial diseases in aquaculture is largely attributed to empirical vaccine designs based on inactivation of whole cell (WCI bacteria vaccines. However, an upcoming challenge in vaccine design is the increase of intracellular bacterial pathogens that are not responsive to WCI vaccines. Intracellular bacterial vaccines evoke cellular mediated immune (CMI responses that “kill” and eliminate infected cells, unlike WCI vaccines that induce humoral immune responses whose protective mechanism is neutralization of extracellular replicating pathogens by antibodies. In this synopsis, I provide an overview of the intracellular bacterial pathogens infecting different fish species in aquaculture, outlining their mechanisms of invasion, replication, and survival intracellularly based on existing data. I also bring into perspective the current state of CMI understanding in fish together with its potential application in vaccine development. Further, I highlight the immunological pitfalls that have derailed our ability to produce protective vaccines against intracellular pathogens for finfish. Overall, the synopsis put forth herein advocates for a shift in vaccine design to include CMI-based vaccines against intracellular pathogens currently adversely affecting the aquaculture industry.

Immune Protection against Lethal Fungal-Bacterial Intra-Abdominal Infections.

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Lilly, Elizabeth A; Ikeh, Melanie; Nash, Evelyn E; Fidel, Paul L; Noverr, Mairi C

2018-01-16

Polymicrobial intra-abdominal infections (IAIs) are clinically prevalent and cause significant morbidity and mortality, especially those involving fungi. Our laboratory developed a mouse model of IAI and demonstrated that intraperitoneal inoculation with Candida albicans or other virulent non- albicans Candida (NAC) species plus Staphylococcus aureus resulted in 70 to 80% mortality in 48 to 72 h due to robust local and systemic inflammation (sepsis). Surprisingly, inoculation with Candida dubliniensis or Candida glabrata with S. aureus resulted in minimal mortality, and rechallenge of these mice with lethal C. albicans / S. aureus (i.e., coninfection) resulted in >90% protection. The purpose of this study was to define requirements for C. dubliniensis / S. aureus -mediated protection and interrogate the mechanism of the protective response. Protection was conferred by C. dubliniensis alone or by killed C. dubliniensis plus live S. aureus S. aureus alone was not protective, and killed S. aureus compromised C. dubliniensis -induced protection. C. dubliniensis / S. aureus also protected against lethal challenge by NAC plus S. aureus and could protect for a long-term duration (60 days between primary challenge and C. albicans/S. aureus rechallenge). Unexpectedly, mice deficient in T and B cells (Rag-1 knockouts [KO]) survived both the initial C. dubliniensis/S. aureus challenge and the C. albicans/S. aureus rechallenge, indicating that adaptive immunity did not play a role. Similarly, mice depleted of macrophages prior to rechallenge were also protected. In contrast, protection was associated with high numbers of Gr-1 hi polymorphonuclear leukocytes (PMNLs) in peritoneal lavage fluid within 4 h of rechallenge, and in vivo depletion of Gr-1 + cells prior to rechallenge abrogated protection. These results suggest that Candida species can induce protection against a lethal C. albicans / S. aureus IAI that is mediated by PMNLs and postulated to be a unique form of

CELLULAR IMMUNITY OF THE PATIENTS SUFFERING FROM RECURRENT GENITAL CANDIDOSE

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Nataša Miladinovic

2000-03-01

Full Text Available The examination of the cellular immunity parameters comprised 20 women suffering from the recurrent genital candidose (RGK in the remission phase as well as 20 women of the control grooup that never had any verified genital mucous infection. The aim of the research was to determine the interferon-gamma (INF gamma production in the culture of specifically (by the Candida albicans - HKB-antigens and non-specifically (Concavalin-A-ConA stimulated mononuclear cells of the peripheral blood of the women with the RKG as well as of the healthy women for the sake of determining a possible presence of the system cellular immunity hypo-activity. The IFN gamma was determined by the quantitative immuno-enzymic Quantikine method (R/D system, Minneapolis, USA.The IFN gamma was confirmed in minimal quantities in the cultures of the lymphocytes stimulated by the specific antigen (average value - 15 pg/ml. A considerably higher value of the produced IFN gamma was confirmed in the cultures of the stimulated lymphocytes (average value - 954 pg/ml as well as at the ConA and the HKB lymphocyte stimulus (average value - 1247 pg/ml.

Protective immunity and safety of a genetically modified influenza virus vaccine.

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Rafael Polidoro Alves Barbosa

Full Text Available Recombinant influenza viruses are promising viral platforms to be used as antigen delivery vectors. To this aim, one of the most promising approaches consists of generating recombinant viruses harboring partially truncated neuraminidase (NA segments. To date, all studies have pointed to safety and usefulness of this viral platform. However, some aspects of the inflammatory and immune responses triggered by those recombinant viruses and their safety to immunocompromised hosts remained to be elucidated. In the present study, we generated a recombinant influenza virus harboring a truncated NA segment (vNA-Δ and evaluated the innate and inflammatory responses and the safety of this recombinant virus in wild type or knock-out (KO mice with impaired innate (Myd88 -/- or acquired (RAG -/- immune responses. Infection using truncated neuraminidase influenza virus was harmless regarding lung and systemic inflammatory response in wild type mice and was highly attenuated in KO mice. We also demonstrated that vNA-Δ infection does not induce unbalanced cytokine production that strongly contributes to lung damage in infected mice. In addition, the recombinant influenza virus was able to trigger both local and systemic virus-specific humoral and CD8+ T cellular immune responses which protected immunized mice against the challenge with a lethal dose of homologous A/PR8/34 influenza virus. Taken together, our findings suggest and reinforce the safety of using NA deleted influenza viruses as antigen delivery vectors against human or veterinary pathogens.

Immunization with Tc52 or its amino terminal domain adjuvanted with c-di-AMP induces Th17+Th1 specific immune responses and confers protection against Trypanosoma cruzi.

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Marina N Matos

2017-02-01

Full Text Available The development of new adjuvants enables fine modulation of the elicited immune responses. Ideally, the use of one or more adjuvants should result in the induction of a protective immune response against the specific pathogen. We have evaluated the immune response and protection against Trypanosoma cruzi infection in mice vaccinated with recombinant Tc52 or its N- and C-terminal domains (NTc52 and CTc52 adjuvanted either with the STING (Stimulator of Interferon Genes agonist cyclic di-AMP (c-di-AMP, a pegylated derivative of α-galactosylceramide (αGC-PEG, or oligodeoxynucleotides containing unmethylated CpG motifs (ODN-CpG. All groups immunized with the recombinant proteins plus adjuvant: Tc52+c-di-AMP, NTc52+c-di-AMP, CTc52+c-di-AMP, NTc52+c-di-AMP+αGC-PEG, NTc52+CpG, developed significantly higher anti-Tc52 IgG titers than controls. Groups immunized with c-di-AMP and Tc52, NTc52 or CTc52 showed the highest Tc52-specific IgA titers in nasal lavages. All groups immunized with the recombinant proteins plus adjuvant developed a strong specific cellular immune response in splenocytes and lymph node cells with significant differences for groups immunized with c-di-AMP and Tc52, NTc52 or CTc52. These groups also showed high levels of Tc52-specific IL-17 and IFN-γ producing cells, while NTc52+CpG group only showed significant difference with control in IFN-γ producing cells. Groups immunized with c-di-AMP and Tc52, NTc52 or CTc52 developed predominantly a Th17 and Th1immune response, whereas for NTc52+CpG it was a dominant Th1 response. It was previously described that αGC-PEG inhibits Th17 differentiation by activating NKT cells. Thus, in this work we have also included a group immunized with both adjuvants (NTc52+c-di-AMP+αGC-PEG with the aim to modulate the Th17 response induced by c-di-AMP. This group showed a significant reduction in the number of Tc52-specific IL-17 producing splenocytes, as compared to the group NTc52+c-di-AMP, which has

Cytomegalovirus in the Neonate: Immune Correlates of Infection and Protection

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Mark R. Schleiss

2013-01-01

Full Text Available Fetal and neonatal infections caused by human cytomegalovirus (CMV are important causes of morbidity and occasional mortality. Development of a vaccine against congenital CMV infection is a major public health priority. Vaccine design is currently focused on strategies that aim to elicit neutralizing antibody and T-cell responses, toward the goal of preventing primary or recurrent infection in women of child-bearing age. However, there has been relatively little attention given to understanding the mechanisms of immune protection against acquisition of CMV infection in the fetus and newborn and how this information might be exploited for vaccine design. There has similarly been an insufficient study of what deficits in the immune response to CMV, both for mother and fetus, may increase susceptibility to congenital infection and disease. Protection of the fetus against vertical transmission can likely be achieved by protection of the placenta, which has its own unique immunological milieu, further complicating the analysis of the correlates of protective immunity. In this review, the current state of knowledge about immune effectors of protection against CMV in the maternal, placental, and fetal compartments is reviewed. A better understanding of immune responses that prevent and/or predispose to infection will help in the development of novel vaccine strategies.

Cytomegalovirus in the Neonate: Immune Correlates of Infection and Protection

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Schleiss, Mark R.

2013-01-01

Fetal and neonatal infections caused by human cytomegalovirus (CMV) are important causes of morbidity and occasional mortality. Development of a vaccine against congenital CMV infection is a major public health priority. Vaccine design is currently focused on strategies that aim to elicit neutralizing antibody and T-cell responses, toward the goal of preventing primary or recurrent infection in women of child-bearing age. However, there has been relatively little attention given to understanding the mechanisms of immune protection against acquisition of CMV infection in the fetus and newborn and how this information might be exploited for vaccine design. There has similarly been an insufficient study of what deficits in the immune response to CMV, both for mother and fetus, may increase susceptibility to congenital infection and disease. Protection of the fetus against vertical transmission can likely be achieved by protection of the placenta, which has its own unique immunological milieu, further complicating the analysis of the correlates of protective immunity. In this review, the current state of knowledge about immune effectors of protection against CMV in the maternal, placental, and fetal compartments is reviewed. A better understanding of immune responses that prevent and/or predispose to infection will help in the development of novel vaccine strategies. PMID:24023565

Trade-off between cellular immunity and life span in mealworm beetles Tenebrio molitor

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Indrikis KRAMS, Janīna DAUKŠTE, Inese KIVLENIECE, Ants KAASIK, Tatjana KRAMA, Todd M. REEBERG, Markus J. RANTALA

2013-06-01

Full Text Available Encapsulation is a nonspecific, cellular response through which insects defend themselves against multicellular pathogens. During this immune reaction, haemocytes recognize an object as foreign and cause other haemocytes to aggregate and form a capsule around the object, often consisting of melanized cells. The process of melanisation is accompanied by the formation of potentially toxic reactive oxygen species, which can kill not only pathogens but also host cells. In this study we tested whether the encapsulation response is costly in mealworm beetles Tenebrio molitor. We found a negative relationship between the duration of implantation via a nylon monofilament and remaining life span. We also found a negative relationship between the strength of immune response and remaining life span, suggesting that cellular immunity is costly in T. molitor, and that there is a trade-off between immune response and remaining life span. However, this relationship disappeared at 31-32 hours of implantation at 25 ± 2℃. As the disappearance of a relationship between duration of implantation and lifespan coincided with the highest values of encapsulation response, we concluded that the beetles stopped investment in the production of melanotic cells, as the implant, a synthetic parasite, was fully isolated from the host’s tissues [Current Zoology 59 (3: 340–346, 2013].

Induction of long-term protective immune responses by influenza H5N1 virus-like particles.

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Sang-Moo Kang

Full Text Available Recurrent outbreaks of highly pathogenic H5N1 avian influenza virus pose a threat of eventually causing a pandemic. Early vaccination of the population would be the single most effective measure for the control of an emerging influenza pandemic.Influenza virus-like particles (VLPs produced in insect cell-culture substrates do not depend on the availability of fertile eggs for vaccine manufacturing. We produced VLPs containing influenza A/Viet Nam1203/04 (H5N1 hemagglutinin, neuraminidase, and matrix proteins, and investigated their preclinical immunogenicity and protective efficacy. Mice immunized intranasally with H5N1 VLPs developed high levels of H5N1 specific antibodies and were 100% protected against a high dose of homologous H5N1 virus infection at 30 weeks after immunization. Protection is likely to be correlated with humoral and cellular immunologic memory at systemic and mucosal sites as evidenced by rapid anamnestic responses to re-stimulation with viral antigen in vivo and in vitro.These results provide support for clinical evaluation of H5N1 VLP vaccination as a public health intervention to mitigate a possible pandemic of H5N1 influenza.

Toxicity of cadmium in Japanese quail: Evaluation of body weight, hepatic and renal function, and cellular immune response

International Nuclear Information System (INIS)

Sant'Ana, M.G.; Moraes, R.; Bernardi, M.M.

2005-01-01

Cadmium (Cd) is an environmental pollutant that is able to alter the immune function. Previous studies have shown that, in mammals, chronic exposure to Cd decreases the release of macrophagic cytokines such as IL1 and TNα and decreases phagocytosis activity. On the other hand contradictory results showed an increase in the humoral response. The cellular response could be decreased by exposure to Cd. These alterations were observed in mammals. The present study aimed to investigate some of the toxic effects of Cd exposure in birds. In particular, the main objective of this work was to elucidate the effects of exposure to this pollutant on the cellular immune function of the Japanese quail as a model for the study of toxicity in animals exposed in nature. The animals were exposed to the metal (100 ppm, per os) during development, i.e., from 1 to 28 days old. Body weight, biochemical parameters, and cellular immune response were measured during and at the end of treatment. The results showed that the exposure to Cd for 28 days significantly reduced the body weight and induced hepatic toxicity. The kidney function and cellular immune response were not affected by the Cd exposure

Establishing a small animal model for evaluating protective immunity against mumps virus.

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Adrian Pickar

Full Text Available Although mumps vaccines have been used for several decades, protective immune correlates have not been defined. Recently, mumps outbreaks have occurred in vaccinated populations. To better understand the causes of the outbreaks and to develop means to control outbreaks in mumps vaccine immunized populations, defining protective immune correlates will be critical. Unfortunately, no small animal model for assessing mumps immunity exists. In this study, we evaluated use of type I interferon (IFN alpha/beta receptor knockout mice (IFN-α/βR-/- for such a model. We found these mice to be susceptible to mumps virus administered intranasally and intracranially. Passive transfer of purified IgG from immunized mice protected naïve mice from mumps virus infection, confirming the role of antibody in protection and demonstrating the potential for this model to evaluate mumps immunity.

Immunization with Brugia malayi Myosin as Heterologous DNA Prime Protein Boost Induces Protective Immunity against B. malayi Infection in Mastomys coucha.

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Jyoti Gupta

Full Text Available The current control strategies employing chemotherapy with diethylcarbamazine, ivermectin and albendazole have reduced transmission in some filaria-endemic areas, there is growing interest for complementary approaches, such as vaccines especially in light of threat of parasite developing resistance to mainstay drugs. We earlier demonstrated recombinant heavy chain myosin of B. malayi (Bm-Myo as a potent vaccine candidate whose efficacy was enhanced by heterologous DNA prime/protein boost (Myo-pcD+Bm-Myo vaccination in BALB/c mice. BALB/c mouse though does not support the full developmental cycle of B. malayi, however, the degree of protection may be studied in terms of transformation of challenged infective larvae (L3 to next stage (L4 with an ease of delineating the generated immunological response of host. In the current investigation, DNA vaccination with Bm-Myo was therefore undertaken in susceptible rodent host, Mastomys coucha (M. coucha which sustains the challenged L3 and facilitates their further development to sexually mature adult parasites with patent microfilaraemia. Immunization schedule consisted of Myo-pcD and Myo-pcD+Bm-Myo followed by B. malayi L3 challenge and the degree of protection was evaluated by observing microfilaraemia as well as adult worm establishment. Myo-pcD+Bm-Myo immunized animals not only developed 78.5% reduced blood microfilarial density but also decreased adult worm establishment by 75.3%. In addition, 75.4% of the recovered live females revealed sterilization over those of respective control animals. Myo-pcD+Bm-Myo triggered higher production of specific IgG and its isotypes which induced marked cellular adhesion and cytotoxicity (ADCC to microfilariae (mf and L3 in vitro. Both Th1 and Th2 cytokines were significantly up-regulated displaying a mixed immune response conferring considerable protection against B. malayi establishment by engendering a long-lasting effective immune response and therefore emerges

Effect of liniment levamisole on cellular immune functions of patients with chronic hepatitis B.

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Wang, Ke-Xia; Zhang, Li-Hua; Peng, Jiang-Long; Liang, Yong; Wang, Xue-Feng; Zhi, Hui; Wang, Xiang-Xia; Geng, Huan-Xiong

2005-12-07

To explore the effects of liniment levamisole on cellular immune functions of patients with chronic hepatitis B. The levels of T lymphocyte subsets and mIL-2R in peripheral blood mononuclear cells (PBMCs) were measured by biotin-streptavidin (BSA) technique in patients with chronic hepatitis B before and after the treatment with liniment levamisole. After one course of treatment with liniment levamisole, the levels of CD3(+), CD4(+), and the ratio of CD4(+)/CD8(+) increased as compared to those before the treatment but the level of CD8(+) decreased. The total expression level of mIL-2R in PBMCs increased before and after the treatment with liniment levamisole. Liniment levamisole may reinforce cellular immune functions of patients with chronic hepatitis B.

Effectiveness analyses may underestimate protection of infants after group C meningococcal immunization.

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Vu, David M; Kelly, Dominic; Heath, Paul T; McCarthy, Noel D; Pollard, Andrew J; Granoff, Dan M

2006-07-15

Group C meningococcal conjugate-vaccine effectiveness in the United Kingdom declines from ~90% in the first year to 0% between 1 and 4 years after immunization in infants immunized at 2, 3, and 4 months of age and to 61% in toddlers given a single dose. Confidence intervals are wide, and the extent of protection is uncertain. Serum samples were obtained from children 3-5 years of age who were participants in a preschool booster-vaccine trial. Serum bactericidal activity was measured with human complement. Group C anticapsular antibody concentrations were measured by a radioantigen binding assay. Passive protection was analyzed in an infant rat bacteremia model. Serum samples from UK children who had been immunized 2-3 years earlier as infants or toddlers had higher levels of radioantigen binding, bactericidal activity, and passive protection than did historical control serum samples from unimmunized children (P or =1 : 4 (considered to be protective) than those immunized as toddlers (61% vs. 24%; Pprotection (50% and 41%, respectively; P=.4). We found no evidence of lower immunity in children immunized as infants than as toddlers. On the basis of serum bactericidal activity and/or passive protection, 40%-50% of both age groups are protected at 2-3 years after immunization, which was significantly greater than in unimmunized historical controls (<5%).

Trachoma: protective and pathogenic ocular immune responses to Chlamydia trachomatis.

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Victor H Hu

Full Text Available Trachoma, caused by Chlamydia trachomatis (Ct, is the leading infectious blinding disease worldwide. Chronic conjunctival inflammation develops in childhood and leads to eyelid scarring and blindness in adulthood. The immune response to Ct provides only partial protection against re-infection, which can be frequent. Moreover, the immune response is central to the development of scarring pathology, leading to loss of vision. Here we review the current literature on both protective and pathological immune responses in trachoma. The resolution of Ct infection in animal models is IFNγ-dependent, involving Th1 cells, but whether this is the case in human ocular infection still needs to be confirmed. An increasing number of studies indicate that innate immune responses arising from the epithelium and other innate immune cells, along with changes in matrix metalloproteinase activity, are important in the development of tissue damage and scarring. Current trachoma control measures, which are centred on repeated mass antibiotic treatment of populations, are logistically challenging and have the potential to drive antimicrobial resistance. A trachoma vaccine would offer significant advantages. However, limited understanding of the mechanisms of both protective immunity and immunopathology to Ct remain barriers to vaccine development.

Vaccination with Recombinant Baculovirus Expressing Ranavirus Major Capsid Protein Induces Protective Immunity in Chinese Giant Salamander, Andrias davidianus

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Xiaoyuan Zhou

2017-07-01

Full Text Available The Chinese giant salamander iridovirus (CGSIV, belonging to the genus Ranavirus in the family Iridoviridae, is the causative agent of an emerging infectious disease causing high mortality of more than 90% and economic losses in Chinese giant salamanders in China. In this study, a recombinant baculovirus-based vaccine expressing the CGSIV major capsid protein (MCP was developed and its protective immunity in Chinese giant salamanders was evaluated. The recombinant Autographa californica nucleopolyhedrosis virus (AcNPV, expressing CGSIV MCP, designated as AcNPV-MCP, was generated with the highest titers of 1 × 108 plaque forming units/mL (PFU/mL and confirmed by Western blot and indirect immunofluorescence (IIF assays. Western blot analysis revealed that the expressed MCP reacted with mouse anti-MCP monoclonal antibodies at the band of about 53 kDa. The results of IIF indicated that the MCP was expressed in the infected Spodoptera frugiperda 9 (Sf9 cells with the recombinant baculovirus, and the Chinese giant salamander muscle cells also transduced with the AcNPV-MCP. Immunization with the recombinant baculovirus of AcNPV-MCP elicited robust specific humoral immune responses detected by ELISA and neutralization assays and potent cellular immune responses in Chinese giant salamanders. Importantly, the effective immunization conferred highly protective immunity for Chinese giant salamanders against CGSIV challenge and produced a relative percent of survival rate of 84%. Thus, the recombinant baculovirus expressing CGSIV MCP can induce significant immune responses involving both humoral and cell-mediated immunity in Chinese giant salamanders and might represent a potential baculovirus based vaccine candidate for Chinese giant salamanders against CGSIV.

Recombinant Forms of Leishmania amazonensis Excreted/Secreted Promastigote Surface Antigen (PSA Induce Protective Immune Responses in Dogs.

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Elodie Petitdidier

2016-05-01

Full Text Available Preventive vaccination is a highly promising strategy for interrupting leishmaniasis transmission that can, additionally, contribute to elimination. A vaccine formulation based on naturally excreted secreted (ES antigens was prepared from L. infantum promastigote culture supernatant. This vaccine achieved successful results in Phase III trials and was licensed and marketed as CaniLeish. We recently showed that newly identified ES promastigote surface antigen (PSA, from both viable promastigotes and axenically-grown amastigotes, represented the major constituent and the highly immunogenic antigen of L. infantum and L. amazonensis ES products. We report here that three immunizations with either the recombinant ES LaPSA-38S (rPSA or its carboxy terminal part LaPSA-12S (Cter-rPSA, combined with QA-21 as adjuvant, confer high levels of protection in naive L. infantum-infected Beagle dogs, as checked by bone marrow parasite absence in respectively 78.8% and 80% of vaccinated dogs at 6 months post-challenge. The parasite burden in infected vaccinated dogs was significantly reduced compared to placebo group, as measured by q-PCR. Moreover, our results reveal humoral and cellular immune response clear-cut differences between vaccinated and control dogs. An early increase in specific IgG2 antibodies was observed in rPSA/QA-21- and Cter-rPSA/QA-21-immunized dogs only. They were found functionally active in vitro and were highly correlated with vaccine protection. In vaccinated protected dogs, IFN-γ and NO productions, as well as anti-leishmanial macrophage activity, were increased. These data strongly suggest that ES PSA or its carboxy-terminal part, in recombinant forms, induce protection in a canine model of zoonotic visceral leishmaniasis by inducing a Th1-dominant immune response and an appropriate specific antibody response. These data suggest that they could be considered as important active components in vaccine candidates.

Discovering naturally processed antigenic determinants that confer protective T cell immunity

DEFF Research Database (Denmark)

Gilchuk, Pavlo; Spencer, Charles T; Conant, Stephanie B

2013-01-01

and elicited protective TCD8 immunity against lethal intranasal VACV infection. Notably, efficient processing and stable presentation of immune determinants as well as the availability of naive TCD8 precursors were sufficient to drive a multifunctional, protective TCD8 response. Our approach uses fundamental...

HIV-specific humoral and cellular immunity in rabbits vaccinated with recombinant human immunodeficiency virus-like gag-env particles

International Nuclear Information System (INIS)

Haffar, O.K.; Smithgall, M.D.; Moran, P.A.; Travis, B.M.; Zarling, J.M.; Hu, S.L.

1991-01-01

Recombinant human immunodeficiency virus type-1 (HIV-1)-like gag-env particles produced in mammalian cells were inoculated into two New Zealand white rabbits. In parallel, two control rabbits were inoculated with the homologous HIV-1 virions inactivated by ultraviolet light (uv) and psoralen treatments. The humoral and cellular immune responses to HIV-1 were evaluated for both groups of animals. Recombinant particles elicited humoral immunity that was specific for all the viral structural proteins. The antibodies recognized both denatured and nondenatured proteins. Moreover, the sera neutralized the in vitro infectivity of the homologous virus in CEM cells. Importantly, the recombinant particles also generated a T helper response by priming with the HIV proteins. Similar results were observed with inactivated virus immunization. Therefore, the authors results suggest that the recombinant HIV-like particles elicit functional humoral immunity as well as cellular immunity and represent a novel vaccine candidate for AIDS

Evaluation of the protection induced by the immunization with radioiodinated yeast cells of Paracoccidioides brasiliensis in animal model

International Nuclear Information System (INIS)

Martins, Estefania Mara do Nascimento

2007-01-01

stimulation of the cellular response. The protection assay performed with mice immunized once showed a significant reduction in the CFU's recovery evaluated 30 days after the challenge. However, when examined 90 days after the challenge the CFU's recovered from organs increased. Even so a significant degree of protection has been reached these results point that only one immunization was not enough to confer a long lasting protection, since some focus of the fungi were not eliminated. An efficient protection against highly infective forms of P. brasiliensis was developed in the mice group immunized twice. The immunization was able to reduce the initial infection and elicited a long lasting protection. A 99,5 % protection was obtained in the mice analyzed 90 days post challenge. At the same time the levels of IFN - γ and TNF - α increased significantly while the IL-10 and IL - 5 decreased. When analyzed after 30 days, the mice had not developed a totally polarized pattern of Th1/Th2 response but, a trend to a Th1 response was evident after 90 days. The level of IgG increased in both immunized groups after the challenge. We concluded that the immunization with the radio attenuated yeast cells was able to elicit a long lasting protective immune response and these cells are valuable tool for protective immunity studies and vaccine research for PCM. (author)

Exposure to low infective doses of HCV induces cellular immune responses without consistently detectable viremia or seroconversion in chimpanzees

International Nuclear Information System (INIS)

Shata, Mohamed Tarek; Tricoche, Nancy; Perkus, Marion; Tom, Darley; Brotman, Betsy; McCormack, Patricia; Pfahler, Wolfram; Lee, Dong-Hun; Tobler, Leslie H.; Busch, Michael; Prince, Alfred M.

2003-01-01

In hepatitis C virus (HCV) infection, there is accumulating data suggesting the presence of cellular immune responses to HCV in exposed but seemingly uninfected populations. Some studies have suggested cross-reactive antigens rather than prior HCV exposure as the main reason for the immune responses. In this study we address this question by analyzing the immune response of chimpanzees that have been sequentially exposed to increasing doses of HCV virions. The level of viremia, as well as the immune responses to HCV at different times after virus inoculation, were examined. Our data indicate that HCV infective doses as low as 1-10 RNA (+) virions induce detectable cellular immune responses in chimpanzees without consistently detectable viremia or persistent seroconversion. However, increasing the infective doses of HCV to 100 RNA (+) virions overcame the low-inoculum-induced immune response and produced high-level viremia followed by seroconversion

Inactivated Influenza Vaccine That Provides Rapid, Innate-Immune-System-Mediated Protection and Subsequent Long-Term Adaptive Immunity.

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Chua, Brendon Y; Wong, Chinn Yi; Mifsud, Edin J; Edenborough, Kathryn M; Sekiya, Toshiki; Tan, Amabel C L; Mercuri, Francesca; Rockman, Steve; Chen, Weisan; Turner, Stephen J; Doherty, Peter C; Kelso, Anne; Brown, Lorena E; Jackson, David C

2015-10-27

The continual threat to global health posed by influenza has led to increased efforts to improve the effectiveness of influenza vaccines for use in epidemics and pandemics. We show in this study that formulation of a low dose of inactivated detergent-split influenza vaccine with a Toll-like receptor 2 (TLR2) agonist-based lipopeptide adjuvant (R4Pam2Cys) provides (i) immediate, antigen-independent immunity mediated by the innate immune system and (ii) significant enhancement of antigen-dependent immunity which exhibits an increased breadth of effector function. Intranasal administration of mice with vaccine formulated with R4Pam2Cys but not vaccine alone provides protection against both homologous and serologically distinct (heterologous) viral strains within a day of administration. Vaccination in the presence of R4Pam2Cys subsequently also induces high levels of systemic IgM, IgG1, and IgG2b antibodies and pulmonary IgA antibodies that inhibit hemagglutination (HA) and neuraminidase (NA) activities of homologous but not heterologous virus. Improved primary virus nucleoprotein (NP)-specific CD8(+) T cell responses are also induced by the use of R4Pam2Cys and are associated with robust recall responses to provide heterologous protection. These protective effects are demonstrated in wild-type and antibody-deficient animals but not in those depleted of CD8(+) T cells. Using a contact-dependent virus transmission model, we also found that heterologous virus transmission from vaccinated mice to naive mice is significantly reduced. These results demonstrate the potential of adding a TLR2 agonist to an existing seasonal influenza vaccine to improve its utility by inducing immediate short-term nonspecific antiviral protection and also antigen-specific responses to provide homologous and heterologous immunity. The innate and adaptive immune systems differ in mechanisms, specificities, and times at which they take effect. The innate immune system responds within hours of

Host immunity in the protective response to nasal immunization with a pneumococcal antigen associated to live and heat-killed Lactobacillus casei.

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Vintiñi, Elisa O; Medina, Marcela S

2011-08-11

At present, available pneumococcal vaccines have failed to eradicate infections caused by S. pneumoniae. Search for effective vaccine continues and some serotype independent pneumococcal proteins are considered as candidates for the design of new vaccines, especially a mucosal vaccine, since pneumococci enter the body through mucosal surfaces. Selection of the appropriate adjuvant is important for mucosal vaccines, and lactic acid bacteria (LAB) with immunostimulant properties are promissory candidates. In this work, we assessed the adjuvant effect of a probiotic strain, Lactobacillus casei (L. casei), when nasally administered with a pneumococcal antigen (pneumococcal protective protein A: PppA) for the prevention of pneumococcal infection. Adjuvanticity of both live (LcV) and heat-killed (LcM) was evaluated and humoral and cellular antigen-specific immune response was assessed in mucosal and systemic compartments. The potential mechanisms induced by nasal immunization were discussed. Nasal immunization of young mice with PppA+LcV and PppA+LcM induced anti-PppA IgA and IgG antibodies in mucosal and systemic compartments and levels of these specific antibodies remained high even at day 45 after the 3rd Immunization (3rd I). These results were correlated with IL-4 induction by the mixture of antigen plus LcV and LcM. Also, PppA+Lc (V and M) induced stimulation of Th1 and Th17 cells involved in the defence against pneumococci. The protection against pneumococcal respiratory challenge at day 30 after the 3rd I showed that PppA+LcV and PppA+LcM immunizations significantly reduced pathogen counts in nasal lavages while prventing their passage into lung and blood. Survival of mice immunized with the co-application of PppA plus LcV and LcM was significantly higher than in mice immunized with PppA alone and control mice when intraperitoneal challenge was performed. No significant differences between the treatments involving LcV and LcM were found. Live and heat-killed L

Host immunity in the protective response to nasal immunization with a pneumococcal antigen associated to live and heat-killed Lactobacillus casei

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Vintiñi Elisa O

2011-08-01

Full Text Available Abstract Background At present, available pneumococcal vaccines have failed to eradicate infections caused by S. pneumoniae. Search for effective vaccine continues and some serotype independent pneumococcal proteins are considered as candidates for the design of new vaccines, especially a mucosal vaccine, since pneumococci enter the body through mucosal surfaces. Selection of the appropriate adjuvant is important for mucosal vaccines, and lactic acid bacteria (LAB with immunostimulant properties are promissory candidates. In this work, we assessed the adjuvant effect of a probiotic strain, Lactobacillus casei (L. casei, when nasally administered with a pneumococcal antigen (pneumococcal protective protein A: PppA for the prevention of pneumococcal infection. Adjuvanticity of both live (LcV and heat-killed (LcM was evaluated and humoral and cellular antigen-specific immune response was assessed in mucosal and systemic compartments. The potential mechanisms induced by nasal immunization were discussed. Results Nasal immunization of young mice with PppA+LcV and PppA+LcM induced anti-PppA IgA and IgG antibodies in mucosal and systemic compartments and levels of these specific antibodies remained high even at day 45 after the 3rd Immunization (3rd I. These results were correlated with IL-4 induction by the mixture of antigen plus LcV and LcM. Also, PppA+Lc (V and M induced stimulation of Th1 and Th17 cells involved in the defence against pneumococci. The protection against pneumococcal respiratory challenge at day 30 after the 3rd I showed that PppA+LcV and PppA+LcM immunizations significantly reduced pathogen counts in nasal lavages while prventing their passage into lung and blood. Survival of mice immunized with the co-application of PppA plus LcV and LcM was significantly higher than in mice immunized with PppA alone and control mice when intraperitoneal challenge was performed. No significant differences between the treatments involving LcV and

Circumsporozoite Protein-Specific Kd-Restricted CD8+ T Cells Mediate Protective Antimalaria Immunity in Sporozoite-Immunized MHC-I-Kd Transgenic Mice

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Jing Huang

2014-01-01

Full Text Available Although the roles of CD8+ T cells and a major preerythrocytic antigen, the circumsporozoite (CS protein, in contributing protective antimalaria immunity induced by radiation-attenuated sporozoites, have been shown by a number of studies, the extent to which these players contribute to antimalaria immunity is still unknown. To address this question, we have generated C57BL/6 (B6 transgenic (Tg mice, expressing Kd molecules under the MHC-I promoter, called MHC-I-Kd-Tg mice. In this study, we first determined that a single immunizing dose of IrPySpz induced a significant level of antimalaria protective immunity in MHC-I-Kd-Tg mice but not in B6 mice. Then, by depleting various T-cell subsets in vivo, we determined that CD8+ T cells are the main mediator of the protective immunity induced by IrPySpz. Furthermore, when we immunized (MHC-I-Kd-Tg × CS-Tg F1 mice with IrPySpz after crossing MHC-I-Kd-Tg mice with PyCS-transgenic mice (CS-Tg, which are unable to mount PyCS-specific immunity, we found that IrPySpz immunization failed to induce protective antimalaria immunity in (MHC-I-Kd-Tg × CS-Tg F1 mice, thus indicating the absence of PyCS antigen-dependent immunity in these mice. These results indicate that protective antimalaria immunity induced by IrPySpz in MHC-I-Kd-Tg mice is mediated by CS protein-specific, Kd-restricted CD8+ T cells.

Influence of Some Pesticides on Humoral and Cellular Immunity of Exposed Workers in Pesticides Industries

International Nuclear Information System (INIS)

Osely, E.Sh.M.

2010-01-01

Pesticide poisoning is a major public health problem in developing countries. In most of these countries organophosphate pesticides constitute the most widely used pesticides. The main toxicity of OPs is neurotoxicity, which is caused by the inhibition of acetylcholinesterase. OPs also affect the immune response, including effects on cellular and humoral immunity. Our study examined the effect of organophosphorus compounds on humoral and cellular immunity of exposed workers in pesticides industries. The study was conducted into 40 subjects. They were 2 groups; 20 exposed workers from Gharbeia and Kafr Elsheikh at 2008 and 2009 and 20 unexposed individuals as a control group at the same period of time. We examined some immune parameters; pseudocholinesterase, WBCs count, CD4%, CD8%, CD4/CD8, CD56%, Interleukin 2, IgG and IgM. Also we take history and clinical examination for them. We reported a highly significant decrease in pseudo cholinesterase level among the exposed group in comparison to the control group, highly significant increase in percentage of CD8 in the exposed group in comparison to control group, highly significant decrease in CD4 / CD8 ratio in the exposed group in comparison to control group, highly significant decrease in percentage of CD56 in the exposed group in comparison to control group and a highly significant increase in IgG level in the exposed group in comparison to control group. On the other hand, we reported no significant change in white blood cells count between the exposed and control groups, no significant change in percentage of CD4 among the exposed and control group, no significant change in Interleukin 2 level among the exposed and control group and no significant change in IgM level among the exposed and control group. We concluded that pesticides extensively affect the humoral and cellular immune system of occupationally exposed workers.

Cellular immune responses to HPV-18, -31, and -53 in healthy volunteers immunized with recombinant HPV-16 L1 virus-like particles

International Nuclear Information System (INIS)

Pinto, Ligia A.; Viscidi, Raphael; Harro, Clayton D.; Kemp, Troy J.; Garcia-Pineres, Alfonso J.; Trivett, Matthew; Demuth, Franklin; Lowy, Douglas R.; Schiller, John T.; Berzofsky, Jay A.; Hildesheim, Allan

2006-01-01

Human papillomavirus-like particles (HPV VLP) are candidate vaccines that have shown to be efficacious in reducing infection and inducing robust antiviral immunity. Neutralizing antibodies generated by vaccination are largely type-specific, but little is known about the type-specificity of cellular immune responses to VLP vaccination. To determine whether vaccination with HPV-16 L1VLP induces cellular immunity to heterologous HPV types (HPV-18, HPV-31, and HPV-53), we examined proliferative and cytokine responses in vaccine (n = 11) and placebo (n = 5) recipients. Increased proliferative and cytokine responses to heterologous types were observed postvaccination in some individuals. The proportion of women responding to heterologous types postvaccination (36%-55%) was lower than that observed in response to HPV-16 (73%). Response to HPV-16 VLP predicted response to other types. The strongest correlations in response were observed between HPV-16 and HPV-31, consistent with their phylogenetic relatedness. In summary, PBMC from HPV-16 VLP vaccine recipients can respond to L1VLP from heterologous HPV types, suggesting the presence of conserved T cell epitopes

The immune response to sand fly salivary proteins and its influence on Leishmania immunity

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Regis eGomes

2012-05-01

Full Text Available Leishmaniasis is a vector-borne disease transmitted by bites of phlebotomine sand flies. During Leishmania transmission, sand fly saliva is co-inoculated with parasites into the skin of the mammalian host. Sand fly saliva consists of roughly thirty different salivary proteins, many with known roles linked to blood feeding facilitation. Apart from the anti-hemostatic capacity of saliva, several sand fly salivary proteins have been shown to be immunogenic upon multiple contacts with a mammalian host. Immunization with single immunogenic salivary proteins or exposure to uninfected bites can produce protective immune responses against leishmaniasis. These sand fly salivary proteins induce cellular immune responses and/or antibodies. Antibodies to saliva are not required for protection in a mouse model against leishmaniasis. A strong body of evidence points to the role for saliva-specific T cells producing IFN-γ in the form of a delayed-type hypersensitivity reaction at the bite site as the main protective response. Herein, we review immunity to sand fly salivary proteins in the context of its vector-parasite-host combinations and vaccine potential, as well as some recent advances to shed light on the mechanism of how an immune response to sand fly saliva protects against leishmaniasis.

Adjuvant activity of peanut, cottonseed and rice oils on cellular and humoral response

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Erika Freitas

2013-04-01

Full Text Available The potentiality of the usage of vegetable oils such as soybean, corn, olive, sesame, murici seed, rapeseed, linseed, rice and cashew nuts as adjuvant of the humoral and cellular immune response has been recently shown. In the present work, besides of evaluating the adjuvant action of peanut, cottonseed and rice oils on humoral and cellular immune responses against ovalbumin (OVA we also evaluated the protective immune response induced by Leishmania antigens. The peanut oil significantly increased the synthesis of anti-ovalbumin antibodies in the primary response, but it did not favor cellular response. Concerning mice immunized with L. amazonensis antigens emulsified with peanut oil exacerbated skin lesions and lymph node parasite load what suggests stimulation of the Th2 immune response and down regulation of Th1 response. The cottonseed oil was shown to have adjuvant effect to the humoral response, stimulating a secondary response and also favored the delayed-type hypersensitivity (DTH response to OVA. The rice oil stimulated a strong DTH reaction to OVA and enhanced the synthesis of antibodies after the third dose. Mice immunized with L. amazonensis antigens emulsified with rice oil or cotton seed oil were protected from developing skin lesions and lymph node parasite load. These results emphasize the interest and importance of the vegetable oils as tools in different procedures of immunization and their differential role in relation to the other adjuvant under usage.

Aberrant cellular immune responses in humans infected persistently with parvovirus B19

DEFF Research Database (Denmark)

Isa, Adiba; Norbeck, Oscar; Hirbod, Taha

2006-01-01

A subset of parvovirus B19 (B19) infected patients retains the infection for years, as defined by detection of B19 DNA in bone marrow. Thus far, analysis of B19-specific humoral immune responses and viral genome variations has not revealed a mechanism for the absent viral clearance. In this study......, ex-vivo cellular immune responses were assessed by enzyme linked immunospot assay mounted against the majority of the translated viral genome. Compared to seropositive healthy individuals, individuals with B19 persistence (2-8 years) showed larger number of responses to the structural proteins (P = 0.......0022), whereas responses to the non-structural protein were of lower magnitude (P = 0.012). These observations provide the first findings of immunological discrepancies between individuals with B19 persistence and healthy individuals, findings that may reflect both failed immunity and antigenic exhaustion....

Protection against Amoebic Liver Abscess in Hamster by Intramuscular Immunization with an Autographa californica Baculovirus Driving the Expression of the Gal-Lectin LC3 Fragment

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Dulce María Meneses-Ruiz

2015-01-01

Full Text Available In a previous study, we demonstrated that oral immunization using Autographa californica baculovirus driving the expression of the Gal-lectin LC3 fragment (AcNPV-LC3 of Entamoeba histolytica conferred protection against ALA development in hamsters. In this study, we determined the ability of AcNPV-LC3 to protect against ALA by the intramuscular route as well as the liver immune response associated with protection. Results showed that 55% of hamsters IM immunized with AcNPV-LC3 showed sterile protection against ALA, whereas other 20% showed reduction in the size and extent of abscesses, resulting in some protection in 75% of animals compared to the sham control group. Levels of protection showed a linear correlation with the development and intensity of specific antiamoeba cellular and humoral responses, evaluated in serum and spleen of hamsters, respectively. Evaluation of the Th1/Th2 cytokine patterns expressed in the liver of hamsters showed that sterile protection was associated with the production of high levels of IFNγ and IL-4. These results suggest that the baculovirus system is equally efficient by the intramuscular as well as the oral routes for ALA protection and that the Gal-lectin LC3 fragment is a highly protective antigen against hepatic amoebiasis through the local induction of IFNγ and IL-4.

Alterations of Cellular Immune Reactions in Crew Members Overwintering in the Antarctic Research Station Concordia

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Crucian, Brian; Feuerecker, Matthias; Moreels, Marjan; Crucian, Brian; Kaufmann, Ines; Salam, Alex Paddy; Rybka, Alex; Ulrike, Thieme; Quintens, Roel; Sams, Clarence F.;

Studies on the cellular immune response in patients with upper urinary tract carcinoma compawed with those in patients with bladder carcinoma and it's postoperative change

International Nuclear Information System (INIS)

Sakai, Shunsuke

1980-01-01

Non-specific cellular immunity of patients with upper urinary tract carcinoma was studied by PPD reaction (in vivo or in vitro), lymphocytes subpopulation and macrophage migration inhibition test and the results were compared with those of patients with bladder carcinoma or benign urological diseases. 1) The preoperative cellular immunity of the malignant tumor group gave low values as compared to that in the benign disease group. Although the cellular immunity of patients with renal cell carcinoma showed no difference in the points of their grade and stage, significant differences were noted in patients with bladder carcinoma. The patients with renal pelvic and ureter carcinoma appeared to be similar to the patients with bladder carcinoma in the aspects of immune reactions. 2) In the majority of patients with upper urinary tract and bladder carcinoma, the cellular immunity after complete removal of the carcinoma gave an increased value of each marker as compared to the preoperative value. 3) The cellular immunity after irradiation decreased in the majority of the cases in terms of PPD reaction and T-cell ratio in lymphocyte subpopulation. Irradiation of 4000 - 6000 Rad. showed greater influence on T-cell than on B-cell, but influence of irradiation on cellular immunity was not different by irradiation dose. 4) The cellular immunity indicated decreased values for one to two months after discontinuation of irradiation, but then it showed a tendency to increase in terms of PPD and lymphocytes subpopulation in the patients with satisfactory postoperative courses. 5) Through the pre and postoperative courses, the immunity of the carcinomatous stage seems to be reflected better by the T-cell ratio than by the absolute number of T-cell. It is likely that macrophage migration inhibition test shows much sharper reaction than PPD reaction. (author)

Immunization with the recombinant antigen Ss-IR induces protective immunity to infection with Strongyloides stercoralis in mice.

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Abraham, David; Hess, Jessica A; Mejia, Rojelio; Nolan, Thomas J; Lok, James B; Lustigman, Sara; Nutman, Thomas B

2011-10-19

Human intestinal infections with the nematode Strongyloides stercoralis remain a significant problem worldwide and a vaccine would be a useful addition to the tools available to prevent and control this infection. The goal of this study was to test single antigens for their efficacy in a vaccine against S. stercoralis larvae in mice. Alum was used as the adjuvant in these studies and antigens selected for analysis were either recognized by protective human IgG (Ss-TMY-1, Ss-EAT-6, and Ss-LEC-5) or were known to be highly immunogenic in humans (Ss-NIE-1 and Ss-IR). Only mice immunized with the Ss-IR antigen demonstrated a significant decrease of approximately 80% in the survival of larval parasites in the challenge infection. Antibodies, recovered from mice with protective immunity to S. stercoralis after immunization with Ss-IR, were used to locate the antigen in the larvae. Confocal microscopy revealed that IgG from mice immunized with Ss-IR bound to the surface of the parasites and observations by electron microscopy indicated that IgG bound to granules in the glandular esophagus. Serum collected from mice immunized with Ss-IR passively transferred immunity to naïve mice. These studies demonstrate that Ss-IR, in combination with alum, induces high levels of protective immunity through an antibody dependent mechanism and may therefore be suitable for further development as a vaccine against human strongyloidiasis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Distributed Computations Environment Protection Using Artificial Immune Systems

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A. V. Moiseev

2011-12-01

Full Text Available In this article the authors describe possibility of artificial immune systems applying for distributed computations environment protection from definite types of malicious impacts.

Induction of protective immunity against toxoplasmosis in mice by ...

African Journals Online (AJOL)

The results showed that mice immunized by pcROP1 with or without alum produced high Th1 immune response compared with control groups. This type of DNA vaccine prolonged slightly the survival time. The current study showed that ROP1 DNA vaccine can induced partial protective response against toxoplasmosis.

Protective immunity to UV radiation-induced skin tumours induced by skin grafts and epidermal cells

International Nuclear Information System (INIS)

Ronald Sluyter; Kylie S Yuen; Gary M Halliday

2001-01-01

There is little evidence that cutaneous dendritic cells (DC), including epidermal Langerhans cells (LC), can induce immunity to UV radiation (UVR)-induced skin tumours. Here, it is shown that cells within skin can induce protective antitumour immunity against a UVR-induced fibrosarcoma. Transplantation of the skin overlying subcutaneous tumours onto naive recipients could induce protective antitumour immunity, probably because the grafting stimulated the tumour Ag-loaded DC to migrate to local lymph nodes. This suggests that cutaneous APC can present tumour Ag to induce protective antitumour immunity. Previously, it has been shown that immunization of mice with MHC class II+ epidermal cells (EC) pulsed with tumour extracts could induce delayed-type hypersensitivity against tumour cells. Here, this same immunization protocol could induce protective immunity against a minimum tumorigenic dose of UVR-induced fibrosarcoma cells, but not higher doses. Epidermal cells obtained from semiallogeneic donors and pulsed with tumour extract could also induce protective immunity. However, presentation of BSA Ag from the culture medium was found to contribute to this result using semiallogeneic EC. The results suggest that LC overlying skin tumours may be able to induce protective immunity to UVR-induced tumours if stimulated to migrate from the skin. Copyright (2001) Australasian Society of Immunology Inc

Effect of ionizing radiation on humoral and cellular immunity in pigs vaccinated against Aujeszky's disease

International Nuclear Information System (INIS)

Bartoszcze, M.; Roszkowski, J.

1991-01-01

An effect of ionizing radiation on the immune response in pigs of both sexes weighing 35 kg vaccinated with an attenuated Aujeszky's disease virus was investigated. Ionizing radiation in a dose of 200 or 400 r reduced the number of IgM and IgG antibodies produced in vaccinated pigs. Additionally, the 400 r dose delyed the cellular immune response. No effect of the radiation on a clinical course of postvaccinal reaction was found

Replicating rather than nonreplicating adenovirus-human immunodeficiency virus recombinant vaccines are better at eliciting potent cellular immunity and priming high-titer antibodies.

Science.gov (United States)

Peng, Bo; Wang, Liqun Rejean; Gómez-Román, Victor Raúl; Davis-Warren, Alberta; Montefiori, David C; Kalyanaraman, V S; Venzon, David; Zhao, Jun; Kan, Elaine; Rowell, Thomas J; Murthy, Krishna K; Srivastava, Indresh; Barnett, Susan W; Robert-Guroff, Marjorie

2005-08-01

A major challenge in combating the human immunodeficiency virus (HIV) epidemic is the development of vaccines capable of inducing potent, persistent cellular immunity and broadly reactive neutralizing antibody responses to HIV type 1 (HIV-1). We report here the results of a preclinical trial using the chimpanzee model to investigate a combination vaccine strategy involving sequential priming immunizations with different serotypes of adenovirus (Ad)/HIV-1(MN)env/rev recombinants and boosting with an HIV envelope subunit protein, oligomeric HIV(SF162) gp140deltaV2. The immunogenicities of replicating and nonreplicating Ad/HIV-1(MN)env/rev recombinants were compared. Replicating Ad/HIV recombinants were better at eliciting HIV-specific cellular immune responses and better at priming humoral immunity against HIV than nonreplicating Ad-HIV recombinants carrying the same gene insert. Enhanced cellular immunity was manifested by a greater frequency of HIV envelope-specific gamma interferon-secreting peripheral blood lymphocytes and better priming of T-cell proliferative responses. Enhanced humoral immunity was seen in higher anti-envelope binding and neutralizing antibody titers and better induction of antibody-dependent cellular cytotoxicity. More animals primed with replicating Ad recombinants mounted neutralizing antibodies against heterologous R5 viruses after one or two booster immunizations with the mismatched oligomeric HIV-1(SF162) gp140deltaV2 protein. These results support continued development of the replicating Ad-HIV recombinant vaccine approach and suggest that the use of replicating vectors for other vaccines may prove fruitful.

Vaccination with a DNA vaccine encoding Toxoplasma gondii ROP54 induces protective immunity against toxoplasmosis in mice.

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Yang, Wen-Bin; Zhou, Dong-Hui; Zou, Yang; Chen, Kai; Liu, Qing; Wang, Jin-Lei; Zhu, Xing-Quan; Zhao, Guang-Hui

2017-12-01

Toxoplasma gondii is an obligatory intracellular protozoan, which infects most of the warm-blooded animals, causing serious public health problems and enormous economic losses worldwide. The rhoptry effector protein 54 (ROP54) has been indicated as a virulence factor that promotes Toxoplasma infection by modulating GBP2 loading onto parasite-containing vacuoles, which can modulate some aspects of the host immune response. In order to evaluate the immuno-protective value of ROP54, we constructed a eukaryotic recombinant plasmid expressing T. gondii ROP54 and intramuscularly immunized Kunming mice with this recombinant plasmid against acute and chronic toxoplasmosis. All mice immunized with pVAX-ROP54 elicited a high level of specific antibody responses, a significant increase of lymphocyte proliferation, and a significant level of Th1-type cytokines (IFN-γ, IL-2 and IL-12p70), in addition to an increased production of Th2-type cytokines (IL-4 and IL-10). These results demonstrated that pVAX-ROP54 induced significant cellular and humoral (Th1/Th2) immune responses, which extended the survival time (13.0±1.15days for pVAX-ROP54 vs 6.7±0.48days for pVAX I, 6.8±0.42days for PBS and 6.5±0.53 for blank control) and significantly reduced cyst burden (35.9% for pVAX-ROP54, 1% for pVAX I and 2% for PBS, compared with blank control) of immunized mice. These results indicate that the recombinant ROP54 plasmid can provide partial protection and might be a potential vaccine candidate against acute and chronic toxoplasmosis. Copyright © 2017 Elsevier B.V. All rights reserved.

"The Impact of Mycobacterium tuberculosis Immune Evasion on Protective Immunity: Implications for TB Vaccine Design" - Meeting report.

Science.gov (United States)

Boggiano, Cesar; Eichelberg, Katrin; Ramachandra, Lakshmi; Shea, Jaqueline; Ramakrishnan, Lalita; Behar, Samuel; Ernst, Joel D; Porcelli, Steven A; Maeurer, Markus; Kornfeld, Hardy

2017-06-14

Tuberculosis (TB) is the major cause of death from infectious diseases around the world, particularly in HIV infected individuals. TB vaccine design and development have been focused on improving Bacille Calmette-Guérin (BCG) and evaluating recombinant and viral vector expressed Mycobacterium tuberculosis (Mtb) proteins, for boosting BCG-primed immunity, but these approaches have not yet yielded significant improvements over the modest effects of BCG in protecting against infection or disease. On March 7-8, 2016, the National Institute of Allergy and Infectious Diseases (NIAID) convened a workshop on "The Impact of Mtb Immune Evasion on Protective Immunity: Implications for TB Vaccine Design" with the goal of defining immune mechanisms that could be targeted through novel research approaches, to inform vaccine design and immune therapeutic interventions for prevention of TB. The workshop addressed early infection events, the impact of Mtb evolution on the development and maintenance of an adaptive immune response, and the factors that influence protection against and progression to active disease. Scientific gaps and areas of study to revitalize and accelerate TB vaccine design were discussed and prioritized. These included a comprehensive evaluation of innate and Mtb-specific adaptive immune responses in the lung at different stages of disease; determining the role of B cells and antibodies (Abs) during Mtb infection; development of better assays to measure Mtb burden following exposure, infection, during latency and after treatment, and approaches to improving current animal models to study Mtb immunogenicity, TB disease and transmission. Copyright © 2017.

Eosinophils mediate protective immunity against secondary nematode infection.

Science.gov (United States)

Huang, Lu; Gebreselassie, Nebiat G; Gagliardo, Lucille F; Ruyechan, Maura C; Luber, Kierstin L; Lee, Nancy A; Lee, James J; Appleton, Judith A

2015-01-01

Eosinophils are versatile cells that regulate innate and adaptive immunity, influence metabolism and tissue repair, and contribute to allergic lung disease. Within the context of immunity to parasitic worm infections, eosinophils are prominent yet highly varied in function. We have shown previously that when mice undergo primary infection with the parasitic nematode Trichinella spiralis, eosinophils play an important immune regulatory role that promotes larval growth and survival in skeletal muscle. In this study, we aimed to address the function of eosinophils in secondary infection with T. spiralis. By infecting eosinophil-ablated mice, we found that eosinophils are dispensable for immunity that clears adult worms or controls fecundity in secondary infection. In contrast, eosinophil ablation had a pronounced effect on secondary infection of skeletal muscle by migratory newborn larvae. Restoring eosinophils to previously infected, ablated mice caused them to limit muscle larvae burdens. Passive immunization of naive, ablated mice with sera or Ig from infected donors, together with transfer of eosinophils, served to limit the number of newborn larvae that migrated in tissue and colonized skeletal muscle. Results from these in vivo studies are consistent with earlier findings that eosinophils bind to larvae in the presence of Abs in vitro. Although our previous findings showed that eosinophils protect the parasite in primary infection, these new data show that eosinophils protect the host in secondary infection. Copyright © 2014 by The American Association of Immunologists, Inc.

The role of MPL and imiquimod adjuvants in enhancement of immune response and protection in BALB/c mice immunized with soluble Leishmania antigen (SLA) encapsulated in nanoliposome.

Science.gov (United States)

Emami, Tara; Rezayat, Seyed Mahdi; Khamesipour, Ali; Madani, Rasool; Habibi, Gholamreza; Hojatizade, Mansure; Jaafari, Mahmoud Reza

2018-04-01

Adjuvants play an essential role in the induction of immunity against leishmaniasis. In this study, monophosphoryl lipid A (MPL) and imiquimod (IMQ) were used as TLR ligands adjuvants to enhance immunogenicity and rate of protection against leishmaniasis. Nanoliposomes containing soluble Leishmania antigens (SLA) and adjuvants were consisted of DSPC, DSPG and Chol prepared by using lipid film method followed by bath sonication. The size of nanoliposomes was around 95 nm and their zeta potential was negative. BALB/c mice were immunized by liposomal formulations of lip/SLA, lip/MPL/SLA, lip/IMQ/SLA, lip/MPL/IMQ/SLA, lip/SLA + lip/IMQ, lip/SLA + lip/MPL, lip/SLA + lip/MPL/IMQ and five controls of SLA, lip/MPL, lip/IMQ, lip/MPL/IMQ and buffer by subcutaneously (SC) injections, three times in 2 weeks intervals. The synergic effect of two adjuvants when they are used in one formulation showed significantly (p MPL and IMQ adjuvants and antigen in nanoliposome carrier could be an appropriate delivery system to induce cellular immunity pathway against leishmaniasis.

Cellular and humoral immune responses in sheep vaccinated with candidate antigens MAP2698c and MAP3567 from Mycobacterium avium subspecies paratuberculosis

Science.gov (United States)

Gurung, Ratna B.; Purdie, Auriol C.; Whittington, Richard J.; Begg, Douglas J.

2014-01-01

Control of Johne's disease, caused by Mycobacterium avium subspecies paratuberculosis (MAP) in ruminants using commercially available vaccine reduces production losses, mortality, fecal shedding and histopathological lesions but does not provide complete protection from infection and interferes with serological diagnosis of Johne's disease and bovine tuberculosis. At this time no recombinant antigens have been found to provide superior protection compared to whole killed or live-attenuated MAP vaccines. Therefore, there is a need to evaluate more candidate MAP antigens. In this study recombinant MAP antigens MAP2698c and MAP3567 were formulated with four different MONTANIDE™ (ISA 50V2, 61VG, 71VG, and 201VG) adjuvants and evaluated for their ability to produce specific immune responses in vaccinated sheep. The cellular immune response was measured with an interferon-gamma (IFN-γ) release assay and the humoral immune response was measured by antibody detection enzyme linked immunosorbent assay. Recombinant vaccine formulation with the antigen MAP2698c and MONTANIDE™ ISA 201VG adjuvant produced strong whole-MAP as well as MAP2698c-specific IFN-γ responses in a high proportion of the vaccinated sheep. The formulation caused less severe injection site lesions in comparison to other formulations. The findings from this study suggest that the MAP2698c + 201VG should be evaluated in a challenge trial to determine the efficacy of this vaccine candidate. PMID:25077074

A genetically engineered live-attenuated simian-human immunodeficiency virus that co-expresses the RANTES gene improves the magnitude of cellular immunity in rhesus macaques

International Nuclear Information System (INIS)

Shimizu, Yuya; Inaba, Katsuhisa; Kaneyasu, Kentaro; Ibuki, Kentaro; Himeno, Ai; Okoba, Masashi; Goto, Yoshitaka; Hayami, Masanori; Miura, Tomoyuki; Haga, Takeshi

2007-01-01

Regulated-on-activation-normal-T-cell-expressed-and-secreted (RANTES), a CC-chemokine, enhances antigen-specific T helper (Th) type-1 responses against HIV-1. To evaluate the adjuvant effects of RANTES against HIV vaccine candidate in SHIV-macaque models, we genetically engineered a live-attenuated SHIV to express the RANTES gene (SHIV-RANTES) and characterized the virus's properties in vivo. After the vaccination, the plasma viral loads were same in the SHIV-RANTES-inoculated monkeys and the parental nef-deleted SHIV (SHIV-NI)-inoculated monkeys. SHIV-RANTES provided some immunity in monkeys by remarkably increasing the antigen-specific CD4 + Th cell-proliferative response and by inducing an antigen-specific IFN-γ ELISpot response. The magnitude of the immunity in SHIV-RANTES-immunized animals, however, failed to afford greater protection against a heterologous pathogenic SHIV (SHIV-C2/1) challenge compared to control SHIV-NI-immunized animals. SHIV-RANTES immunized monkeys, elicited robust cellular CD4 + Th responses and IFN-γ ELISpot responses after SHIV-C2/1 challenge. These findings suggest that the chemokine RANTES can augment vaccine-elicited, HIV-specific CD4 + T cell responses

Cellular immune responses against CT7 (MAGE-C1) and humoral responses against other cancer-testis antigens in multiple myeloma patients.

Science.gov (United States)

Lendvai, Nikoletta; Gnjatic, Sacha; Ritter, Erika; Mangone, Michael; Austin, Wayne; Reyner, Karina; Jayabalan, David; Niesvizky, Ruben; Jagannath, Sundar; Bhardwaj, Nina; Chen-Kiang, Selina; Old, Lloyd J; Cho, Hearn Jay

2010-01-29

The type I melanoma antigen gene (MAGE) proteins CT7 (MAGE-C1) and MAGE-A3 are commonly expressed in multiple myeloma (MM), and their expression correlates with increased plasma cell proliferation and poor clinical outcome. They belong to the cancer-testis antigen (CTAg) group of tumor-associated proteins, some of which elicit spontaneous immune responses in cancer patients. CT7 and MAGE-A3 are promising antigenic targets for therapeutic tumor vaccines in myeloma; therefore, it is critical to determine if they are immunogenic in MM patients. We analyzed cellular and humoral immune responses against CTAgs in patients with plasma cell dyscrasias: MM, monoclonal gammopathy of undetermined significance (MGUS), and Waldenström's macroglobulinemia (WM). Bone marrow lymphocytes from two of four untreated MM patients exhibited CT7-specific cellular immune responses as measured by an autologous cellular immunity assay, the first such immune response to CT7 to be reported in cancer patients. Sera from 24 patients were screened by ELISA for humoral immune responses to CTAgs. Two patients with MM demonstrated positive titers, one for MAGE-A1 and the other for SSX1. These data demonstrate that CTAgs, particularly CT7, are immunogenic in MM patients and merit further exploration as targets of immunological therapy in MM.

Transient expression of protein tyrosine phosphatases encoded in Cotesia plutellae bracovirus inhibits insect cellular immune responses

Science.gov (United States)

Ibrahim, Ahmed M. A.; Kim, Yonggyun

2008-01-01

Several immunosuppressive factors are associated with parasitism of an endoparasitoid wasp, Cotesia plutellae, on the diamondback moth, Plutella xylostella. C. plutellae bracovirus (CpBV) encodes a large number of putative protein tyrosine phosphatases (PTPs), which may play a role in inhibiting host cellular immunity. To address this inhibitory hypothesis of CpBV-PTPs, we performed transient expression of individual CpBV-PTPs in hemocytes of the beet armyworm, Spodoptera exigua, and analyzed their cellular immune responses. Two different forms of CpBV-PTPs were chosen and cloned into a eukaryotic expression vector under the control of the p10 promoter of baculovirus: one with the normal cysteine active site (CpBV-PTP1) and the other with a mutated active site (CpBV-PTP5). The hemocytes transfected with CpBV-PTP1 significantly increased in PTP activity compared to control hemocytes, but those with CpBV-PTP5 exhibited a significant decrease in the PTP activity. All transfected hemocytes exhibited a significant reduction in both cell spreading and encapsulation activities compared to control hemocytes. Co-transfection of CpBV-PTP1 together with its double-stranded RNA reduced the messenger RNA (mRNA) level of CpBV-PTP1 and resulted in recovery of both hemocyte behaviors. This is the first report demonstrating that the polydnaviral PTPs can manipulate PTP activity of the hemocytes to interrupt cellular immune responses.

Mechanisms of protective immunity against Schistosoma mansoni infection in mice vaccinated with irradiated cercariae. V. Anamnestic cellular and humoral responses following challenge infection

International Nuclear Information System (INIS)

Correa-Oliveira, R.; Sher, A.; James, S.L.

1984-01-01

Mice vaccinated with radiation-attenuated cercariae display low levels of cellular and humoral immune responses toward schistosomulum antigens, as measured in vitro by lymphocyte blastogenesis and quantitation of anti-larval antibodies by indirect immunofluorescence. Both responses wane with time after vaccination. However subsequent challenge infection provokes immune responses of classical anamnestic character, being both more rapid in appearance and of greater magnitude. Antigen responsive cells appear in lymph nodes draining the challenge site within 24 hours after infection. Both circulating anti-schistosomulum surface antibodies as well as cytophilic IgE anti-worm antigen antibodies increase substantially by 1 week after challenge. All of the anamnestic circulating antibodies belong to the IgG class. Those findings support the concept that vaccine-induced resistance to Schistosoma mansoni infection involves sensitized T and B lymphocytes, and point to the possible role of post-challenge anamnestic responses in the effector mechanism of parasite killing in this model

Mucosal Immunity and Protective Efficacy of Intranasal Inactivated Influenza Vaccine Is Improved by Chitosan Nanoparticle Delivery in Pigs

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Santosh Dhakal

2018-05-01

Full Text Available Annually, swine influenza A virus (SwIAV causes severe economic loss to swine industry. Currently used inactivated SwIAV vaccines administered by intramuscular injection provide homologous protection, but limited heterologous protection against constantly evolving field viruses, attributable to the induction of inadequate levels of mucosal IgA and cellular immune responses in the respiratory tract. A novel vaccine delivery platform using mucoadhesive chitosan nanoparticles (CNPs administered through intranasal (IN route has the potential to elicit strong mucosal and systemic immune responses in pigs. In this study, we evaluated the immune responses and cross-protective efficacy of IN chitosan encapsulated inactivated SwIAV vaccine in pigs. Killed SwIAV H1N2 (δ-lineage antigens (KAg were encapsulated in chitosan polymer-based nanoparticles (CNPs-KAg. The candidate vaccine was administered twice IN as mist to nursery pigs. Vaccinates and controls were then challenged with a zoonotic and virulent heterologous SwIAV H1N1 (γ-lineage. Pigs vaccinated with CNPs-KAg exhibited an enhanced IgG serum antibody and mucosal secretory IgA antibody responses in nasal swabs, bronchoalveolar lavage (BAL fluids, and lung lysates that were reactive against homologous (H1N2, heterologous (H1N1, and heterosubtypic (H3N2 influenza A virus strains. Prior to challenge, an increased frequency of cytotoxic T lymphocytes, antigen-specific lymphocyte proliferation, and recall IFN-γ secretion by restimulated peripheral blood mononuclear cells in CNPs-KAg compared to control KAg vaccinates were observed. In CNPs-KAg vaccinated pigs challenged with heterologous virus reduced severity of macroscopic and microscopic influenza-associated pulmonary lesions were observed. Importantly, the infectious SwIAV titers in nasal swabs [days post-challenge (DPC 4] and BAL fluid (DPC 6 were significantly (p < 0.05 reduced in CNPs-KAg vaccinates but not in KAg vaccinates when compared

Galleria mellonella larvae are capable of sensing the extent of priming agent and mounting proportionatal cellular and humoral immune responses.

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Wu, Gongqing; Xu, Li; Yi, Yunhong

2016-06-01

Larvae of Galleria mellonella are useful models for studying the innate immunity of invertebrates or for evaluating the virulence of microbial pathogens. In this work, we demonstrated that prior exposure of G. mellonella larvae to high doses (1×10(4), 1×10(5) or 1×10(6) cells/larva) of heat-killed Photorhabdus luminescens TT01 increases the resistance of larvae to a lethal dose (50 cells/larva) of viable P. luminescens TT01 infection administered 48h later. We also found that the changes in immune protection level were highly correlated to the changes in levels of cellular and humoral immune parameters when priming the larvae with different doses of heat-killed P. luminescens TT01. Priming the larvae with high doses of heat-killed P. luminescens TT01 resulted in significant increases in the hemocytes activities of phagocytosis and encapsulation. High doses of heat-killed P. luminescens TT01 also induced an increase in total hemocyte count and a reduction in bacterial density within the larval hemocoel. Quantitative real-time PCR analysis showed that genes coding for cecropin and gallerimycin and galiomycin increased in expression after priming G. mellonella with heat-killed P. luminescens TT01. All the immune parameters changed in a dose-dependent manner. These results indicate that the insect immune system is capable of sensing the extent of priming agent and mounting a proportionate immune response. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Alteration of cellular immune responses in the seastar Asterias rubens following dietary exposure to cadmium

International Nuclear Information System (INIS)

Coteur, G.; Gillan, D.; Pernet, Ph.; Dubois, Ph.

2005-01-01

Several parameters of cellular immunity in seastars fed Cd-contaminated mussels were analyzed. The accumulation of cadmium in the seastars did not alter the concentration of amoebocytes in the coelomic fluid. On the contrary, the immune cells showed a reduced phagocytic activity and an increased production of reactive oxygen species. These effects may lead to an inability of the seastars to cope with bacterial infections and to oxidative damages to self tissue that could threaten the survival of the animals

Glycan elongation beyond the mucin associated Tn antigen protects tumor cells from immune-mediated killing.

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Caroline B Madsen

Full Text Available Membrane bound mucins are up-regulated and aberrantly glycosylated during malignant transformation in many cancer cells. This results in a negatively charged glycoprotein coat which may protect cancer cells from immune surveillance. However, only limited data have so far demonstrated the critical steps in glycan elongation that make aberrantly glycosylated mucins affect the interaction between cancer cells and cytotoxic effector cells of the immune system. Tn (GalNAc-Ser/Thr, STn (NeuAcα2-6GalNAc-Ser/Thr, T (Galβ1-3GalNAc-Ser/Thr, and ST (NeuAcα2-6Galβ1-3GalNAc-Ser/Thr antigens are recognized as cancer associated truncated glycans, and are expressed in many adenocarcinomas, e.g. breast- and pancreatic cancer cells. To investigate the role of the cancer associated glycan truncations in immune-mediated killing we created glyco-engineered breast- and pancreatic cancer cells expressing only the shortest possible mucin-like glycans (Tn and STn. Glyco-engineering was performed by zinc finger nuclease (ZFN knockout (KO of the Core 1 enzyme chaperone COSMC, thereby preventing glycan elongation beyond the initial GalNAc residue in O-linked glycans. We find that COSMC KO in the breast and pancreatic cancer cell lines T47D and Capan-1 increases sensitivity to both NK cell mediated antibody-dependent cellular-cytotoxicity (ADCC and cytotoxic T lymphocyte (CTL-mediated killing. In addition, we investigated the association between total cell surface expression of MUC1/MUC16 and NK or CTL mediated killing, and observed an inverse correlation between MUC16/MUC1 expression and the sensitivity to ADCC and CTL-mediated killing. Together, these data suggest that up-regulation of membrane bound mucins protects cells from immune mediated killing, and that particular glycosylation steps, as demonstrated for glycan elongation beyond Tn and STn, can be important for fine tuning of the immune escape mechanisms in cancer cells.

T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models.

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Watson, Alan M; Klimstra, William B

2017-04-11

The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus.

Oral administration of type-II collagen peptide 250-270 suppresses specific cellular and humoral immune response in collagen-induced arthritis.

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Zhu, Ping; Li, Xiao-Yan; Wang, Hong-Kun; Jia, Jun-Feng; Zheng, Zhao-Hui; Ding, Jin; Fan, Chun-Mei

2007-01-01

Oral antigen is an attractive approach for the treatment of autoimmune and inflammatory diseases. Establishment of immune markers and methods in evaluating the effects of antigen-specific cellular and humoral immune responses will help the application of oral tolerance in the treatment of human diseases. The present article observed the effects of chicken collagen II (CII), the recombinant polymerized human collagen II 250-270 (rhCII 250-270) peptide and synthesized human CII 250-270 (syCII 250-270) peptide on the induction of antigen-specific autoimmune response in rheumatoid arthritis (RA) peripheral blood mononuclear cells (PBMC) and on the specific cellular and humoral immune response in collagen-induced arthritis (CIA) and mice fed with CII (250-270) prior to immunization with CII. In the study, proliferation, activation and intracellular cytokine production of antigen-specific T lymphocytes were simultaneously analyzed by bromodeoxyuridine (BrdU) incorporation and flow cytometry at the single-cell level. The antigen-specific antibody and antibody-forming cells were detected by ELISA and ELISPOT, respectively. CII (250-270) was found to have stimulated the response of specific lymphocytes in PBMC from RA patients, including the increase expression of surface activation antigen marker CD69 and CD25, and DNA synthesis. Mice, fed with CII (250-270) before CII immunization, had significantly lower arthritic scores than the mice immunized with CII alone, and the body weight of the former increased during the study period. Furthermore, the specific T cell activity, proliferation and secretion of interferon (IFN)-gamma in spleen cells were actively suppressed in CII (250-270)-fed mice, and the serum anti-CII, anti-CII (250-270) antibody activities and the frequency of specific antibody-forming spleen cells were significantly lower in CII (250-270)-fed mice than in mice immunized with CII alone. These observations suggest that oral administration of CII (250-270) can

Humoral immunity through immunoglobulin M protects mice from an experimental actinomycetoma infection by Nocardia brasiliensis.

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Salinas-Carmona, Mario C; Pérez-Rivera, Isabel

2004-10-01

An experimental model of infection with Nocardia brasiliensis, used as an example of a facultative intracellular pathogen, was tested. N. brasiliensis was injected into the rear foot pads of BALB/c mice to establish an infection. Within 30 days, infected animals developed a chronic actinomycetoma infection. Batch cultures of N. brasiliensis were used to purify P61, P38, and P24 antigens; P61 is a catalase, and P38 is a protease with strong caseinolytic activity. Active and passive immunizations of BALB/c mice with these three purified soluble antigens were studied. Protection was demonstrated for actively immunized mice. However, immunity lasted only 30 days. Other groups of immunized mice were bled at different times, and their sera were passively transferred to naive recipients that were then infected with N. brasiliensis. Sera collected 5, 6, and 7 days after donor immunization conferred complete, long-lasting protection. The protective effect of passive immunity decreased when sera were collected 2 weeks after donor immunization. However, neither the early sera (1-, 2-, and 3-day sera) nor the later sera (30- or 45-day sera) prevented the infection. Hyperimmune sera with the highest levels of immunoglobulin G (IgG) to N. brasiliensis antigens did not protect at all. The antigens tested induced two IgM peaks. The first peak was present 3 days after immunization but was not antigen specific and did not transfer protection. The second peak was evident 7 days after immunization, was an IgM response, was antigen specific, and conferred protection. This results clearly demonstrate that IgM antibodies protect the host against a facultative intracellular bacterium.

VAR2CSA and protective immunity against pregnancy-associated Plasmodium falciparum malaria

DEFF Research Database (Denmark)

Hviid, L; Salanti, A

2007-01-01

People living in areas with stable transmission of P. falciparum parasites acquire protective immunity to malaria over a number of years and following multiple disease episodes. Immunity acquired this way is mediated by IgG with specificity for parasite-encoded, clonally variant surface antigens...... that the selective placental accumulation of IEs that characterizes pregnancy-associated malaria (PAM) is caused by an immunologically and functionally unique subset of VSA (VSAPAM) that is only expressed by parasites infecting pregnant women, and that protective immunity to PAM is mediated by IgG with specificity...

Protective immunity by oral immunization with heat-killed Shigella strains in a guinea pig colitis model.

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Barman, Soumik; Koley, Hemanta; Ramamurthy, Thandavarayan; Chakrabarti, Manoj Kumar; Shinoda, Sumio; Nair, Gopinath Balakrish; Takeda, Yoshifumi

2013-11-01

The protective efficacy of and immune response to heat-killed cells of monovalent and hexavalent mixtures of six serogroups/serotypes of Shigella strains (Shigella dysenteriae 1, Shigella flexneri 2a, S. flexneri 3a, S. flexneri 6, Shigella boydii 4, and Shigella sonnei) were examined in a guinea pig colitis model. A monovalent or hexavalent mixture containing 1 × 10(7) of each serogroup/serotype of heat-killed Shigella cells was administered orally on Days 0, 7, 14 and 21. On Day 28, the immunized animals were challenged rectally with 1 × 10(9) live virulent cells of each of the six Shigella serogroups/serotypes. In all immunized groups, significant levels of protection were observed after these challenges. The serum titers of IgG and IgA against the lipopolysaccharide of each of the six Shigella serogroups/serotypes increased exponential during the course of immunization. High IgA titers against the lipopolysaccharide of each of the six Shigella serogroups/serotypes were also observed in intestinal lavage fluid from all immunized animals. These data indicate that a hexavalent mixture of heat-killed cells of the six Shigella serogroups/serotypes studied would be a possible broad-spectrum candidate vaccine against shigellosis. © 2013 The Societies and Wiley Publishing Asia Pty Ltd.

The effect of oral consumption of shark cartilage on the cellular immune responses of cancer patients

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somaye Shahrokhi

2006-11-01

Conclusion: It seems that shark cartilage could help strengthen cellular immunity which is important in tumor regression in breast cancer patients. So we suppose that it could be a good candidate for cancer treatment along with conventional medicine.

Room Temperature Stable PspA-Based Nanovaccine Induces Protective Immunity

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Danielle A. Wagner-Muñiz

2018-03-01

Full Text Available Streptococcus pneumoniae is a major causative agent of pneumonia, a debilitating disease particularly in young and elderly populations, and is the leading worldwide cause of death in children under the age of five. While there are existing vaccines against S. pneumoniae, none are protective across all serotypes. Pneumococcal surface protein A (PspA, a key virulence factor of S. pneumoniae, is an antigen that may be incorporated into future vaccines to address the immunological challenges presented by the diversity of capsular antigens. PspA has been shown to be immunogenic and capable of initiating a humoral immune response that is reactive across approximately 94% of pneumococcal strains. Biodegradable polyanhydrides have been studied as a nanoparticle-based vaccine (i.e., nanovaccine platform to stabilize labile proteins, to provide adjuvanticity, and enhance patient compliance by providing protective immunity in a single dose. In this study, we designed a room temperature stable PspA-based polyanhydride nanovaccine that eliminated the need for a free protein component (i.e., 100% encapsulated within the nanoparticles. Mice were immunized once with the lead nanovaccine and upon challenge, presented significantly higher survival rates than animals immunized with soluble protein alone, even with a 25-fold reduction in protein dose. This lead nanovaccine formulation performed similarly to protein adjuvanted with Alum, however, with much less tissue reactogenicity at the site of immunization. By eliminating the free PspA from the nanovaccine formulation, the lead nanovaccine was efficacious after being stored dry for 60 days at room temperature, breaking the need for maintaining the cold chain. Altogether, this study demonstrated that a single dose PspA-based nanovaccine against S. pneumoniae induced protective immunity and provided thermal stability when stored at room temperature for at least 60 days.

T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models

Science.gov (United States)

Watson, Alan M.; Klimstra, William B.

2017-01-01

The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus. PMID:28398253

Immunity to Babesia in mice I. Adoptive transfer of immunity to Babesia rodhaini with immune spleen cells and the effect of irradiation on the protection of immune mice

NARCIS (Netherlands)

Kuil, H.; Zivkovic, D.; Seinen, W.; Albers-van Bemmel, C.M.G.; Speksnijder, J.E.

1984-01-01

Immunisation of Balb/c mice against Babesia rodhaini by an amicarbalide- controlled infection resulted in a solid immunity which lasted for 216 days. With spleen cells of immune mice protection could be transferred both to naive mice pretreated with cyclophosphamide. Treatment of naive mice with

Innate immunity and cellular senescence: The good and the bad in the developmental and aged brain.

Science.gov (United States)

Santoro, Antonietta; Spinelli, Chiara Carmela; Martucciello, Stefania; Nori, Stefania Lucia; Capunzo, Mario; Puca, Annibale Alessandro; Ciaglia, Elena

2018-03-01

Ongoing studies evidence cellular senescence in undifferentiated and specialized cells from tissues of all ages. Although it is believed that senescence plays a wider role in several stress responses in the mature age, its participation in certain physiological and pathological processes throughout life is coming to light. The "senescence machinery" has been observed in all brain cell populations, including components of innate immunity (e.g., microglia and astrocytes). As the beneficial versus detrimental implications of senescence is an open question, we aimed to analyze the contribution of immune responses in regulatory mechanisms governing its distinct functions in healthy (development, organogenesis, danger patrolling events) and diseased brain (glioma, neuroinflammation, neurodeneration), and the putative connection between cellular and molecular events governing the 2 states. Particularly this review offers new insights into the complex roles of senescence both as a chronological event as age advances, and as a molecular mechanism of brain homeostasis through the important contribution of innate immune responses and their crosstalk with neighboring cells in brain parenchyma. We also highlight the impact of the recently described glymphatic system and brain lymphatic vasculature in the interplay between peripheral and central immune surveillance and its potential implication during aging. This will open new ways to understand brain development, its deterioration during aging, and the occurrence of several oncological and neurodegenerative diseases. ©2018 Society for Leukocyte Biology.

Induction and Subversion of Human Protective Immunity: Contrasting Influenza and Respiratory Syncytial Virus

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Stephanie Ascough

2018-03-01

Full Text Available Respiratory syncytial virus (RSV and influenza are among the most important causes of severe respiratory disease worldwide. Despite the clinical need, barriers to developing reliably effective vaccines against these viruses have remained firmly in place for decades. Overcoming these hurdles requires better understanding of human immunity and the strategies by which these pathogens evade it. Although superficially similar, the virology and host response to RSV and influenza are strikingly distinct. Influenza induces robust strain-specific immunity following natural infection, although protection by current vaccines is short-lived. In contrast, even strain-specific protection is incomplete after RSV and there are currently no licensed RSV vaccines. Although animal models have been critical for developing a fundamental understanding of antiviral immunity, extrapolating to human disease has been problematic. It is only with recent translational advances (such as controlled human infection models and high-dimensional technologies that the mechanisms responsible for differences in protection against RSV compared to influenza have begun to be elucidated in the human context. Influenza infection elicits high-affinity IgA in the respiratory tract and virus-specific IgG, which correlates with protection. Long-lived influenza-specific T cells have also been shown to ameliorate disease. This robust immunity promotes rapid emergence of antigenic variants leading to immune escape. RSV differs markedly, as reinfection with similar strains occurs despite natural infection inducing high levels of antibody against conserved antigens. The immunomodulatory mechanisms of RSV are thus highly effective in inhibiting long-term protection, with disturbance of type I interferon signaling, antigen presentation and chemokine-induced inflammation possibly all contributing. These lead to widespread effects on adaptive immunity with impaired B cell memory and reduced T cell

Induction and Subversion of Human Protective Immunity: Contrasting Influenza and Respiratory Syncytial Virus

Science.gov (United States)

Ascough, Stephanie; Paterson, Suzanna; Chiu, Christopher

2018-01-01

Respiratory syncytial virus (RSV) and influenza are among the most important causes of severe respiratory disease worldwide. Despite the clinical need, barriers to developing reliably effective vaccines against these viruses have remained firmly in place for decades. Overcoming these hurdles requires better understanding of human immunity and the strategies by which these pathogens evade it. Although superficially similar, the virology and host response to RSV and influenza are strikingly distinct. Influenza induces robust strain-specific immunity following natural infection, although protection by current vaccines is short-lived. In contrast, even strain-specific protection is incomplete after RSV and there are currently no licensed RSV vaccines. Although animal models have been critical for developing a fundamental understanding of antiviral immunity, extrapolating to human disease has been problematic. It is only with recent translational advances (such as controlled human infection models and high-dimensional technologies) that the mechanisms responsible for differences in protection against RSV compared to influenza have begun to be elucidated in the human context. Influenza infection elicits high-affinity IgA in the respiratory tract and virus-specific IgG, which correlates with protection. Long-lived influenza-specific T cells have also been shown to ameliorate disease. This robust immunity promotes rapid emergence of antigenic variants leading to immune escape. RSV differs markedly, as reinfection with similar strains occurs despite natural infection inducing high levels of antibody against conserved antigens. The immunomodulatory mechanisms of RSV are thus highly effective in inhibiting long-term protection, with disturbance of type I interferon signaling, antigen presentation and chemokine-induced inflammation possibly all contributing. These lead to widespread effects on adaptive immunity with impaired B cell memory and reduced T cell generation and

Anti-Glycoprotein G Antibodies of Herpes Simplex Virus 2 Contribute to Complete Protection after Vaccination in Mice and Induce Antibody-Dependent Cellular Cytotoxicity and Complement-Mediated Cytolysis

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Staffan Görander

2014-11-01

Full Text Available We investigated the role of antibodies against the mature portion of glycoprotein G (mgG-2 of herpes simplex virus 2 (HSV-2 in protective immunity after vaccination. Mice were immunized intramuscularly with mgG-2 and oligodeoxynucleotides containing two CpG motifs plus alum as adjuvant. All C57BL/6 mice survived and presented no genital or systemic disease. High levels of immunoglobulin G subclass 1 (IgG1 and IgG2 antibodies were detected and re-stimulated splenic CD4+ T cells proliferated and produced IFN-γ. None of the sera from immunized mice exhibited neutralization, while all sera exerted antibody-dependent cellular cytotoxicity (ADCC and complement-mediated cytolysis (ACMC activity. Passive transfer of anti-mgG-2 monoclonal antibodies, or immune serum, to naive C57BL/6 mice did not limit disease progression. Immunized B‑cell KO mice presented lower survival rate and higher vaginal viral titers, as compared with vaccinated B-cell KO mice after passive transfer of immune serum and vaccinated C57BL/6 mice. Sera from mice that were vaccinated subcutaneously and intranasally with mgG-2 presented significantly lower titers of IgG antibodies and lower ADCC and ACMC activity. We conclude that anti-mgG-2 antibodies were of importance to limit genital HSV‑2 infection. ADCC and ACMC activity are potentially important mechanisms in protective immunity, and could tentatively be evaluated in future animal vaccine studies and in clinical trials.

Acquired Protective Immunity in Atlantic Salmon Salmo salar against the Myxozoan Kudoa thyrsites Involves Induction of MHIIβ+ CD83+ Antigen-Presenting Cells.

Science.gov (United States)

Braden, Laura M; Rasmussen, Karina J; Purcell, Sara L; Ellis, Lauren; Mahony, Amelia; Cho, Steven; Whyte, Shona K; Jones, Simon R M; Fast, Mark D

2018-01-01

The histozoic myxozoan parasite Kudoa thyrsites causes postmortem myoliquefaction and is responsible for economic losses to salmon aquaculture in the Pacific Northwest. Despite its importance, little is known about the host-parasite relationship, including the host response to infection. The present work sought to characterize the immune response in Atlantic salmon during infection, recovery, and reexposure to K. thyrsites After exposure to infective seawater, infected and uninfected smolts were sampled three times over 4,275 degree-days. Histological analysis revealed infection severity decreased over time in exposed fish, while in controls there was no evidence of infection. Following a secondary exposure of all fish, severity of infection in the controls was similar to that measured in exposed fish at the first sampling time but was significantly reduced in reexposed fish, suggesting the acquisition of protective immunity. Using immunohistochemistry, we detected a population of MHIIβ + cells in infected muscle that followed a pattern of abundance concordant with parasite prevalence. Infiltration of these cells into infected myocytes preceded destruction of the plasmodium and dissemination of myxospores. Dual labeling indicated a majority of these cells were CD83 + /MHIIβ + Using reverse transcription-quantitative PCR, we detected significant induction of cellular effectors, including macrophage/dendritic cells ( mhii / cd83 / mcsf ), B cells ( igm / igt ), and cytotoxic T cells ( cd8 / nkl ), in the musculature of infected fish. These data support a role for cellular effectors such as antigen-presenting cells (monocyte/macrophage and dendritic cells) along with B and T cells in the acquired protective immune response of Atlantic salmon against K. thyrsites . Copyright © 2017 American Society for Microbiology.

Immune Protection against Lethal Fungal-Bacterial Intra-Abdominal Infections

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Lilly, Elizabeth A.; Ikeh, Melanie; Nash, Evelyn E.; Fidel, Paul L.

2018-01-01

ABSTRACT Polymicrobial intra-abdominal infections (IAIs) are clinically prevalent and cause significant morbidity and mortality, especially those involving fungi. Our laboratory developed a mouse model of IAI and demonstrated that intraperitoneal inoculation with Candida albicans or other virulent non-albicans Candida (NAC) species plus Staphylococcus aureus resulted in 70 to 80% mortality in 48 to 72 h due to robust local and systemic inflammation (sepsis). Surprisingly, inoculation with Candida dubliniensis or Candida glabrata with S. aureus resulted in minimal mortality, and rechallenge of these mice with lethal C. albicans/S. aureus (i.e., coninfection) resulted in >90% protection. The purpose of this study was to define requirements for C. dubliniensis/S. aureus-mediated protection and interrogate the mechanism of the protective response. Protection was conferred by C. dubliniensis alone or by killed C. dubliniensis plus live S. aureus. S. aureus alone was not protective, and killed S. aureus compromised C. dubliniensis-induced protection. C. dubliniensis/S. aureus also protected against lethal challenge by NAC plus S. aureus and could protect for a long-term duration (60 days between primary challenge and C. albicans/S. aureus rechallenge). Unexpectedly, mice deficient in T and B cells (Rag-1 knockouts [KO]) survived both the initial C. dubliniensis/S. aureus challenge and the C. albicans/S. aureus rechallenge, indicating that adaptive immunity did not play a role. Similarly, mice depleted of macrophages prior to rechallenge were also protected. In contrast, protection was associated with high numbers of Gr-1hi polymorphonuclear leukocytes (PMNLs) in peritoneal lavage fluid within 4 h of rechallenge, and in vivo depletion of Gr-1+ cells prior to rechallenge abrogated protection. These results suggest that Candida species can induce protection against a lethal C. albicans/S. aureus IAI that is mediated by PMNLs and postulated to be a unique form of

Immune Protection against Lethal Fungal-Bacterial Intra-Abdominal Infections

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Elizabeth A. Lilly

2018-01-01

Full Text Available Polymicrobial intra-abdominal infections (IAIs are clinically prevalent and cause significant morbidity and mortality, especially those involving fungi. Our laboratory developed a mouse model of IAI and demonstrated that intraperitoneal inoculation with Candida albicans or other virulent non-albicans Candida (NAC species plus Staphylococcus aureus resulted in 70 to 80% mortality in 48 to 72 h due to robust local and systemic inflammation (sepsis. Surprisingly, inoculation with Candida dubliniensis or Candida glabrata with S. aureus resulted in minimal mortality, and rechallenge of these mice with lethal C. albicans/S. aureus (i.e., coninfection resulted in >90% protection. The purpose of this study was to define requirements for C. dubliniensis/S. aureus-mediated protection and interrogate the mechanism of the protective response. Protection was conferred by C. dubliniensis alone or by killed C. dubliniensis plus live S. aureus. S. aureus alone was not protective, and killed S. aureus compromised C. dubliniensis-induced protection. C. dubliniensis/S. aureus also protected against lethal challenge by NAC plus S. aureus and could protect for a long-term duration (60 days between primary challenge and C. albicans/S. aureus rechallenge. Unexpectedly, mice deficient in T and B cells (Rag-1 knockouts [KO] survived both the initial C. dubliniensis/S. aureus challenge and the C. albicans/S. aureus rechallenge, indicating that adaptive immunity did not play a role. Similarly, mice depleted of macrophages prior to rechallenge were also protected. In contrast, protection was associated with high numbers of Gr-1hi polymorphonuclear leukocytes (PMNLs in peritoneal lavage fluid within 4 h of rechallenge, and in vivo depletion of Gr-1+ cells prior to rechallenge abrogated protection. These results suggest that Candida species can induce protection against a lethal C. albicans/S. aureus IAI that is mediated by PMNLs and postulated to be a unique form of

Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

NARCIS (Netherlands)

A.F. Brown (Aisling F.); A.G. Murphy (Alison G.); S.J. Lalor (Stephen J.); J.M. Leech (John M.); K.M. O’Keeffe (Kate M.); M. Mac Aogáin (Micheál); D.P. O’Halloran (Dara P.); K.A. Lacey (Keenan A.); M. Tavakol (Mehri); C.H. Hearnden (Claire H.); D. Fitzgerald-Hughes (Deirdre); H. Humphreys (Hilary); J.P. Fennell (Jérôme P.); W.J.B. van Wamel (Willem); T.J. Foster (Timothy J.); J.A. Geoghegan (Joan A.); E.C. Lavelle (Ed C.); T.R. Rogers (Thomas R.); R.M. McLoughlin (Rachel M.)

2015-01-01

textabstractMechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we

Hemagglutinating virus of Japan envelope (HVJ-E) can enhance the immune responses of swine immunized with killed PRRSV vaccine

Energy Technology Data Exchange (ETDEWEB)

Dai, Zhihong [State Key Laboratory of Agrobiotechnology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China); China Institute of Veterinary Drug Control, Beijing 100081 (China); Zhang, Quan [College of Veterinary Medicine, Yangzhou University, Yangzhou 225009 (China); Wang, Zaishi [China Institute of Veterinary Drug Control, Beijing 100081 (China); Zhang, Zhongqiu [State Key Laboratory of Agrobiotechnology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China); Veterinary Bureau, Ministry of Agriculture of the People' s Republic of China, Beijing 100125 (China); Guo, Pengju [Institute of Veterinary Medicine, Guangdong Academy of Agricultural Sciences, Guangdong 510640 (China); Zhao, Deming, E-mail: zhaodm@cau.edu.cn [State Key Laboratory of Agrobiotechnology, College of Veterinary Medicine, China Agricultural University, Beijing 100094 (China)

2011-11-11

Highlights: Black-Right-Pointing-Pointer We investigated the immunoadjuvant effects of HVJ-E on killed PRRSV vaccine. Black-Right-Pointing-Pointer HVJ-E enhanced the humoral and cellular responses of the piglets to PRRSV. Black-Right-Pointing-Pointer It is suggested that HVJ-E could be developed as a new-type adjuvant for mammals. -- Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically detrimental pig pathogen that causes significant losses for the pig industry. The immunostimulatory effects of hemagglutinating virus of Japan envelope (HVJ-E) in cancer therapy and the adjuvant efficacy of HVJ-E have been previously evaluated. The objective of this study was to investigate the adjuvant effects of HVJ-E on immunization with killed PRRSV vaccine, and to evaluate the protective effects of this immunization strategy against virulent PRRSV infection in piglets. Next, the PRRSV-specific antibody response, lymphocyte proliferation, PRRSV-specific IL-2, IL-10 and IFN-{gamma} production, and the overall protection efficacy were evaluated to assess the immune responses of the piglets. The results showed that the piglets inoculated simultaneously with killed PRRSV vaccine and HVJ-E had a significantly stronger immune response than those inoculated with killed PRRSV vaccine alone. Our results suggest that HVJ-E could be employed as an effective adjuvant to enhance the humoral and cellular responses of piglets to PRRSV.

Outer membrane vesicles of Gallibacterium anatis induce protective immunity in egg-laying hens.

Science.gov (United States)

Pors, Susanne E; Pedersen, Ida J; Skjerning, Ragnhild Bager; Thøfner, Ida C N; Persson, Gry; Bojesen, Anders M

2016-11-15

Gallibacterium anatis causes infections in the reproductive tract of egg-laying hens and induce increased mortality and decreased egg production. New prophylactic measures are needed in order to improve animal welfare and production efficiency. Bacterial outer membrane vesicles (OMVs) have previously shown promising results in protection against infections and we hypothesized that OMVs could serve as an immunogen to protect egg-laying hens against G. anatis. To investigate the immunogenic potential of G. anatis OMVs, two in vivo studies in egg-laying hens were made. The trials assessedthe degree of protection provided by immunization with G. anatis OMV against challenge and the IgY responses in serum after immunization and challenge, respectively. A total of 64 egg-laying hens were included in the trials. OMVs for immunization were produced and purified from a high-producing G. anatis ΔtolR mutant. Challenge was done with G. anatis 12656-12 and evaluated by scoring lesions and bacterial re-isolation rates from peritoneum. Finally, levels of OMV-specific IgY in sera were assayed by ELISA. Immunization with OMVs decreased the lesions scores significantly, while the bacterial re-isolation remained unchanged. Furthermore, a high OMV-specific IgY response was induced by immunization and subsequent challenge of the hens. The results strongly indicate that immunization with G. anatis OMVs provides significant protection against G. anatis challenge and induces specific antibody responses with high titers of OMV-specific IgY in serum. The results therefore show great promise for OMV based vaccines aiming at providing protecting against G. anatis in egg-laying hens. Copyright © 2016 Elsevier B.V. All rights reserved.

The serological response to heartwater immunization in cattle is an indicator of protective immunity

DEFF Research Database (Denmark)

Lawrence, J A; Tjørnehøj, Kirsten; Whiteland, A P

1995-01-01

A significant correlation was demonstrated in Friesian-cross steers between the serological response to previous vaccination with the Ball 3 strain of Cowdria ruminantium and the development of protective immunity against the Kalota isolate from Malawi. Of 10 animals which seroconverted after vac...

Insights into the mechanisms of protective immunity against Cryptococcus neoformans infection using a mouse model of pulmonary cryptococcosis.

Directory of Open Access Journals (Sweden)

Karen L Wozniak

2009-09-01

Full Text Available Cryptococcus neoformans is an opportunistic fungal pathogen that causes life-threatening pneumonia and meningoencephalitis in immune compromised individuals. Previous studies have shown that immunization of BALB/c mice with an IFN-gamma-producing C. neoformans strain, H99gamma, results in complete protection against a second pulmonary challenge with an otherwise lethal cryptococcal strain. The current study evaluated local anamnestic cell-mediated immune responses against pulmonary cryptococcosis in mice immunized with C. neoformans strain H99gamma compared to mice immunized with heat-killed C. neoformans (HKC.n.. Mice immunized with C. neoformans strain H99gamma had significantly reduced pulmonary fungal burden post-secondary challenge compared to mice immunized with HKC.n. Protection against pulmonary cryptococcosis was associated with increased pulmonary granulomatous formation and leukocyte infiltration followed by a rapid resolution of pulmonary inflammation, which protected the lungs from severe allergic bronchopulmonary mycosis (ABPM-pathology that developed in the lungs of mice immunized with HKC.n. Pulmonary challenge of interleukin (IL-4 receptor, IL-12p40, IL-12p35, IFN-gamma, T cell and B cell deficient mice with C. neoformans strain H99gamma demonstrated a requirement for Th1-type T cell-mediated immunity, but not B cell-mediated immunity, for the induction of H99gamma-mediated protective immune responses against pulmonary C. neoformans infection. CD4(+ T cells, CD11c(+ cells, and Gr-1(+ cells were increased in both proportion and absolute number in protected mice. In addition, significantly increased production of Th1-type/pro-inflammatory cytokines and chemokines, and conversely, reduced Th2-type cytokine production was observed in the lungs of protected mice. Interestingly, protection was not associated with increased production of cytokines IFN-gamma or TNF-alpha in lungs of protected mice. In conclusion, immunization with C

Preliminary Investigation of the Role of Cellular Immunity in Estrous Cycle Modulation of Post-Resection Breast Cancer Spread

National Research Council Canada - National Science Library

Hrushesky, William

2002-01-01

It is hypothesized that the short term objectives of doing this proposal are to better understand which sex steroids and which cellular immune functions control post resection metastatic cancer spread...

Humoral and cellular immune responses to synthetic peptides of the Leishmania donovani kinetoplastid membrane protein-11

DEFF Research Database (Denmark)

Jensen, A T; Gasim, S; Ismail, A

1998-01-01

as solid-phase ligands in enzyme-linked immunosorbent assays (ELISAs) and as stimulating antigens in lymphoproliferative assays in order to evaluate humoral and cellular immune responses to well-defined sequences of the protein. Antibody reactivity against the three peptides was measured in plasma from 63...

Anterior Chamber-Associated Immune Deviation (ACAID: An Acute Response to Ocular Insult Protects from Future Immune-Mediated Damage?

Directory of Open Access Journals (Sweden)

Robert E. Cone

2009-01-01

Full Text Available The “immune privilege” that inhibits immune defense mechanisms that could lead to damage to sensitive ocular tissue is based on the expression of immunosuppressive factors on ocular tissue and in ocular fluids. In addition to this environmental protection, the injection of antigen into the anterior chamber or infection in the anterior chamber induces a systemic suppression of potentially damaging cell-mediated and humoral responses to the antigen. Here we discuss evidence that suggests that Anterior Chamber-Associated Immune Deviation (ACAID a is initiated by an ocular response to moderate inflammation that leads to a systemic immunoregulatory response. Injection into the anterior chamber induces a rise in TNF-α and MCP-1 in aqueous humor and an infiltration of circulating F4/80 + monocytes that home to the iris. The induction of ACAID is dependent on this infiltration of circulating monocytes that eventually emigrate to the thymus and spleen where they induce regulatory T cells that inhibit the inductive or effector phases of a cell-mediated immune response. ACAID therefore protects the eye from the collateral damage of an immune response to infection by suppressing a future potentially damaging response to infection.

Pseudomonas aeruginosa RhlR is required to neutralize the cellular immune response in a Drosophila melanogaster oral infection model

Science.gov (United States)

Limmer, Stefanie; Haller, Samantha; Drenkard, Eliana; Lee, Janice; Yu, Shen; Kocks, Christine; Ausubel, Frederick M.; Ferrandon, Dominique

2011-01-01

An in-depth mechanistic understanding of microbial infection necessitates a molecular dissection of host–pathogen relationships. Both Drosophila melanogaster and Pseudomonas aeruginosa have been intensively studied. Here, we analyze the infection of D. melanogaster by P. aeruginosa by using mutants in both host and pathogen. We show that orally ingested P. aeruginosa crosses the intestinal barrier and then proliferates in the hemolymph, thereby causing the infected flies to die of bacteremia. Host defenses against ingested P. aeruginosa included an immune deficiency (IMD) response in the intestinal epithelium, systemic Toll and IMD pathway responses, and a cellular immune response controlling bacteria in the hemocoel. Although the observed cellular and intestinal immune responses appeared to act throughout the course of the infection, there was a late onset of the systemic IMD and Toll responses. In this oral infection model, P. aeruginosa PA14 did not require its type III secretion system or other well-studied virulence factors such as the two-component response regulator GacA or the protease AprA for virulence. In contrast, the quorum-sensing transcription factor RhlR, but surprisingly not LasR, played a key role in counteracting the cellular immune response against PA14, possibly at an early stage when only a few bacteria are present in the hemocoel. These results illustrate the power of studying infection from the dual perspective of host and pathogen by revealing that RhlR plays a more complex role during pathogenesis than previously appreciated. PMID:21987808

Immunization with a DNA vaccine encoding Toxoplasma gondii Superoxide dismutase (TgSOD) induces partial immune protection against acute toxoplasmosis in BALB/c mice.

Science.gov (United States)

Liu, Yuan; Cao, Aiping; Li, Yawen; Li, Xun; Cong, Hua; He, Shenyi; Zhou, Huaiyu

2017-06-07

Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects all warm-blooded animals including humans and causes toxoplasmosis. An effective vaccine could be an ideal choice for preventing and controlling toxoplasmosis. T. gondii Superoxide dismutase (TgSOD) might participate in affecting the intracellular growth of both bradyzoite and tachyzoite forms. In the present study, the TgSOD gene was used to construct a DNA vaccine (pEGFP-SOD). TgSOD gene was amplified and inserted into eukaryotic vector pEGFP-C1 and formed the DNA vaccine pEGFP-SOD. Then the BALB/c mice were immunized intramuscularly with the DNA vaccine and those injected with pEGFP-C1, PBS or nothing were treated as controls. Four weeks after the last immunization, all mouse groups followed by challenging intraperitoneally with tachyzoites of T. gondii ME49 strain. Results showed higher levels of total IgG, IgG2α in the sera and interferon gamma (IFN-γ) in the splenocytes from pEGFP-SOD inoculated mice than those unvaccinated, or inoculated with either empty plasmid vector or PBS. The proportions of CD4 + T cells and CD8 + T cells in the spleen from pEGFP-SOD inoculated mice were significantly (p < 0.05) increased compared to control groups. In addition, the survival time of mice immunized with pEGFP-SOD was significantly prolonged as compared to the controls (p < 0.05) although all the mice died. The present study revealed that the DNA vaccine triggered strong humoral and cellular immune responses, and aroused partial protective immunity against acute T. gondii infection in BALB/c mice. The collective data suggests the SOD may be a potential vaccine candidate for further development.

Innate immune reconstitution with suppression of HIV-1.

Science.gov (United States)

Scully, Eileen P; Lockhart, Ainsley; Garcia-Beltran, Wilfredo; Palmer, Christine D; Musante, Chelsey; Rosenberg, Eric; Allen, Todd M; Chang, J Judy; Bosch, Ronald J; Altfeld, Marcus

2016-03-17

Progressive HIV-1 infection leads to both profound immune suppression and pathologic inflammation in the majority of infected individuals. While adaptive immune dysfunction, as evidenced by CD4 + T cell depletion and exhaustion, has been extensively studied, less is known about the functional capacity of innate immune cell populations in the context of HIV-1 infection. Given the broad susceptibility to opportunistic infections and the dysregulated inflammation observed in progressive disease, we hypothesized that there would be significant changes in the innate cellular responses. Using a cohort of patients with multiple samplings before and after antiretroviral therapy (ART) initiation, we demonstrated increased responses to innate immune stimuli following viral suppression, as measured by the production of inflammatory cytokines. Plasma viral load itself had the strongest association with this change in innate functional capacity. We further identified epigenetic modifications in the TNFA promoter locus in monocytes that are associated with viremia, suggesting a molecular mechanism for the observed changes in innate immune function following initiation of ART. These data indicate that suppression of HIV-1 viremia is associated with changes in innate cellular function that may in part determine the restoration of protective immune responses.

Different Candida parapsilosis clinical isolates and lipase deficient strain trigger an altered cellular immune response

Directory of Open Access Journals (Sweden)

Renata eToth

2015-10-01

Full Text Available Numerous human diseases can be associated with fungal infections either as potential causative agents or as a result of changed immune status due to a primary disease. Fungal infections caused by Candida species can vary from mild to severe dependent upon the site of infection, length of exposure and past medical history. Patients with impaired immune status are at increased risk for chronic fungal infections. Recent epidemiologic studies have revealed the increasing incidence of candidiasis caused by non-albicans species such as C. parapsilosis. Due to its increasing relevance we chose two distinct C. parapsilosis strains, to describe the cellular innate immune response towards this species. In the first section of our study we compared the interaction of CLIB 214 and GA1 cells with murine and human macrophages. Both strains are commonly used to investigate C. parapsilosis virulence properties. CLIB 214 is a rapidly pseudohyphae-forming strain and GA1 is an isolate that mainly exists in a yeast form. Our results showed, that the phagocyte response was similar in terms of overall uptake, however differences were observed in macrophage migration and engulfment of fungal cells. As C. parapsilosis releases extracellular lipases in order to promote host invasion we further investigated the role of these secreted components during the distinct stages of the phagocytic process. Using a secreted lipase deficient mutant strain and the parental strain GA1 individually and simultaneously, we confirmed that fungal secreted lipases influence the fungi’s virulence by detecting altered innate cellular responses.In this study we report that two isolates of a single species can trigger markedly distinct host responses and that lipase secretion plays a role on the cellular level of host pathogen interactions.

Characterization of cellular immune response and innate immune signaling in human and nonhuman primate primary mononuclear cells exposed to Burkholderia mallei.

Science.gov (United States)

Alam, Shahabuddin; Amemiya, Kei; Bernhards, Robert C; Ulrich, Robert G; Waag, David M; Saikh, Kamal U

2015-01-01

Burkholderia pseudomallei infection causes melioidosis and is often characterized by severe sepsis. Although rare in humans, Burkholderia mallei has caused infections in laboratory workers, and the early innate cellular response to B. mallei in human and nonhuman primates has not been characterized. In this study, we examined the primary cellular immune response to B. mallei in PBMC cultures of non-human primates (NHPs), Chlorocebus aethiops (African Green Monkeys), Macaca fascicularis (Cynomolgus macaque), and Macaca mulatta (Rhesus macaque) and humans. Our results demonstrated that B. mallei elicited strong primary pro-inflammatory cytokines (IFN-γ, TNF-α, IL-1β, and IL-6) equivalent to the levels of B. pseudomallei in primary PBMC cultures of NHPs and humans. When we examined IL-1β and other cytokine responses by comparison to Escherichia coli LPS, African Green Monkeys appears to be most responsive to B. mallei than Cynomolgus or Rhesus. Characterization of the immune signaling mechanism for cellular response was conducted by using a ligand induced cell-based reporter assay, and our results demonstrated that MyD88 mediated signaling contributed to the B. mallei and B. pseudomallei induced pro-inflammatory responses. Notably, the induced reporter activity with B. mallei, B. pseudomallei, or purified LPS from these pathogens was inhibited and cytokine production was attenuated by a MyD88 inhibitor. Together, these results show that in the scenario of severe hyper-inflammatory responses to B. mallei infection, MyD88 targeted therapeutic intervention may be a successful strategy for therapy. Published by Elsevier Ltd.

Altered Cellular Metabolism Drives Trained Immunity.

Science.gov (United States)

Sohrabi, Yahya; Godfrey, Rinesh; Findeisen, Hannes M

2018-04-04

Exposing innate immune cells to an initial insult induces a long-term proinflammatory response due to metabolic and epigenetic alterations which encompass an emerging new concept called trained immunity. Recent studies provide novel insights into mechanisms centered on metabolic reprogramming which induce innate immune memory in hematopoietic stem cells and monocytes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Protective effects of melatonin against irradiation: an in vitro study to assess immune damages in blood and bone marrow lymphocytes of animal cells

International Nuclear Information System (INIS)

Rai, Seema

2013-01-01

Human health can be adversely affected by exposure to radiation. This can come in the form of simple sunlight, to X-ray exposure. Recently there is a great increase in the number of personnel working with ionizing radiations, together with the development of nuclear weapon. Tissue damage, whether resulting in a sunburn or in thyroid cancer etc. is caused by 'ionizing' radiation. Further, Local acute reaction to radiation exposure during 'radiation therapy' is more frequent than whole body radiation which interferes with the cellular activity (mostly proliferative cells such as skin, blood, cancer, digestive tract cells) and leads to the suppression of immune system function. 1) It penetrates the cells and tissue and can produce severe damage to the required/pathogenic cells. 2) Indirect actions are (free radical generation, destruction of receptor sites etc.) still not known. 3) Severe immune dysfunction after several doses of radiation is a common factor. What does the term mean? It describes the release of free radicals from the molecules struck by the radiation. Raising glutathione levels protects cells from damage by the most dangerous of free radicals (the hydroxyl-radical) released when ionizing radiation hits us. Therefore, in search of a protective measurement to reduce the hazardous effects of radiation on immune system we propose an approach to reduce the damages caused by ion radiation to immune cells by using melatonin which has been established as a strong antioxidant and immune-modulator. (author)

An experimental protocol for the establishment of dogs with long-term cellular immune reactions to Leishmania antigens

Directory of Open Access Journals (Sweden)

Márcia Cristina Aquino Teixeira

2011-03-01

Full Text Available Domestic dogs are considered to be the main reservoirs of zoonotic visceral leishmaniasis. In this work, we evaluated a protocol to induce Leishmania infantum/Leishmania chagasi-specific cellular and humoral immune responses in dogs, which consisted of two injections of Leishmania promastigote lysate followed by a subcutaneous inoculation of viable promastigotes. The primary objective was to establish a canine experimental model to provide positive controls for testing immune responses to Leishmania in laboratory conditions. After inoculation of viable promastigotes, specific proliferative responses of peripheral blood mononuclear cells (PBMCs to either Leishmania lysate or recombinant proteins, the in vitro production of interferon-γ by antigen-stimulated PBMCs and a significant increase in circulating levels of anti-Leishmania antibodies were observed. The immunized dogs also displayed positive delayed-type hypersensitivity reactions to Leishmania crude antigens and to purified recombinant proteins. An important finding that supports the suitability of the dogs as positive controls is that they remained healthy for the entire observation period, i.e., more than seven years after infection. Following the Leishmania antigen lysate injections, the infection of dogs by the subcutaneous route appears to induce a sustained cellular immune response, leading to an asymptomatic infection. This provides a useful model for both the selection of immunogenic Leishmania antigens and for immunobiological studies on their possible immunoprotective activities.

Unique aspects of the perinatal immune system.

Science.gov (United States)

Zhang, Xiaoming; Zhivaki, Dania; Lo-Man, Richard

2017-08-01

The early stages of life are associated with increased susceptibility to infection, which is in part due to an ineffective immune system. In the context of infection, the immune system must be stimulated to provide efficient protection while avoiding insufficient or excessive activation. Yet, in early life, age-dependent immune regulation at molecular and cellular levels contributes to a reduced immunological fitness in terms of pathogen clearance and response to vaccines. To enable microbial colonization to be tolerated at birth, epigenetic immune cell programming and early life-specific immune regulatory and effector mechanisms ensure that vital functions and organ development are supported and that tissue damage is avoided. Advancement in our understanding of age-related remodelling of immune networks and the consequent tuning of immune responsiveness will open up new possibilities for immune intervention and vaccine strategies that are designed specifically for early life.

A systems biology approach reveals that tissue tropism to West Nile virus is regulated by antiviral genes and innate immune cellular processes.

Directory of Open Access Journals (Sweden)

Mehul S Suthar

2013-02-01

Full Text Available The actions of the RIG-I like receptor (RLR and type I interferon (IFN signaling pathways are essential for a protective innate immune response against the emerging flavivirus West Nile virus (WNV. In mice lacking RLR or IFN signaling pathways, WNV exhibits enhanced tissue tropism, indicating that specific host factors of innate immune defense restrict WNV infection and dissemination in peripheral tissues. However, the immune mechanisms by which the RLR and IFN pathways coordinate and function to impart restriction of WNV infection are not well defined. Using a systems biology approach, we defined the host innate immune response signature and actions that restrict WNV tissue tropism. Transcriptional profiling and pathway modeling to compare WNV-infected permissive (spleen and nonpermissive (liver tissues showed high enrichment for inflammatory responses, including pattern recognition receptors and IFN signaling pathways, that define restriction of WNV replication in the liver. Assessment of infected livers from Mavs(-/- × Ifnar(-/- mice revealed the loss of expression of several key components within the natural killer (NK cell signaling pathway, including genes associated with NK cell activation, inflammatory cytokine production, and NK cell receptor signaling. In vivo analysis of hepatic immune cell infiltrates from WT mice demonstrated that WNV infection leads to an increase in NK cell numbers with enhanced proliferation, maturation, and effector action. In contrast, livers from Mavs(-/- × Ifnar(-/- infected mice displayed reduced immune cell infiltration, including a significant reduction in NK cell numbers. Analysis of cocultures of dendritic and NK cells revealed both cell-intrinsic and -extrinsic roles for the RLR and IFN signaling pathways to regulate NK cell effector activity. Taken together, these observations reveal a complex innate immune signaling network, regulated by the RLR and IFN signaling pathways, that drives tissue

A change in inflammatory footprint precedes plaque instability: a systematic evaluation of cellular aspects of the adaptive immune response in human atherosclerosis

NARCIS (Netherlands)

van Dijk, R. A.; Duinisveld, A. J. F.; Schaapherder, A. F.; Mulder-Stapel, A.; Hamming, J. F.; Kuiper, J.; de Boer, O. J.; van der Wal, A. C.; Kolodgie, F. D.; Virmani, R.; Lindeman, J. H. N.

2015-01-01

Experimental studies characterize adaptive immune response as a critical factor in the progression and complications of atherosclerosis. Yet, it is unclear whether these observations translate to the human situation. This study systematically evaluates cellular components of the adaptive immune

Alphavirus Replicon DNA Vectors Expressing Ebola GP and VP40 Antigens Induce Humoral and Cellular Immune Responses in Mice

Directory of Open Access Journals (Sweden)

Shoufeng Ren

2018-01-01

Full Text Available Ebola virus (EBOV causes severe hemorrhagic fevers in humans, and no approved therapeutics or vaccine is currently available. Glycoprotein (GP is the major protective antigen of EBOV, and can generate virus-like particles (VLPs by co-expression with matrix protein (VP40. In this study, we constructed a recombinant Alphavirus Semliki Forest virus (SFV replicon vector DREP to express EBOV GP and matrix viral protein (VP40. EBOV VLPs were successfully generated and achieved budding from 293 cells after co-transfection with DREP-based GP and VP40 vectors (DREP-GP+DREP-VP40. Vaccination of BALB/c mice with DREP-GP, DREP-VP40, or DREP-GP+DREP-VP40 vectors, followed by immediate electroporation resulted in a mixed IgG subclass production, which recognized EBOV GP and/or VP40 proteins. This vaccination regimen also led to the generation of both Th1 and Th2 cellular immune responses in mice. Notably, vaccination with DREP-GP and DREP-VP40, which produces both GP and VP40 antigens, induced a significantly higher level of anti-GP IgG2a antibody and increased IFN-γ secreting CD8+ T-cell responses relative to vaccination with DREP-GP or DREP-VP40 vector alone. Our study indicates that co-expression of GP and VP40 antigens based on the SFV replicon vector generates EBOV VLPs in vitro, and vaccination with recombinant DREP vectors containing GP and VP40 antigens induces Ebola antigen-specific humoral and cellular immune responses in mice. This novel approach provides a simple and efficient vaccine platform for Ebola disease prevention.

Protective immune responses during prepatency in goat kids experimentally infected with Eimeria ninakohlyakimovae.

Science.gov (United States)

Matos, L; Muñoz, M C; Molina, J M; Rodríguez, F; Perez, D; Lopez, A; Ferrer, O; Hermosilla, C; Taubert, A; Ruiz, A

2017-08-15

group compared to the challenged control animals. Furthermore, in the challenged E. ninakohlyakimovae-infected animals a significantly higher number of mucosal CD4 + and CD8 + lymphocytes were observed, indicating that these T cell subpopulations might be involved in protective host immune response elicited against early stages of parasite development. The immune response was however very complex, as antigen presenting cells and other effector cell populations of the innate immune system, as well as certain cytokines, were involved. In summary, the results of this study contribute to the better understanding of local cellular and humoral immune responses against caprine E. ninakohlyakimovae, particularly during the prepatency. Copyright © 2017 Elsevier B.V. All rights reserved.

Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

Science.gov (United States)

Lalor, Stephen J.; Leech, John M.; O’Keeffe, Kate M.; Mac Aogáin, Micheál; O’Halloran, Dara P.; Lacey, Keenan A.; Tavakol, Mehri; Hearnden, Claire H.; Fitzgerald-Hughes, Deirdre; Humphreys, Hilary; Fennell, Jérôme P.; van Wamel, Willem J.; Foster, Timothy J.; Geoghegan, Joan A.; Lavelle, Ed C.; Rogers, Thomas R.; McLoughlin, Rachel M.

2015-01-01

Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans. PMID:26539822

Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

LENUS (Irish Health Repository)

Brown, Aisling F

2015-01-01

Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans.

Serratia marcescens Suppresses Host Cellular Immunity via the Production of an Adhesion-inhibitory Factor against Immunosurveillance Cells*

Science.gov (United States)

Ishii, Kenichi; Adachi, Tatsuo; Hamamoto, Hiroshi; Sekimizu, Kazuhisa

2014-01-01

Injection of a culture supernatant of Serratia marcescens into the bloodstream of the silkworm Bombyx mori increased the number of freely circulating immunosurveillance cells (hemocytes). Using a bioassay with live silkworms, serralysin metalloprotease was purified from the culture supernatant and identified as the factor responsible for this activity. Serralysin inhibited the in vitro attachment of both silkworm hemocytes and murine peritoneal macrophages. Incubation of silkworm hemocytes or murine macrophages with serralysin resulted in degradation of the cellular immune factor BmSPH-1 or calreticulin, respectively. Furthermore, serralysin suppressed in vitro phagocytosis of bacteria by hemocytes and in vivo bacterial clearance in silkworms. Disruption of the ser gene in S. marcescens attenuated its host killing ability in silkworms and mice. These findings suggest that serralysin metalloprotease secreted by S. marcescens suppresses cellular immunity by decreasing the adhesive properties of immunosurveillance cells, thereby contributing to bacterial pathogenesis. PMID:24398686

Serratia marcescens suppresses host cellular immunity via the production of an adhesion-inhibitory factor against immunosurveillance cells.

Science.gov (United States)

Ishii, Kenichi; Adachi, Tatsuo; Hamamoto, Hiroshi; Sekimizu, Kazuhisa

2014-02-28

Injection of a culture supernatant of Serratia marcescens into the bloodstream of the silkworm Bombyx mori increased the number of freely circulating immunosurveillance cells (hemocytes). Using a bioassay with live silkworms, serralysin metalloprotease was purified from the culture supernatant and identified as the factor responsible for this activity. Serralysin inhibited the in vitro attachment of both silkworm hemocytes and murine peritoneal macrophages. Incubation of silkworm hemocytes or murine macrophages with serralysin resulted in degradation of the cellular immune factor BmSPH-1 or calreticulin, respectively. Furthermore, serralysin suppressed in vitro phagocytosis of bacteria by hemocytes and in vivo bacterial clearance in silkworms. Disruption of the ser gene in S. marcescens attenuated its host killing ability in silkworms and mice. These findings suggest that serralysin metalloprotease secreted by S. marcescens suppresses cellular immunity by decreasing the adhesive properties of immunosurveillance cells, thereby contributing to bacterial pathogenesis.

Local Th17/IgA immunity correlate with protection against intranasal infection with Streptococcus pyogenes.

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Rasmus Mortensen

Full Text Available Streptococcus pyogenes (group A streptococcus, GAS is responsible for a wide array of infections. Respiratory transmission via droplets is the most common mode of transmission but it may also infect the host via other routes such as lesions in the skin. To advance the development of a future vaccine against GAS, it is therefore important to investigate how protective immunity is related to the route of vaccine administration. To explore this, we examined whether a parenterally administered anti-GAS vaccine could protect against an intranasal GAS infection or if this would require locally primed immunity. We foundd that a parenteral CAF01 adjuvanted GAS vaccine offered no protection against intranasal infection despite inducing strong systemic Th1/Th17/IgG immunity that efficiently protected against an intraperitoneal GAS infection. However, the same vaccine administered via the intranasal route was able to induce protection against repeated intranasal GAS infections in a murine challenge model. The lack of intranasal protection induced by the parenteral vaccine correlated with a reduced mucosal recall response at the site of infection. Taken together, our results demonstrate that locally primed immunity is important for the defense against intranasal infection with Streptococcus pyogenes.

Perturbation of gut bacteria induces a coordinated cellular immune response in the purple sea urchin larva

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CH Ho, Eric; Buckley, Katherine M; Schrankel, Catherine S; Schuh, Nicholas W; Hibino, Taku; Solek, Cynthia M; Bae, Koeun; Wang, Guizhi; Rast, Jonathan P

2016-01-01

The purple sea urchin (Strongylocentrotus purpuratus) genome sequence contains a complex repertoire of genes encoding innate immune recognition proteins and homologs of important vertebrate immune regulatory factors. To characterize how this immune system is deployed within an experimentally tractable, intact animal, we investigate the immune capability of the larval stage. Sea urchin embryos and larvae are morphologically simple and transparent, providing an organism-wide model to view immune response at cellular resolution. Here we present evidence for immune function in five mesenchymal cell types based on morphology, behavior and gene expression. Two cell types are phagocytic; the others interact at sites of microbial detection or injury. We characterize immune-associated gene markers for three cell types, including a perforin-like molecule, a scavenger receptor, a complement-like thioester-containing protein and the echinoderm-specific immune response factor 185/333. We elicit larval immune responses by (1) bacterial injection into the blastocoel and (2) seawater exposure to the marine bacterium Vibrio diazotrophicus to perturb immune state in the gut. Exposure at the epithelium induces a strong response in which pigment cells (one type of immune cell) migrate from the ectoderm to interact with the gut epithelium. Bacteria that accumulate in the gut later invade the blastocoel, where they are cleared by phagocytic and granular immune cells. The complexity of this coordinated, dynamic inflammatory program within the simple larval morphology provides a system in which to characterize processes that direct both aspects of the echinoderm-specific immune response as well as those that are shared with other deuterostomes, including vertebrates. PMID:27192936

Immune correlates of protection for dengue: State of the art and research agenda.

Science.gov (United States)

Katzelnick, Leah C; Harris, Eva

2017-08-24

Dengue viruses (DENV1-4) are mosquito-borne flaviviruses estimated to cause up to ∼400 million infections and ∼100 million dengue cases each year. Factors that contribute to protection from and risk of dengue and severe dengue disease have been studied extensively but are still not fully understood. Results from Phase 3 vaccine efficacy trials have recently become available for one vaccine candidate, now licensed for use in several countries, and more Phase 2 and 3 studies of additional vaccine candidates are ongoing, making these issues all the more urgent and timely. At the "Summit on Dengue Immune Correlates of Protection", held in Annecy, France, on March 8-9, 2016, dengue experts from diverse fields came together to discuss the current understanding of the immune response to and protection from DENV infection and disease, identify key unanswered questions, discuss data on immune correlates and plans for comparison of results across assays/consortia, and propose a research agenda for investigation of dengue immune correlates, all in the context of both natural infection studies and vaccine trials. Copyright © 2017.

The HyVac4 subunit vaccine efficiently boosts BCG-primed anti-mycobacterial protective immunity.

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Rolf Billeskov

Full Text Available BACKGROUND: The current vaccine against tuberculosis (TB, BCG, has failed to control TB worldwide and the protective efficacy is moreover limited to 10-15 years. A vaccine that could efficiently boost a BCG-induced immune response and thus prolong protective immunity would therefore have a significant impact on the global TB-burden. METHODS/FINDINGS: In the present study we show that the fusion protein HyVac4 (H4, consisting of the mycobacterial antigens Ag85B and TB10.4, given in the adjuvant IC31® or DDA/MPL effectively boosted and prolonged immunity induced by BCG, leading to improved protection against infection with virulent M. tuberculosis (M.tb. Increased protection correlated with an increased percentage of TB10.4 specific IFNγ/TNFα/IL-2 or TNFα/IL-2 producing CD4 T cells at the site of infection. Moreover, this vaccine strategy did not compromise the use of ESAT-6 as an accurate correlate of disease development/vaccine efficacy. Indeed both CD4 and CD8 ESAT-6 specific T cells showed significant correlation with bacterial levels. CONCLUSIONS/SIGNIFICANCE: H4-IC31® can efficiently boost BCG-primed immunity leading to an increased protective anti-M.tb immune response dominated by IFNγ/TNFα/IL-2 or TNFα/IL2 producing CD4 T cells. H4 in the CD4 T cell inducing adjuvant IC31® is presently in clinical trials.

Immunization of baboons with attenuated schistosomula of Schistosoma haematobium: levels of protection induced by immunization with larvae irradiated with 20 and 60 krad

International Nuclear Information System (INIS)

Harrison, R.A.; Bickle, Q.D.; Sturrock, R.F.; Taylor, M.G.; Webbe, G.; Kiare, S.; James, E.R.; Andrews, B.J.

1990-01-01

The authors have demonstrated that baboons can be immunized with S. haemotobium schistosomula irradiated with 20 krad in a regimen that induces 90% protection. While this high level of protection has stimulated a discussion on the feasibility of a human volunteer trial (Von Lichtenberg, 1985), results of further studies particularly on (i) the pathogensis of immunization per se (Byram et al., 1989), (ii) the longevity of protection, and (iii) the protective efficacy of cryopreserved irradiated S. haemotobium schistosomula (R. Harrison et al., in preparation), prevent recommending this form of vaccination for human application. (author)

Insecticidal activity of the metalloprotease AprA occurs through suppression of host cellular and humoral immunity.

Science.gov (United States)

Lee, Seung Ah; Jang, Seong Han; Kim, Byung Hyun; Shibata, Toshio; Yoo, Jinwook; Jung, Yunjin; Kawabata, Shun-Ichiro; Lee, Bok Luel

2018-04-01

The biochemical characterization of virulence factors from entomopathogenic bacteria is important to understand entomopathogen-insect molecular interactions. Pseudomonas entomophila is a typical entomopathogenic bacterium that harbors virulence factors against several insects. However, the molecular actions of these factors against host innate immune responses are not clearly elucidated. In this study, we observed that bean bugs (Riptortus pedestris) that were injected with P. entomophila were highly susceptible to this bacterium. To determine how P. entomophila counteracts the host innate immunity to survive within the insect, we purified a highly enriched protein with potential host insect-killing activity from the culture supernatant of P. entomophila. Then, a 45-kDa protein was purified to homogeneity and identified as AprA which is an alkaline zinc metalloprotease of the genus Pseudomonas by liquid chromatography mass spectrometry (LC-MS). Purified AprA showed a pronounced killing effect against host insects and suppressed both host cellular and humoral innate immunity. Furthermore, to show that AprA is an important insecticidal protein of P. entomophila, we used an aprA-deficient P. entomophila mutant strain (ΔaprA). When ΔaprA mutant cells were injected to host insects, this mutant exhibited extremely attenuated virulence. In addition, the cytotoxicity against host hemocytes and the antimicrobial peptide-degrading ability of the ΔaprA mutant were greatly decreased. These findings suggest that AprA functions as an important insecticidal protein of P. entomophila via suppression of host cellular and humoral innate immune responses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Immunization with cholera toxin B subunit induces high-level protection in the suckling mouse model of cholera.

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Gregory A Price

Full Text Available Cholera toxin (CT is the primary virulence factor responsible for severe cholera. Vibrio cholerae strains unable to produce CT show severe attenuation of virulence in animals and humans. The pentameric B subunit of CT (CTB contains the immunodominant epitopes recognized by antibodies that neutralize CT. Although CTB is a potent immunogen and a promising protective vaccine antigen in animal models, immunization of humans with detoxified CT failed to protect against cholera. We recently demonstrated however that pups reared from mice immunized intraperitoneally (IP with 3 doses of recombinant CTB were well protected against a highly lethal challenge dose of V. cholerae N16961. The present study investigated how the route and number of immunizations with CTB could influence protective efficacy in the suckling mouse model of cholera. To this end female mice were immunized with CTB intranasally (IN, IP, and subcutaneously (SC. Serum and fecal extracts were analyzed for anti-CTB antibodies by quantitative ELISA, and pups born to immunized mothers were challenged orogastrically with a lethal dose of V. cholerae. Pups from all immunized groups were highly protected from death by 48 hours (64-100% survival. Cox regression showed that percent body weight loss at 24 hours predicted death by 48 hours, but we were unable to validate a specific amount of weight loss as a surrogate marker for protection. Although CTB was highly protective in all regimens, three parenteral immunizations showed trends toward higher survival and less weight loss at 24 hours post infection. These results demonstrate that immunization with CTB by any of several routes and dosing regimens can provide protection against live V. cholerae challenge in the suckling mouse model of cholera. Our data extend the results of previous studies and provide additional support for the inclusion of CTB in the development of a subunit vaccine against V. cholerae.

Radioresistance of immunized animals in internal irradiation

International Nuclear Information System (INIS)

Kal'nitskij, S.A.; Ponomareva, T.V.; Shubik, V.M.

1981-01-01

The influence of an immunization with bacterial vaccines and antimeasles-gamma-globulin on the radioresistance of raceless white mice was studied. In the vaccinated animals a higher survival rate and duration of life, a better general condition and a better curve of weight and stronger physical stamina were stated compared to the merely irradiated mice. The higher radioresistance is ascribed to the stimulation of cellular and humoral factors of the unspecific protection against infection, to the repair of the lymphoid tissue of the immunized animals and to the decrease in autosensibilization. (author)

Continuous DC-CIK infusions restore CD8+ cellular immunity, physical activity and improve clinical efficacy in advanced cancer patients unresponsive to conventional treatments.

Science.gov (United States)

Zhao, Yan-Jie; Jiang, Ni; Song, Qing-Kun; Wu, Jiang-Ping; Song, Yu-Guang; Zhang, Hong-Mei; Chen, Feng; Zhou, Lei; Wang, Xiao-Li; Zhou, Xin-Na; Yang, Hua-Bing; Ren, Jun; Lyerly, Herbert Kim

2015-01-01

There are few choices for treatment of advanced cancer patients who do not respond to or tolerate conventional anti-cancer treatments. Therefore this study aimed to deploy the benefits and clinical efficacy of continuous dendritic cell-cytokine induced killer cell infusions in such patients. A total of 381 infusions (from 67 advanced cases recruited) were included in this study. All patients underwent peripheral blood mononuclear cell apheresis for the following cellular therapy and dendritic cells-cytokine induced killer cells were expanded in vitro. Peripheral blood T lymphocyte subsets were quantified through flow cytometry to address the cellular immunity status. Clinical efficacy and physical activities were evaluated by RECIST criteria and Eastern Cooperative Oncology Group scores respectively. Logistic regression model was used to estimate the association between cellular infusions and clinical benefits. An average of 5.7±2.94x10(9) induced cells were infused each time and patients were exposed to 6 infusions. Cellular immunity was improved in that cytotoxic CD8+CD28+T lymphocytes were increased by 74% and suppressive CD8+CD28-T lymphocytes were elevated by 16% (p<0.05). Continuous infusion of dendritic cells-cytokine induced killer cells was associated with improvement of both patient status and cellular immunity. A median of six infusions were capable of reducing risk of progression by 70% (95%CI 0.10-0.91). Every elevation of one ECOG score corresponded to a 3.90-fold higher progression risk (p<0.05) and 1% increase of CD8+CD28- T cell proportion reflecting a 5% higher risk of progression (p<0.05). In advanced cancer patients, continuous dendritic cell-cytokine induced killer cell infusions are capable of recovering cellular immunity, improving patient status and quality of life in those who are unresponsive to conventional cancer treatment.

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens.

Science.gov (United States)

da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J; von Messling, Veronika

2017-04-15

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near-wild-type titers, and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone-inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment protein- and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were immunized with only a RABV expressing the attachment protein of CDV vaccine strain Onderstepoort succumbed to infection with a more recent wild-type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains. IMPORTANCE Rabies virus and canine distemper virus (CDV) cause high mortality rates and death in many carnivores. While rabies vaccines are inactivated and thus have an excellent safety profile and high stability, live-attenuated CDV vaccines can retain residual virulence in highly susceptible species. Here we generated recombinant inactivated rabies viruses that carry one of the CDV glycoproteins on their surface. Ferrets immunized twice with a mix of recombinant rabies viruses carrying the CDV fusion and attachment glycoproteins were protected from lethal CDV challenge, whereas all animals that received

MF59- and Al(OH3-adjuvanted Staphylococcus aureus (4C-Staph vaccines induce sustained protective humoral and cellular immune responses, with a critical role for effector CD4 T cells at low antibody titers.

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Elisabetta eMonaci

2015-09-01

Full Text Available Staphylococcus aureus (S. aureus is an important opportunistic pathogen that may cause invasive life-threatening infections like sepsis and pneumonia. Due to increasing antibiotic-resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell deficient mice, we demonstrated that both T and B cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen.

Plasmid DNA loaded chitosan nanoparticles for nasal mucosal immunization against hepatitis B.

Science.gov (United States)

Khatri, Kapil; Goyal, Amit K; Gupta, Prem N; Mishra, Neeraj; Vyas, Suresh P

2008-04-16

This work investigates the preparation and in vivo efficacy of plasmid DNA loaded chitosan nanoparticles for nasal mucosal immunization against hepatitis B. Chitosan pDNA nanoparticles were prepared using a complex coacervation process. Prepared nanoparticles were characterized for size, shape, surface charge, plasmid loading and ability of nanoparticles to protect DNA against nuclease digestion and for their transfection efficacy. Nasal administration of nanoparticles resulted in serum anti-HBsAg titre that was less compared to that elicited by naked DNA and alum adsorbed HBsAg, but the mice were seroprotective within 2 weeks and the immunoglobulin level was above the clinically protective level. However, intramuscular administration of naked DNA and alum adsorbed HBsAg did not elicit sIgA titre in mucosal secretions that was induced by nasal immunization with chitosan nanoparticles. Similarly, cellular responses (cytokine levels) were poor in case of alum adsorbed HBsAg. Chitosan nanoparticles thus produced humoral (both systemic and mucosal) and cellular immune responses upon nasal administration. The study signifies the potential of chitosan nanoparticles as DNA vaccine carrier and adjuvant for effective immunization through non-invasive nasal route.

Co-administration of plasmid expressing IL-12 with 14-kDa Schistosoma mansoni fatty acid-binding protein cDNA alters immune response profiles and fails to enhance protection induced by Sm14 DNA vaccine alone.

Science.gov (United States)

Fonseca, Cristina T; Pacífico, Lucila G G; Barsante, Michele M; Rassi, Tatiana; Cassali, Geovanni D; Oliveira, Sérgio C

2006-08-01

Schistosomiasis is an endemic disease that affects 200 million people worldwide. DNA-based vaccine is a promising strategy to induce protective immunity against schistosomiasis, since both humoral and cellular immune responses are involved in parasite elimination. In this study, we evaluated the ability of Sm14 cDNA alone or in association with a plasmid expressing murine interleukin (IL)-12 to induce protection against challenge infection. Mice were immunized with four doses of the DNA vaccine and the levels of protection were determined by worm burden recovery after challenge infection. Specific antibody production to rSm14 was determined by ELISA, and cytokine production was measured in splenocyte culture supernatants stimulated with rSm14 and in bronchoalveolar lavage of vaccinated mice after challenge infection. DNA immunization with pCI/Sm14 alone induced 40.5% of worm reduction. However, the use of pCI/IL-12 as adjuvant to pCI/Sm14 immunization failed to enhance protection against challenge infection. Protection induced by pCI/Sm14 immunization correlates with specific IgG antibody production against Sm14, Th1 type of immune response with high levels of interferon (IFN)-gamma and low levels of IL-4 in splenocyte culture supernatants and in bronchoalveolar lavage after challenge infection. IL-12 co-administration with pCI/Sm14 induced a significant production of nitric oxide in splenocyte culture supernatants and also lymphocyte suppression, with reduced percentage of T cells producing IFN-gamma and tumor necrosis factor-alpha.

[Influence of Leukodeplated Blood Transfusion on Cellular Immunity of Acute Leukemia Patients].

Science.gov (United States)

Lu, Ya-Lan; Zhang, Xin; Wang, Yu-Fang; Ke, Shan-Dong; Ke, Jin-Yong; Liu, Geng-Fu; Chen, Shi-Ming

2016-08-01

To study the influence of leukodeplated blood transfusion on cellular immunity of patients with acute leuemia, so as to provide support for application of leuko-deplated blood transfusion in clinic. A total of 100 AL patients from January 2012 to December 2015 were chosen, and were divided into 2 groups: leukodeplated blood transfusion group(50 cases) and routine blood transfusion group(RBT) as control (50 cases). The effective rate, side effects, peripheral blood T cells and expression level of TLR2 and TLR4 were compared between 2 groups. The expression levels CD3(+), CD4(+), CD8(+), CD4(+)/CD8(+) of TLR2 and TLR4 in control group were (52.18±2.14)%, （27.28±1.19）%,（24.21±1.65）%,1.22±0.18,0.62±0.04 and 0.57±0.05, respectively, after treatment; while these indicators in LdBT group were （52.18±2.14）%,（30.97±2.01）%,（27.08±1.55）%,1.39±0.24,0.91±0.06 and 0.87±0.07, respectively, and above-mentioned indicators in LdBT group were significantly higher than those in control group（P0.05）. The rate of side effects in study group was 6% (3/50), 18% (9/50) in control group, with statistically significance difference （Pblood transfusion can improve the cellular immunity of AL patients, and reduce the rate of side effects.

Optimal channel utilization and service protection in cellular communication systems

DEFF Research Database (Denmark)

Iversen, Villy Bæk

1997-01-01

In mobile communications an efficient utilization of the channels is of great importance.In this paper we consider the basic principles for obtaining the maximum utilization, and we study strategies for obtaining these limits.In general a high degree of sharing is efficient, but requires service...... protection mechanisms for protecting services and subscriber groups.We study cellular systems with overlaid cells, and the effect of overlapping cells, and we show that by dynamic channel allocation we obtain a high utilization.The models are generalizations of the Erlang-B formula, and can be evaluated...

Transfer of maternal immunity to piglets is involved in early protection against Mycoplasma hyosynoviae infection

DEFF Research Database (Denmark)

Lauritsen, Klara Tølbøl; Hagedorn-Olsen, Tine; Jungersen, Gregers

2017-01-01

Mycoplasma hyosynoviae causes arthritis in pigs older than 12 weeks. The role of colostrum in protection of piglets against M. hyosynoviae infection is not clear. Our objective was therefore to investigate whether transfer of maternal immunity to piglets was involved in early protection against...... immune response that complements the maternally transferred immune factors. Evident from this study is that the general absence of M. hyosynoviae arthritis in piglets can be ascribed mainly to their immunological status....

Protective effect of gallic acid and Syzygium cumini extract against oxidative stress-induced cellular injury in human lymphocytes.

Science.gov (United States)

De Bona, Karine Santos; Bonfanti, Gabriela; Bitencourt, Paula Eliete Rodrigues; da Silva, Thainan Paz; Borges, Raphaela Maleski; Boligon, Aline; Pigatto, Aline; Athayde, Margareth Lynde; Moretto, Maria Beatriz

2016-01-01

Syzygium cumini (Myrtaceae) presents antioxidant, anti-inflammatory, hypoglycemic and antibacterial effects; however, the cellular and molecular mechanisms of action in the immune system are not yet completely elucidated. This study evaluates the in vitro effect of gallic acid and aqueous S. cumini leaf extract (ASc) on adenosine deaminase (ADA) and dipeptidyl peptidase IV (DPP-IV) activities, cell viability and oxidative stress parameters in lymphocytes exposed to 2, 2'-azobis-2-amidinopropane dihydrochloride (AAPH). Lymphocytes were incubated with ASc (100 and 500 µg/ml) and gallic acid (50 and 200 µM) at 37 °C for 30 min followed by incubation with AAPH (1 mM) at 37 °C for 2 h. After the incubation time, the lymphocytes were used for determinations of ADA, DPP-IV and lactate dehydrogenase (LDH) activities, lipid peroxidation, protein thiol (P-SH) group levels and cellular viability by colorimetric methods. (i) HPLC fingerprinting of ASc revealed the presence of catechin, epicatechin, rutin, quercitrin, isoquercitrin, quercetin, kaempferol and chlorogenic, caffeic, gallic and ellagic acids; (ii) for the first time, ASc reduced the AAPH-induced increase in ADA activity, but no effect was observed on DPP-IV activity; (iii) ASc increased P-SH groups and cellular viability and decreased LDH activity, but was not able to reduce the AAPH-induced lipid peroxidation; (iv) gallic acid showed less protective effects than ASc. ASc affects the purinergic system and may modulate adenosine levels, indicating that the extract of this plant exhibits immunomodulatory properties. ASc also may potentially prevent the cellular injury induced by oxidative stress, highlighting its cytoprotective effects.

Suppression of cellular immunity in obstructive jaundice is caused by endotoxins: a study with germ-free rats

NARCIS (Netherlands)

Greve, J. W.; Gouma, D. J.; Soeters, P. B.; Buurman, W. A.

1990-01-01

The increased susceptibility to infections after surgery in jaundiced patients is considered to be caused by an impairment of cellular immunity and/or nutritional status. Endotoxins are suggested to play a role in the pathogenesis. However, the mechanism of action is unknown. Germ-free rats were

Effects of Mushroom and Herb Polysaccharides on Cellular and Humoral Immune Responses of Eimeria tenella-Infected Chickens

NARCIS (Netherlands)

Guo, F.C.; Kwakkel, R.P.; Williams, B.A.; Parmentier, H.K.; Li, W.K.; Yang, Z.Q.; Verstegen, M.W.A.

2004-01-01

We investigated the effects of polysaccharide extracts from 2 mushrooms, Lentinus edodes (LenE) and Tremella fuciformis (TreE), and an herb, Astragalus membranaceus (AstE), on cellular and humoral immune responses of Eimeria tenella-infected chickens. A total of 150 broiler chicks were assigned to 5

Effect of psychological intervention in the form of relaxation and guided imagery on cellular immune function in normal healthy subjects. An overview

DEFF Research Database (Denmark)

Zachariae, R; Kristensen, J S; Hokland, P

1991-01-01

The present study measured the effects of relaxation and guided imagery on cellular immune function. During a period of 10 days 10 healthy subjects were given one 1-hour relaxation procedure and one combined relaxation and guided imagery procedure, instructing the subjects to imagine their immune...... on the immune defense and could form the basis of further studies on psychological intervention and immunological status. Udgivelsesdato: 1990-null...

Immunogenicity is unrelated to protective immunity when induced by soluble and particulate antigens from Nocardia brasiliensis in BALB/c mice.

Science.gov (United States)

Salinas-Carmona, Mario C; Ramos, Alma I; Pérez-Rivera, Isabel

2006-08-01

Cell-mediated immunity plays a major role in protection against intracellular microbes. Nocardia brasiliensis is a facultative intracellular pathogen that causes chronic actinomycetoma. In this work, we injected BALB/c mice with soluble P24 and particulate antigens from N. brasiliensis. A higher antibody titer and lymphocyte proliferation was induced by the particulate antigen than by the soluble antigen. However, five months after antigen injection, antibody concentration and lymphocyte proliferation were similar. An increase in CD45R and CD4 T cells was unrelated to protective immunity. Active immunization with soluble or particulate antigens induced complete protection during the primary immune response. This protective response was IgM mediated. The higher immunogenicity was not related to protective immunity since the particulate antigen induced protection similar to the soluble antigen. Using particulate antigens for vaccination guarantees a stronger immune response, local and systemic side effects, but not necessarily protection.

Delivery of antigen to nasal-associated lymphoid tissue microfold cells through secretory IgA targeting local dendritic cells confers protective immunity.

Science.gov (United States)

Rochereau, Nicolas; Pavot, Vincent; Verrier, Bernard; Jospin, Fabienne; Ensinas, Agathe; Genin, Christian; Corthésy, Blaise; Paul, Stéphane

2016-01-01

Transmission of mucosal pathogens relies on their ability to bind to the surfaces of epithelial cells, to cross this thin barrier, and to gain access to target cells and tissues, leading to systemic infection. This implies that pathogen-specific immunity at mucosal sites is critical for the control of infectious agents using these routes to enter the body. Although mucosal delivery would ensure the best onset of protective immunity, most of the candidate vaccines are administered through the parenteral route. The present study evaluates the feasibility of delivering the chemically bound p24gag (referred to as p24 in the text) HIV antigen through secretory IgA (SIgA) in nasal mucosae in mice. We show that SIgA interacts specifically with mucosal microfold cells present in the nasal-associated lymphoid tissue. p24-SIgA complexes are quickly taken up in the nasal cavity and selectively engulfed by mucosal dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin-positive dendritic cells. Nasal immunization with p24-SIgA elicits both a strong humoral and cellular immune response against p24 at the systemic and mucosal levels. This ensures effective protection against intranasal challenge with recombinant vaccinia virus encoding p24. This study represents the first example that underscores the remarkable potential of SIgA to serve as a carrier for a protein antigen in a mucosal vaccine approach targeting the nasal environment. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

The cellular immune response of Daphnia magna under host-parasite genetic variation and variation in initial dose.

Science.gov (United States)

Auld, Stuart K J R; Edel, Kai H; Little, Tom J

2012-10-01

In invertebrate-parasite systems, the likelihood of infection following parasite exposure is often dependent on the specific combination of host and parasite genotypes (termed genetic specificity). Genetic specificity can maintain diversity in host and parasite populations and is a major component of the Red Queen hypothesis. However, invertebrate immune systems are thought to only distinguish between broad classes of parasite. Using a natural host-parasite system with a well-established pattern of genetic specificity, the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa, we found that only hosts from susceptible host-parasite genetic combinations mounted a cellular response following exposure to the parasite. These data are compatible with the hypothesis that genetic specificity is attributable to barrier defenses at the site of infection (the gut), and that the systemic immune response is general, reporting the number of parasite spores entering the hemocoel. Further supporting this, we found that larger cellular responses occurred at higher initial parasite doses. By studying the natural infection route, where parasites must pass barrier defenses before interacting with systemic immune responses, these data shed light on which components of invertebrate defense underlie genetic specificity. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

[Effect of immune modulation on immunogenic and protective activity of a live plague vaccine].

Science.gov (United States)

Karal'nik, B V; Ponomareva, T S; Deriabin, P N; Denisova, T G; Mel'nikova, N N; Tugambaev, T I; Atshabar, B B; Zakarian, S B

2014-01-01

Comparative evaluation of the effect of polyoxidonium and betaleukin on immunogenic and protective activity of a live plague vaccine in model animal experiments. Plague vaccine EV, polyoxidonium, betaleukin, erythrocytic antigenic diagnosticum for determination of F1 antibodies and immune reagents for detection of lymphocytes with F1 receptors (LFR) in adhesive test developed by the authors were used. The experiments were carried out in 12 rabbits and 169 guinea pigs. Immune modulation accelerated the appearance and disappearance of LFR (early phase) and ensured a more rapid and intensive antibody formation (effector phase). Activation by betaleukin is more pronounced than by polyoxidonium. The more rapid and intensive was the development of early phase, the more effective was antibody response to the vaccine. Immune modulation in the experiment with guinea pigs significantly increased protective activity of the vaccine. The use of immune modulators increased immunogenic (in both early and effector phases of antigen-specific response) and protective activity of the EV vaccine. A connection between the acceleration of the first phase of antigen-specific response and general intensity of effector phase of immune response to the EV vaccine was detected. ,

Identification of immune correlates of protection in Shigella infection by application of machine learning.

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Arevalillo, Jorge M; Sztein, Marcelo B; Kotloff, Karen L; Levine, Myron M; Simon, Jakub K

2017-10-01

Immunologic correlates of protection are important in vaccine development because they give insight into mechanisms of protection, assist in the identification of promising vaccine candidates, and serve as endpoints in bridging clinical vaccine studies. Our goal is the development of a methodology to identify immunologic correlates of protection using the Shigella challenge as a model. The proposed methodology utilizes the Random Forests (RF) machine learning algorithm as well as Classification and Regression Trees (CART) to detect immune markers that predict protection, identify interactions between variables, and define optimal cutoffs. Logistic regression modeling is applied to estimate the probability of protection and the confidence interval (CI) for such a probability is computed by bootstrapping the logistic regression models. The results demonstrate that the combination of Classification and Regression Trees and Random Forests complements the standard logistic regression and uncovers subtle immune interactions. Specific levels of immunoglobulin IgG antibody in blood on the day of challenge predicted protection in 75% (95% CI 67-86). Of those subjects that did not have blood IgG at or above a defined threshold, 100% were protected if they had IgA antibody secreting cells above a defined threshold. Comparison with the results obtained by applying only logistic regression modeling with standard Akaike Information Criterion for model selection shows the usefulness of the proposed method. Given the complexity of the immune system, the use of machine learning methods may enhance traditional statistical approaches. When applied together, they offer a novel way to quantify important immune correlates of protection that may help the development of vaccines. Copyright © 2017 Elsevier Inc. All rights reserved.

Glutamine's protection against cellular injury is dependent on heat shock factor-1.

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Morrison, Angela L; Dinges, Martin; Singleton, Kristen D; Odoms, Kelli; Wong, Hector R; Wischmeyer, Paul E

2006-06-01

Glutamine (GLN) has been shown to protect cells, tissues, and whole organisms from stress and injury. Enhanced expression of heat shock protein (HSP) has been hypothesized to be responsible for this protection. To date, there are no clear mechanistic data confirming this relationship. This study tested the hypothesis that GLN-mediated activation of the HSP pathway via heat shock factor-1 (HSF-1) is responsible for cellular protection. Wild-type HSF-1 (HSF-1(+/+)) and knockout (HSF-1(-/-)) mouse fibroblasts were used in all experiments. Cells were treated with GLN concentrations ranging from 0 to 16 mM and exposed to heat stress injury in a concurrent treatment model. Cell viability was assayed with phenazine methosulfate plus tetrazolium salt, HSP-70, HSP-25, and nuclear HSF-1 expression via Western blot analysis, and HSF-1/heat shock element (HSE) binding via EMSA. GLN significantly attenuated heat-stress induced cell death in HSF-1(+/+) cells in a dose-dependent manner; however, the survival benefit of GLN was lost in HSF-1(-/-) cells. GLN led to a dose-dependent increase in HSP-70 and HSP-25 expression after heat stress. No inducible HSP expression was observed in HSF-1(-/-) cells. GLN increased unphosphorylated HSF-1 in the nucleus before heat stress. This was accompanied by a GLN-mediated increase in HSF-1/HSE binding and nuclear content of phosphorylated HSF-1 after heat stress. This is the first demonstration that GLN-mediated cellular protection after heat-stress injury is related to HSF-1 expression and cellular capacity to activate an HSP response. Furthermore, the mechanism of GLN-mediated protection against injury appears to involve an increase in nuclear HSF-1 content before stress and increased HSF-1 promoter binding and phosphorylation.

Giardiasis in mice: analysis of humoral and cellular immune responses to Giardia muris.

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Anders, R F; Roberts-Thomson, I C; Mitchell, G F

1982-01-01

Humoral and cellular immune responses have been evaluated in two inbred strains of mice which differ markedly in their susceptibility to infection with Giardia muris. Serum IgG and IgA antibody levels and IgA levels in intestinal washes were determined by a solid-phase radioimmunoassay using G. muris antigen prepared by sonication of trophozoites, while cell-mediated immunity was assessed by a radiometric ear-assay for delayed-type hypersensitivity. Following infection of BALB/c mice (resistant) and C3H/He mice (susceptible), the IgG and IgA antibody levels in serum progressively increased over the period of study with C3H/He mice having significantly higher titres of IgA antibodies than BALB/c late in the infection. Systemic immunization with G. muris trophozoites resulted in high titres of IgG antibodies in the serum. IgA antibodies were detected in intestinal washes 2 weeks after infection with a subsequent fall in levels in BALB/c mice but a progressive increase levels in C3H/He mice. Prior immunization resulted in IgA antibodies being detected earlier in the intestinal washings after a challenge infection. Delayed-type hypersensitivity to G. muris antigens could not be detected during an infection but a positive response was elicited following antigen priming in mice pretreated with cyclophosphamide. The immune responses evaluated in this study were assessed using a whole G. muris trophozoite sonicate and variations in the quantitative aspects of the responses did not account for observed differences in the course of infection in the two strains of mice.

The fungal quorum-sensing molecule farnesol activates innate immune cells but suppresses cellular adaptive immunity.

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Leonhardt, Ines; Spielberg, Steffi; Weber, Michael; Albrecht-Eckardt, Daniela; Bläss, Markus; Claus, Ralf; Barz, Dagmar; Scherlach, Kirstin; Hertweck, Christian; Löffler, Jürgen; Hünniger, Kerstin; Kurzai, Oliver

2015-03-17

Farnesol, produced by the polymorphic fungus Candida albicans, is the first quorum-sensing molecule discovered in eukaryotes. Its main function is control of C. albicans filamentation, a process closely linked to pathogenesis. In this study, we analyzed the effects of farnesol on innate immune cells known to be important for fungal clearance and protective immunity. Farnesol enhanced the expression of activation markers on monocytes (CD86 and HLA-DR) and neutrophils (CD66b and CD11b) and promoted oxidative burst and the release of proinflammatory cytokines (tumor necrosis factor alpha [TNF-α] and macrophage inflammatory protein 1 alpha [MIP-1α]). However, this activation did not result in enhanced fungal uptake or killing. Furthermore, the differentiation of monocytes to immature dendritic cells (iDC) was significantly affected by farnesol. Several markers important for maturation and antigen presentation like CD1a, CD83, CD86, and CD80 were significantly reduced in the presence of farnesol. Furthermore, farnesol modulated migrational behavior and cytokine release and impaired the ability of DC to induce T cell proliferation. Of major importance was the absence of interleukin 12 (IL-12) induction in iDC generated in the presence of farnesol. Transcriptome analyses revealed a farnesol-induced shift in effector molecule expression and a down-regulation of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor during monocytes to iDC differentiation. Taken together, our data unveil the ability of farnesol to act as a virulence factor of C. albicans by influencing innate immune cells to promote inflammation and mitigating the Th1 response, which is essential for fungal clearance. Farnesol is a quorum-sensing molecule which controls morphological plasticity of the pathogenic yeast Candida albicans. As such, it is a major mediator of intraspecies communication. Here, we investigated the impact of farnesol on human innate immune cells known to be

Protective Immunity against Hepatitis C: Many Shades of Grey

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Mohamed S Abdel-Hakeem

2014-06-01

Full Text Available The majority of individuals who become acutely infected with hepatitis C virus (HCV develop chronic infection and suffer from progressive liver damage while approximately 25% are able to eliminate the virus spontaneously. Despite the recent introduction of new direct-acting antivirals (DAAs, there is still no vaccine for HCV. As a result, new infections and reinfections will remain a problem in developing countries and among high risk populations like injection drug users (IDUs who have limited access to treatment and who continue to be exposed to the virus. The outcome of acute HCV is determined by the interplay between the host genetics, the virus and the virus-specific immune response. Studies in humans and chimpanzees have demonstrated the essential role of HCV-specific CD4 and CD8 T cell responses in protection against viral persistence. Recent data suggest that antibody responses play a more important role than what was previously thought. Individuals who spontaneously resolve acute HCV infection develop long-lived memory T cells and are less likely to become persistently infected upon re-exposure. New studies examining high risk cohorts are identifying correlates of protection during real life exposures and reinfections. In this review, we discuss correlates of protective immunity during acute HCV and upon reexposure. We draw parallels between HCV and the current knowledge about protective memory in other models of chronic viral infections. Finally, we discuss some of the yet unresolved questions about key correlates of protection and their relevance for vaccine development against HCV.

Prolonged protection against Intranasal challenge with influenza virus following systemic immunization or combinations of mucosal and systemic immunizations with a heat-labile toxin mutant.

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Zhou, Fengmin; Goodsell, Amanda; Uematsu, Yasushi; Vajdy, Michael

2009-04-01

Seasonal influenza virus infections cause considerable morbidity and mortality in the world, and there is a serious threat of a pandemic influenza with the potential to cause millions of deaths. Therefore, practical influenza vaccines and vaccination strategies that can confer protection against intranasal infection with influenza viruses are needed. In this study, we demonstrate that using LTK63, a nontoxic mutant of the heat-labile toxin from Escherichia coli, as an adjuvant for both mucosal and systemic immunizations, systemic (intramuscular) immunization or combinations of mucosal (intranasal) and intramuscular immunizations protected mice against intranasal challenge with a lethal dose of live influenza virus at 3.5 months after the second immunization.

State of cellular and humoral immune system in women of reproductive age with tumor-like ovary formations

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O. S. Shapoval

2014-12-01

Full Text Available Aim. Violations occurring in the immune system in women with ovary tumor-like formations are one of the most important factors in the pathogenesis and development of the disease. In order to study features of immune disorders in 105 women of reproductive age with tumor-like ovary formations determination of cellular and humoral immunity indices was carried out. Methods and results. Variants of immunological reactivity in women with tumor-like ovary formations with different possibilities of reproductive function implementing were established. Conclusion. This indicates that the identification of one of the variants of immunological reactivity disorder in the precurative stage is one of the components of the effective prescribed therapy necessary to select the appropriate tactics of medical correction of homeostasis.

Mucosal delivery of a vectored RSV vaccine is safe and elicits protective immunity in rodents and nonhuman primates

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Angiolo Pierantoni

Full Text Available Respiratory Syncytial Virus (RSV is a leading cause of severe respiratory disease in infants and the elderly. No vaccine is presently available to address this major unmet medical need. We generated a new genetic vaccine based on chimpanzee Adenovirus (PanAd3-RSV and Modified Vaccinia Ankara RSV (MVA-RSV encoding the F, N, and M2-1 proteins of RSV, for the induction of neutralizing antibodies and broad cellular immunity. Because RSV infection is restricted to the respiratory tract, we compared intranasal (IN and intramuscular (M administration for safety, immunogenicity, and efficacy in different species. A single IN or IM vaccination completely protected BALB/c mice and cotton rats against RSV replication in the lungs. However, only IN administration could prevent infection in the upper respiratory tract. IM vaccination with MVA-RSV also protected cotton rats from lower respiratory tract infection in the absence of detectable neutralizing antibodies. Heterologous prime boost with PanAd3-RSV and MVA-RSV elicited high neutralizing antibody titers and broad T-cell responses in nonhuman primates. In addition, animals primed in the nose developed mucosal IgA against the F protein. In conclusion, we have shown that our vectored RSV vaccine induces potent cellular and humoral responses in a primate model, providing strong support for clinical testing.

Hypoxia Promotes Tumor Growth in Linking Angiogenesis to Immune Escape

OpenAIRE

Chouaib, Salem; Messai, Yosra; Couve, Sophie; Escudier, Bernard; Hasmim, Meriem; Noman, Muhammad Zaeem

2012-01-01

Despite the impressive progress over the past decade, in the field of tumor immunology, such as the identification of tumor antigens and antigenic peptides, there are still many obstacles in eliciting an effective immune response to eradicate cancer. It has become increasingly clear that tumor microenvironment plays a crucial role in the control of immune protection. Tumors have evolved to utilize hypoxic stress to their own advantage by activating key biochemical and cellular pathways that a...

Evaluation of cellular responses for a chimeric HBsAg-HCV core DNA vaccine in BALB/c mice

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Maryam Yazdanian

2015-01-01

Conclusion: Fusion of HBsAg to HCVcp in the context of a DNA vaccine modality could augment Th1-oriented cellular and CTL responses toward a protective epitope, comparable to that of HCVcp (subunit HCV vaccine immunization.

Local Th17/IgA immunity correlate with protection against intranasal infection with Streptococcus pyogenes

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Mortensen, Rasmus; Christensen, Dennis; Hansen, Lasse Bøllehuus

2017-01-01

Streptococcus pyogenes (group A streptococcus, GAS) is responsible for a wide array of infections. Respiratory transmission via droplets is the most common mode of transmission but it may also infect the host via other routes such as lesions in the skin. To advance the development of a future...... vaccine against GAS, it is therefore important to investigate how protective immunity is related to the route of vaccine administration. To explore this, we examined whether a parenterally administered anti-GAS vaccine could protect against an intranasal GAS infection or if this would require locally...... primed immunity. We foundd that a parenteral CAF01 adjuvanted GAS vaccine offered no protection against intranasal infection despite inducing strong systemic Th1/Th17/IgG immunity that efficiently protected against an intraperitoneal GAS infection. However, the same vaccine administered via...

Protection of Broiler Chicks Housed with Immunized Cohorts Against Infection with Eimeria maxima and E. acervulina.

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Fetterer, Raymond H; Barfield, Ruth C; Jenkins, Mark C

2015-03-01

The use of live oocyst vaccines is becoming increasingly important in the control of avian coccidiosis in broilers. Knowledge of the mechanisms employed when chicks uptake oocysts and become immune is important for optimizing delivery of live vaccines. The current study tests the hypothesis that chicks not initially immunized may ingest oocysts by contact with litter containing oocysts shed by immunized cohorts. In Experiment 1, day-old broiler chicks were housed in pens containing clean litter. In Trial 1, 100% of chicks in some pens were immunized with 2.5 X 10(3) Eimeria acervulina oocysts while in other pens only 75% of chicks were immunized and remaining cohorts within the pens were not immunized. Other pens contained chicks that served as nonimmunized nonchallenged controls or nonimmunized challenged controls (NIC). On day 21, birds were given a homologous challenge of 6 X 10(5) oocysts. A second identical trial was conducted, except birds were immunized with 500 Eimeria maxima oocysts and were challenged with 3 X 10(3) E. maxima oocysts. In Experiment 2, 100% of chicks in some pens were immunized with 500 E. acervulina oocysts while in other pens either 75% or 50% of the birds were immunized. On day 14, birds were challenged with 1 X 10(6) oocysts. Trial 2 was identical to Trial 1 except that birds were immunized with 100 E. maxima oocysts and challenged with 1 X 10(6) oocysts. For all experiments weight gain, feed conversion ratio (FCR), plasma carotenoids, and litter oocyst counts were measured. In Experiment 1, the level of protection in groups containing 25% nonimmunized cohorts, as measured by weight gain, carotenoid level, FCR, and oocyst litter counts, was identical to groups containing 100% immunized chicks. In Experiment 2, pens where 50% or 75% of birds were immunized with either E. maxima or E. acervulina were not well protected from decreases in weight gain and plasma carotenoids nor from increases in litter oocyst counts following a challenge

Anthrax lethal factor as an immune target in humans and transgenic mice and the impact of HLA polymorphism on CD4+ T cell immunity.

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Ascough, Stephanie; Ingram, Rebecca J; Chu, Karen K; Reynolds, Catherine J; Musson, Julie A; Doganay, Mehmet; Metan, Gökhan; Ozkul, Yusuf; Baillie, Les; Sriskandan, Shiranee; Moore, Stephen J; Gallagher, Theresa B; Dyson, Hugh; Williamson, E Diane; Robinson, John H; Maillere, Bernard; Boyton, Rosemary J; Altmann, Daniel M

2014-05-01

Bacillus anthracis produces a binary toxin composed of protective antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). Most studies have concentrated on induction of toxin-specific antibodies as the correlate of protective immunity, in contrast to which understanding of cellular immunity to these toxins and its impact on infection is limited. We characterized CD4+ T cell immunity to LF in a panel of humanized HLA-DR and DQ transgenic mice and in naturally exposed patients. As the variation in antigen presentation governed by HLA polymorphism has a major impact on protective immunity to specific epitopes, we examined relative binding affinities of LF peptides to purified HLA class II molecules, identifying those regions likely to be of broad applicability to human immune studies through their ability to bind multiple alleles. Transgenics differing only in their expression of human HLA class II alleles showed a marked hierarchy of immunity to LF. Immunogenicity in HLA transgenics was primarily restricted to epitopes from domains II and IV of LF and promiscuous, dominant epitopes, common to all HLA types, were identified in domain II. The relevance of this model was further demonstrated by the fact that a number of the immunodominant epitopes identified in mice were recognized by T cells from humans previously infected with cutaneous anthrax and from vaccinated individuals. The ability of the identified epitopes to confer protective immunity was demonstrated by lethal anthrax challenge of HLA transgenic mice immunized with a peptide subunit vaccine comprising the immunodominant epitopes that we identified.

Interferon-γ, a valuable surrogate marker of Plasmodium falciparum pre-erythrocytic stages protective immunity

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BenMohamed Lbachir

2011-02-01

Full Text Available Abstract Immunity against the pre-erythrocytic stages of malaria is the most promising, as it is strong and fully sterilizing. Yet, the underlying immune effectors against the human Plasmodium falciparum pre-erythrocytic stages remain surprisingly poorly known and have been little explored, which in turn prevents any rational vaccine progress. Evidence that has been gathered in vitro and in vivo, in higher primates and in humans, is reviewed here, emphasizing the significant role of IFN-γ, either as a critical immune mediator or at least as a valuable surrogate marker of protection. One may hope that these results will trigger investigations in volunteers immunized either by optimally irradiated or over-irradiated sporozoites, to quickly delineate better surrogates of protection, which are essential for the development of a successful malaria vaccine.

Induction of complex immune responses and strong protection against retrovirus challenge by adenovirus-based immunization depends on the order of vaccine delivery.

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Kaulfuß, Meike; Wensing, Ina; Windmann, Sonja; Hrycak, Camilla Patrizia; Bayer, Wibke

2017-02-06

In the Friend retrovirus mouse model we developed potent adenovirus-based vaccines that were designed to induce either strong Friend virus GagL 85-93 -specific CD8 + T cell or antibody responses, respectively. To optimize the immunization outcome we evaluated vaccination strategies using combinations of these vaccines. While the vaccines on their own confer strong protection from a subsequent Friend virus challenge, the simple combination of the vaccines for the establishment of an optimized immunization protocol did not result in a further improvement of vaccine effectivity. We demonstrate that the co-immunization with GagL 85-93 /leader-gag encoding vectors together with envelope-encoding vectors abrogates the induction of GagL 85-93 -specific CD8 + T cells, and in successive immunization protocols the immunization with the GagL 85-93 /leader-gag encoding vector had to precede the immunization with an envelope encoding vector for the efficient induction of GagL 85-93 -specific CD8 + T cells. Importantly, the antibody response to envelope was in fact enhanced when the mice were adenovirus-experienced from a prior immunization, highlighting the expedience of this approach. To circumvent the immunosuppressive effect of envelope on immune responses to simultaneously or subsequently administered immunogens, we developed a two immunizations-based vaccination protocol that induces strong immune responses and confers robust protection of highly Friend virus-susceptible mice from a lethal Friend virus challenge.

Social Immunity: Emergence and Evolution of Colony-Level Disease Protection.

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Cremer, Sylvia; Pull, Christopher D; Fürst, Matthias A

2018-01-07

Social insect colonies have evolved many collectively performed adaptations that reduce the impact of infectious disease and that are expected to maximize their fitness. This colony-level protection is termed social immunity, and it enhances the health and survival of the colony. In this review, we address how social immunity emerges from its mechanistic components to produce colony-level disease avoidance, resistance, and tolerance. To understand the evolutionary causes and consequences of social immunity, we highlight the need for studies that evaluate the effects of social immunity on colony fitness. We discuss the roles that host life history and ecology have on predicted eco-evolutionary dynamics, which differ among the social insect lineages. Throughout the review, we highlight current gaps in our knowledge and promising avenues for future research, which we hope will bring us closer to an integrated understanding of socio-eco-evo-immunology.

Exercise protects from cancer through regulation of immune function and inflammation

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Hojman, Pernille

2017-01-01

Exercise training has been extensively studied in cancer settings as part of prevention or rehabilitation strategies, yet emerging evidence suggests that exercise training can also directly affect tumor-specific outcomes. The underlying mechanisms for this exercise-dependent cancer protection are...... regulation of immune and inflammatory functions, and exercise may be pursued as anticancer treatment through incorporation into standard oncological therapy to the benefit of the cancer patients.......Exercise training has been extensively studied in cancer settings as part of prevention or rehabilitation strategies, yet emerging evidence suggests that exercise training can also directly affect tumor-specific outcomes. The underlying mechanisms for this exercise-dependent cancer protection...... are just starting to be elucidated. To this end, evasion of immune surveillance and tumor-associated inflammation are established as hallmarks of cancer, and exercise may target cancer incidence and progression through regulation of these mechanisms. Here, I review the role of exercise in protection from...

Lessons Learned from Protective Immune Responses to Optimize Vaccines against Cryptosporidiosis.

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Lemieux, Maxime W; Sonzogni-Desautels, Karine; Ndao, Momar

2017-12-24

In developing countries, cryptosporidiosis causes moderate-to-severe diarrhea and kills thousands of infants and toddlers annually. Drinking and recreational water contaminated with Cryptosporidium spp. oocysts has led to waterborne outbreaks in developed countries. A competent immune system is necessary to clear this parasitic infection. A better understanding of the immune responses required to prevent or limit infection by this protozoan parasite is the cornerstone of development of an effective vaccine. In this light, lessons learned from previously developed vaccines against Cryptosporidium spp. are at the foundation for development of better next-generation vaccines. In this review, we summarize the immune responses elicited by naturally and experimentally-induced Cryptosporidium spp. infection and by several experimental vaccines in various animal models. Our aim is to increase awareness about the immune responses that underlie protection against cryptosporidiosis and to encourage promotion of these immune responses as a key strategy for vaccine development. Innate and mucosal immunity will be addressed as well as adaptive immunity, with an emphasis on the balance between T H 1/T H 2 immune responses. Development of more effective vaccines against cryptosporidiosis is needed to prevent Cryptosporidium spp.-related deaths in infants and toddlers in developing countries.

Toll-like receptor agonist augments virus-like particle-mediated protection from Ebola virus with transient immune activation.

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Karen A O Martins

Full Text Available Identifying safe and effective adjuvants is critical for the advanced development of protein-based vaccines. Pattern recognition receptor (PRR agonists are increasingly being explored as potential adjuvants, but there is concern that the efficacy of these molecules may be dependent on potentially dangerous levels of non-specific immune activation. The filovirus virus-like particle (VLP vaccine protects mice, guinea pigs, and nonhuman primates from viral challenge. In this study, we explored the impact of a stabilized dsRNA mimic, polyICLC, on VLP vaccination of C57BL/6 mice and Hartley guinea pigs. We show that at dose levels as low as 100 ng, the adjuvant increased the efficacy of the vaccine in mice. Antigen-specific, polyfunctional CD4 and CD8 T cell responses and antibody responses increased significantly upon inclusion of adjuvant. To determine whether the efficacy of polyICLC correlated with systemic immune activation, we examined serum cytokine levels and cellular activation in the draining lymph node. PolyICLC administration was associated with increases in TNFα, IL6, MCP1, MIP1α, KC, and MIP1β levels in the periphery and with the activation of dendritic cells (DCs, NK cells, and B cells. However, this activation resolved within 24 to 72 hours at efficacious adjuvant dose levels. These studies are the first to examine the polyICLC-induced enhancement of antigen-specific immune responses in the context of non-specific immune activation, and they provide a framework from which to consider adjuvant dose levels.

Social immunity and the superorganism: Behavioral defenses protecting honey bee colonies from pathogens and parasites

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Honey bees (Apis mellifera) have a number of traits that effectively reduce the spread of pathogens and parasites throughout the colony. These mechanisms of social immunity are often analogous to the individual immune system. As such social immune defences function to protect the colony or superorga...

A protective effect of epidermal powder immunization in a mouse model of equine herpesvirus-1 infection

International Nuclear Information System (INIS)

Kondo, Takashi; McGregor, Martha; Chu, Qili; Chen, Dexiang; Horimoto, Taisuke; Kawaoka, Yoshihiro

2004-01-01

To evaluate the protective effect of epidermal powder immunization (EPI) against equine herpesvirus-1 (EHV-1) infection, we prepared a powder vaccine in which formalin-inactivated virions were embedded in water-soluble, sugar-based particles. A PowderJect device was used to immunize mice with the powder vaccine via their abdominal skin. We found that twice-immunized mice were protected against challenge with the wild-type virus. This protective effect was equivalent to or better than that observed in mice immunized with other types of vaccines, including a gene gun-mediated DNA vaccine containing the glycoprotein D (gD) gene or conventional inactivated virus vaccines introduced via intramuscular or intranasal injections. These findings indicate that the powder vaccine is a promising approach for the immunological control of EHV-1 infection, either alone or as a part of prime-boost vaccination strategies

Intranasal immunization with protective antigen of Bacillus anthracis induces a long-term immunological memory response.

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Woo, Sun-Je; Kang, Seok-Seong; Park, Sung-Moo; Yang, Jae Seung; Song, Man Ki; Yun, Cheol-Heui; Han, Seung Hyun

2015-10-01

Although intranasal vaccination has been shown to be effective for the protection against inhalational anthrax, establishment of long-term immunity has yet to be achieved. Here, we investigated whether intranasal immunization with recombinant protective antigen (rPA) of Bacillus anthracis induces immunological memory responses in the mucosal and systemic compartments. Intranasal immunization with rPA plus cholera toxin (CT) sustained PA-specific antibody responses for 6 months in lung, nasal washes, and vaginal washes as well as serum. A significant induction of PA-specific memory B cells was observed in spleen, cervical lymph nodes (CLNs) and lung after booster immunization. Furthermore, intranasal immunization with rPA plus CT remarkably generated effector memory CD4(+) T cells in the lung. PA-specific CD4(+) T cells preferentially increased the expression of Th1- and Th17-type cytokines in lung, but not in spleen or CLNs. Collectively, the intranasal immunization with rPA plus CT promoted immunologic memory responses in the mucosal and systemic compartments, providing long-term immunity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Humoral and cellular immune responses to Yersinia pestis Pla antigen in humans immunized with live plague vaccine.

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Feodorova, Valentina A; Lyapina, Anna M; Khizhnyakova, Maria A; Zaitsev, Sergey S; Sayapina, Lidiya V; Arseneva, Tatiana E; Trukhachev, Alexey L; Lebedeva, Svetlana A; Telepnev, Maxim V; Ulianova, Onega V; Lyapina, Elena P; Ulyanov, Sergey S; Motin, Vladimir L

2018-06-01

To establish correlates of human immunity to the live plague vaccine (LPV), we analyzed parameters of cellular and antibody response to the plasminogen activator Pla of Y. pestis. This outer membrane protease is an essential virulence factor that is steadily expressed by Y. pestis. PBMCs and sera were obtained from a cohort of naïve (n = 17) and LPV-vaccinated (n = 34) donors. Anti-Pla antibodies of different classes and IgG subclasses were determined by ELISA and immunoblotting. The analysis of antibody response was complicated with a strong reactivity of Pla with normal human sera. The linear Pla B-cell epitopes were mapped using a library of 15-mer overlapping peptides. Twelve peptides that reacted specifically with sera of vaccinated donors were found together with a major cross-reacting peptide IPNISPDSFTVAAST located at the N-terminus. PBMCs were stimulated with recombinant Pla followed by proliferative analysis and cytokine profiling. The T-cell recall response was pronounced in vaccinees less than a year post-immunization, and became Th17-polarized over time after many rounds of vaccination. The Pla protein can serve as a biomarker of successful vaccination with LPV. The diagnostic use of Pla will require elimination of cross-reactive parts of the antigen.

Mucosal Immunity and Protective Efficacy of Intranasal Inactivated Influenza Vaccine Is Improved by Chitosan Nanoparticle Delivery in Pigs.

Science.gov (United States)

Dhakal, Santosh; Renu, Sankar; Ghimire, Shristi; Shaan Lakshmanappa, Yashavanth; Hogshead, Bradley T; Feliciano-Ruiz, Ninoshkaly; Lu, Fangjia; HogenEsch, Harm; Krakowka, Steven; Lee, Chang Won; Renukaradhya, Gourapura J

2018-01-01

Annually, swine influenza A virus (SwIAV) causes severe economic loss to swine industry. Currently used inactivated SwIAV vaccines administered by intramuscular injection provide homologous protection, but limited heterologous protection against constantly evolving field viruses, attributable to the induction of inadequate levels of mucosal IgA and cellular immune responses in the respiratory tract. A novel vaccine delivery platform using mucoadhesive chitosan nanoparticles (CNPs) administered through intranasal (IN) route has the potential to elicit strong mucosal and systemic immune responses in pigs. In this study, we evaluated the immune responses and cross-protective efficacy of IN chitosan encapsulated inactivated SwIAV vaccine in pigs. Killed SwIAV H1N2 (δ-lineage) antigens (KAg) were encapsulated in chitosan polymer-based nanoparticles (CNPs-KAg). The candidate vaccine was administered twice IN as mist to nursery pigs. Vaccinates and controls were then challenged with a zoonotic and virulent heterologous SwIAV H1N1 (γ-lineage). Pigs vaccinated with CNPs-KAg exhibited an enhanced IgG serum antibody and mucosal secretory IgA antibody responses in nasal swabs, bronchoalveolar lavage (BAL) fluids, and lung lysates that were reactive against homologous (H1N2), heterologous (H1N1), and heterosubtypic (H3N2) influenza A virus strains. Prior to challenge, an increased frequency of cytotoxic T lymphocytes, antigen-specific lymphocyte proliferation, and recall IFN-γ secretion by restimulated peripheral blood mononuclear cells in CNPs-KAg compared to control KAg vaccinates were observed. In CNPs-KAg vaccinated pigs challenged with heterologous virus reduced severity of macroscopic and microscopic influenza-associated pulmonary lesions were observed. Importantly, the infectious SwIAV titers in nasal swabs [days post-challenge (DPC) 4] and BAL fluid (DPC 6) were significantly ( p  influenza nanovaccine may be an ideal candidate vaccine for use in pigs, and pig is a

Cord blood Streptococcus pneumoniae-specific cellular immune responses predict early pneumococcal carriage in high-risk infants in Papua New Guinea.

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Francis, J P; Richmond, P C; Strickland, D; Prescott, S L; Pomat, W S; Michael, A; Nadal-Sims, M A; Edwards-Devitt, C J; Holt, P G; Lehmann, D; van den Biggelaar, A H J

2017-03-01

In areas where Streptococcus pneumoniae is highly endemic, infants experience very early pneumococcal colonization of the upper respiratory tract, with carriage often persisting into adulthood. We aimed to explore whether newborns in high-risk areas have pre-existing pneumococcal-specific cellular immune responses that may affect early pneumococcal acquisition. Cord blood mononuclear cells (CBMC) of 84 Papua New Guinean (PNG; high endemic) and 33 Australian (AUS; low endemic) newborns were stimulated in vitro with detoxified pneumolysin (dPly) or pneumococcal surface protein A (PspA; families 1 and 2) and compared for cytokine responses. Within the PNG cohort, associations between CBMC dPly and PspA-induced responses and pneumococcal colonization within the first month of life were studied. Significantly higher PspA-specific interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-5, IL-6, IL-10 and IL-13 responses, and lower dPly-IL-6 responses were produced in CBMC cultures of PNG compared to AUS newborns. Higher CBMC PspA-IL-5 and PspA-IL-13 responses correlated with a higher proportion of cord CD4 T cells, and higher dPly-IL-6 responses with a higher frequency of cord antigen-presenting cells. In the PNG cohort, higher PspA-specific IL-5 and IL-6 CBMC responses were associated independently and significantly with increased risk of earlier pneumococcal colonization, while a significant protective effect was found for higher PspA-IL-10 CBMC responses. Pneumococcus-specific cellular immune responses differ between children born in pneumococcal high versus low endemic settings, which may contribute to the higher risk of infants in high endemic settings for early pneumococcal colonization, and hence disease. © 2016 British Society for Immunology.

Active immunizations with peptide-DC vaccines and passive transfer with antibodies protect neutropenic mice against disseminated candidiasis.

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Xin, Hong

2016-01-04

We previously report that peptide-pulsed dendritic cell (DC) vaccination, which targeting two peptides (Fba and Met6) expressed on the cell surface of Candida albicans, can induce high degree of protection against disseminated candidiasis in immunocompetent mice. Passive transfer of immune sera from the peptide immunized mice or peptide-related monoclonal antibodies demonstrated that protection was medicated by peptide-specific antibodies. In this study the efficacy of active and passive immunization against disseminated candidiasis was tested in mice with cyclophosphamide-induced neutropenia. Peptide-DC vaccines were given to mice prior to induction of neutropenia. We show active immunization with either Fba or Met6 peptide-DC vaccine significantly improved the survival and reduced the fungal burden of disseminated candidiasis in those immunocompromised mice. Importantly, we show that administration of two protective monoclonal antibodies also protect neutropenic mice against the disease, implying possibility of developing a successful passive immunotherapy strategy to treat the disease and protect against disseminated candidiasis. The results of this study are crucial as they address the fundamental questions as to whether the synthetic peptide vaccine induced immunity protects the host during a neutropenic episode. We anticipate that this peptide-vaccine study will serve as the foundation of future investigations into new peptide vaccines comprised of cell surface peptides from other medically important Candida species, as well as other fungi. Copyright © 2015 Elsevier Ltd. All rights reserved.

Active Immunizations with Peptide-DC Vaccines and Passive Transfer with Antibodies Protect Neutropenic Mice against Disseminated Candidiasis

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Xin, Hong

2015-01-01

We previously report that peptide-pulsed dendritic cell (DC) vaccination, which targeting two peptides (Fba and Met6) expressed on the cell surface of Candida albicans, can induce high degree of protection against disseminated candidiasis in immunocompetent mice. Passive transfer of immune sera from the peptide immunized mice or peptide-related monoclonal antibodies demonstrated that protection was medicated by peptide-specific antibodies. In this study the efficacy of active and passive immunization against disseminated candidiasis was tested in mice with cyclophosphamide-induced neutropenia. Peptide-DC vaccines were given to mice prior to induction of neutropenia. We show active immunization with either Fba or Met6 peptide-DC vaccine significantly improved the survival and reduced the fungal burden of disseminated candidiasis in those immunocompromised mice. Importantly, we show that administration of two protective monoclonal antibodies also protect neutropenic mice against the disease, implying possibility of developing a successful passive immunotherapy strategy to treat the disease and protect against disseminated candidiasis. The results of this study are crucial as they address the fundamental questions as to whether the synthetic peptide vaccine induced immunity protects the host during a neutropenic episode. We anticipate that this peptide-vaccine study will serve as the foundation of future investigations into new peptide vaccines comprised of cell surface peptides from other medically important Candida species, as well as other fungi. PMID:26620842

Human cellular and humoral immune responses to Phlebotomus papatasi salivary gland antigens in endemic areas differing in prevalence of Leishmania major infection.

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Wafa Kammoun-Rebai

2017-10-01

Full Text Available Sand fly saliva compounds are able to elicit specific immune responses that have a significant role in Leishmania parasite establishment and disease outcome. Characterizing anti-saliva immune responses in individuals living in well defined leishmaniasis endemic areas would provide valuable insights regarding their effect on parasite transmission and establishment in humans.We explored the cellular and humoral immune responses to Phlebotomus (P. papatasi salivary gland extracts (SGE in individuals living in cutaneous leishmaniasis (CL old or emerging foci (OF, EF. OF was characterized by a higher infection prevalence as assessed by higher proportions of leishmanin skin test (LST positive individuals compared to EF. Subjects were further subdivided into healed, asymptomatic or naïve groups. We showed anti-SGE proliferation in less than 30% of the individuals, regardless of the immune status, in both foci. IFN-γ production was higher in OF and only observed in immune individuals from OF and naïve subjects from EF. Although IL-10 was not detected, addition of anti-human IL-10 antibodies revealed an increase in proliferation and IFN-γ production only in individuals from OF. The percentage of seropositive individuals was similar in immune and naïves groups but was significantly higher in OF. No correlation was observed between anti-saliva immune responses and LST response. High anti-SGE-IgG responses were associated with an increased risk of developing ZCL. No differences were observed for anti-SGE humoral or cellular responses among naïve individuals who converted or not their LST response or developed or not ZCL after the transmission season.These data suggest that individuals living in an old focus characterized by a frequent exposure to sand fly bites and a high prevalence of infection, develop higher anti-saliva IgG responses and IFN-γ levels and a skew towards a Th2-type cellular response, probably in favor of parasite establishment

Antiviral immunity in fish – functional analysis using DNA vaccination as a tool

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Lorenzen, Niels; Lorenzen, Ellen; Einer-Jensen, Katja

2013-01-01

fingerlings. Vaccination of fish at an early stage appears advantageous, since larger fish require higher doses of vaccine to be protected. Even in fish with an average size of 0.5 g at the time of vaccination, good protection can be obtained. Interestingly, immunity is established already a few days after...... and cellular components both play a role in the long lasting protection. The similarity of the functional immune response profile to that induced by a natural virus infection is striking and is most likely one of the major reasons for the efficacy of the rhabdovirus DNA vaccines. Although other elements like...... protein gene suggest that the structural requirements for antigenicity are different from the requirements for immunogenicity....

Intranasal boosting with an adenovirus-vectored vaccine markedly enhances protection by parenteral Mycobacterium bovis BCG immunization against pulmonary tuberculosis.

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Santosuosso, Michael; McCormick, Sarah; Zhang, Xizhong; Zganiacz, Anna; Xing, Zhou

2006-08-01

Parenterally administered Mycobacterium bovis BCG vaccine confers only limited immune protection from pulmonary tuberculosis in humans. There is a need for developing effective boosting vaccination strategies. We examined a heterologous prime-boost regimen utilizing BCG as a prime vaccine and our recently described adenoviral vector expressing Ag85A (AdAg85A) as a boost vaccine. Since we recently demonstrated that a single intranasal but not intramuscular immunization with AdAg85A was able to induce potent protection from pulmonary Mycobacterium tuberculosis challenge in a mouse model, we compared the protective effects of parenteral and mucosal booster immunizations following subcutaneous BCG priming. Protection by BCG prime immunization was not effectively boosted by subcutaneous BCG or intramuscular AdAg85A. In contrast, protection by BCG priming was remarkably boosted by intranasal AdAg85A. Such enhanced protection by intranasal AdAg85A was correlated to the numbers of gamma interferon-positive CD4 and CD8 T cells residing in the airway lumen of the lung. Our study demonstrates that intranasal administration of AdAg85A represents an effective way to boost immune protection by parenteral BCG vaccination.

Lessons Learned from Protective Immune Responses to Optimize Vaccines against Cryptosporidiosis

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Maxime W. Lemieux

2017-12-01

Full Text Available In developing countries, cryptosporidiosis causes moderate-to-severe diarrhea and kills thousands of infants and toddlers annually. Drinking and recreational water contaminated with Cryptosporidium spp. oocysts has led to waterborne outbreaks in developed countries. A competent immune system is necessary to clear this parasitic infection. A better understanding of the immune responses required to prevent or limit infection by this protozoan parasite is the cornerstone of development of an effective vaccine. In this light, lessons learned from previously developed vaccines against Cryptosporidium spp. are at the foundation for development of better next-generation vaccines. In this review, we summarize the immune responses elicited by naturally and experimentally-induced Cryptosporidium spp. infection and by several experimental vaccines in various animal models. Our aim is to increase awareness about the immune responses that underlie protection against cryptosporidiosis and to encourage promotion of these immune responses as a key strategy for vaccine development. Innate and mucosal immunity will be addressed as well as adaptive immunity, with an emphasis on the balance between TH1/TH2 immune responses. Development of more effective vaccines against cryptosporidiosis is needed to prevent Cryptosporidium spp.-related deaths in infants and toddlers in developing countries.

Inherent X-Linked Genetic Variability and Cellular Mosaicism Unique to Females Contribute to Sex-Related Differences in the Innate Immune Response

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Zoltan Spolarics

2017-11-01

Full Text Available Females have a longer lifespan and better general health than males. Considerable number of studies also demonstrated that, after trauma and sepsis, females present better outcomes as compared to males indicating sex-related differences in the innate immune response. The current notion is that differences in the immuno-modulatory effects of sex hormones are the underlying causative mechanism. However, the field remains controversial and the exclusive role of sex hormones has been challenged. Here, we propose that polymorphic X-linked immune competent genes, which are abundant in the population are important players in sex-based immuno-modulation and play a key role in causing sex-related outcome differences following trauma or sepsis. We describe the differences in X chromosome (ChrX regulation between males and females and its consequences in the context of common X-linked polymorphisms at the individual as well as population level. We also discuss the potential pathophysiological and immune-modulatory aspects of ChrX cellular mosaicism, which is unique to females and how this may contribute to sex-biased immune-modulation. The potential confounding effects of ChrX skewing of cell progenitors at the bone marrow is also presented together with aspects of acute trauma-induced de novo ChrX skewing at the periphery. In support of the hypothesis, novel observations indicating ChrX skewing in a female trauma cohort as well as case studies depicting the temporal relationship between trauma-induced cellular skewing and the clinical course are also described. Finally, we list and discuss a selected set of polymorphic X-linked genes, which are frequent in the population and have key regulatory or metabolic functions in the innate immune response and, therefore, are primary candidates for mediating sex-biased immune responses. We conclude that sex-related differences in a variety of disease processes including the innate inflammatory response to injury

Age and long-term protective immunity in dogs and cats.

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Schultz, R D; Thiel, B; Mukhtar, E; Sharp, P; Larson, L J

2010-01-01

Vaccination can provide an immune response that is similar in duration to that following a natural infection. In general, adaptive immunity to viruses develops earliest and is highly effective. Such anti-viral immune responses often result in the development of sterile immunity and the duration of immunity (DOI) is often lifelong. In contrast, adaptive immunity to bacteria, fungi or parasites develops more slowly and the DOI is generally short compared with most systemic viral infections. Sterile immunity to these infectious agents is less commonly engendered. Old dogs and cats rarely die from vaccine-preventable infectious disease, especially when they have been vaccinated and immunized as young adults (i.e. between 16 weeks and 1 year of age). However, young animals do die, often because vaccines were either not given or not given at an appropriate age (e.g. too early in life in the presence of maternally derived antibody [MDA]). More animals need to be vaccinated to increase herd (population) immunity. The present study examines the DOI for core viral vaccines in dogs that had not been revaccinated for as long as 9 years. These animals had serum antibody to canine distemper virus (CDV), canine parvovirus type 2 (CPV-2) and canine adenovirus type-1 (CAV-1) at levels considered protective and when challenged with these viruses, the dogs resisted infection and/or disease. Thus, even a single dose of modified live virus (MLV) canine core vaccines (against CDV, cav-2 and cpv-2) or MLV feline core vaccines (against feline parvovirus [FPV], feline calicivirus [FCV] and feline herpesvirus [FHV]), when administered at 16 weeks or older, could provide long-term immunity in a very high percentage of animals, while also increasing herd immunity. Copyright 2009 Elsevier Ltd. All rights reserved.

Cellular and humoral immune responses in a population from the Baringo District, Kenya to Leishmania promastigote lipophosphoglycan

DEFF Research Database (Denmark)

Kurtzhals, J A; Hey, A S; Theander, T G

1992-01-01

In a cross-sectional house-to-house study in a leishmaniasis-endemic area in Kenya, the cellular and humoral immune response to Leishmania lipophosphoglycan (LPG) was determined. Clinical data, peripheral blood mononuclear cells, and plasma were obtained from 50 individuals over the age of eight...

Immunization with influenza virus hemagglutinin globular region containing the receptor-binding pocket.

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Jeon, Sung Ho; Arnon, Ruth

2002-01-01

The globular region of hemagglutinin (residues 91-261) membrane glycoprotein of influenza virus that encompasses the binding zone to the oligosaccharide receptor of target cells has been cloned by reverse transcriptase-polymerase chain reaction (RT-PCR). This protein segment (denoted HA91-261 peptide) induced significant immune response in mice. The serum antibodies and lung homogenates from the immunized mice cross-reacted with native virus particles. The cellular immunity was manifested by proliferative splenocyte responses and cytokine release indicating T helper type 1 activity. The plasmid DNA containing this segment (denoted pHA91-261) provoked, in addition, a significant cytotoxic T lymphocyte (CTL) response, whereas the HA91-261 protein fragment led to no such response. Both the DNA and the protein fragment of HA91-261 induced significant protection against viral challenge, although the immune response they induce might be along different pathways. Interestingly, the combined DNA priming-protein boosting immunization regimen did not induce protection against viral challenges even though it led to significant humoral immune responses similar to that induced by the peptide vaccine.

New insights into innate immune control of systemic candidiasis

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Lionakis, Michail S.

2014-01-01

Systemic infection caused by Candida species is the fourth leading cause of nosocomial bloodstream infection in modern hospitals and carries high morbidity and mortality despite antifungal therapy. A recent surge of immunological studies in the mouse models of systemic candidiasis and the parallel discovery and phenotypic characterization of inherited genetic disorders in antifungal immune factors that are associated with enhanced susceptibility or resistance to the infection have provided new insights into the cellular and molecular basis of protective innate immune responses against Candida. In this review, the new developments in our understanding of how the mammalian immune system responds to systemic Candida challenge are synthesized and important future research directions are highlighted. PMID:25023483

Evaluation of cellular phenotypes implicated in immunopathogenesis and monitoring immune reconstitution inflammatory syndrome in HIV/leprosy cases.

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Giacoia-Gripp, Carmem Beatriz Wagner; Sales, Anna Maria; Nery, José Augusto da Costa; Santos-Oliveira, Joanna Reis; de Oliveira, Ariane Leite; Sarno, Euzenir Nunes; Morgado, Mariza Gonçalves

2011-01-01

It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR). However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%), dropping significantly (p<0,05) during post-IRIS/RR moments (median: 29,7%). Furthermore, an increase of cellular activation seems to occur prior to IRIS/RR. These data suggest CD38 expression in CD8+ T cells interesting tool identifying HIV/leprosy individuals at risk for IRIS/RR. So, a

Evaluation of cellular phenotypes implicated in immunopathogenesis and monitoring immune reconstitution inflammatory syndrome in HIV/leprosy cases.

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Carmem Beatriz Wagner Giacoia-Gripp

Full Text Available BACKGROUND: It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR. However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. METHODS/PRINCIPAL FINDINGS: Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%, dropping significantly (p<0,05 during post-IRIS/RR moments (median: 29,7%. Furthermore, an increase of cellular activation seems to occur prior to IRIS/RR. CONCLUSION/SIGNIFICANCE: These data suggest CD38 expression in CD8+ T cells

Transdermal influenza immunization with vaccine-coated microneedle arrays.

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Dimitrios G Koutsonanos

Full Text Available Influenza is a contagious disease caused by a pathogenic virus, with outbreaks all over the world and thousands of hospitalizations and deaths every year. Due to virus antigenic drift and short-lived immune responses, annual vaccination is required. However, vaccine coverage is incomplete, and improvement in immunization is needed. The objective of this study is to investigate a novel method for transdermal delivery using metal microneedle arrays (MN coated with inactivated influenza virus to determine whether this route is a simpler and safer approach than the conventional immunization, capable to induce robust immune responses and confer protection against lethal virus challenge.Inactivated A/Aichi/2/68 (H3N2 influenza virus was coated on metal microneedle arrays and applied to mice as a vaccine in the caudal dorsal skin area. Substantial antibody titers with hemagglutination inhibition activity were detected in sera collected two and four weeks after a single vaccine dose. Challenge studies in mice with 5 x LD(50 of mouse adapted Aichi virus demonstrated complete protection. Microneedle vaccination induced a broad spectrum of immune responses including CD4+ and CD8+ responses in the spleen and draining lymph node, a high frequency of antigen-secreting cells in the lung and induction of virus-specific memory B-cells. In addition, the use of MN showed a dose-sparing effect and a strong Th2 bias when compared to an intramuscular (IM reference immunization.The present results show that delivery of inactivated influenza virus through the skin using metal microneedle arrays induced strong humoral and cellular immune responses capable of conferring protection against virus challenge as efficiently as intramuscular immunization, which is the standard vaccination route. In view of the convenience of delivery and the potential for self-administration, vaccine-coated metal microneedles may provide a novel and highly effective immunization method.

Immunization with lipopolysaccharide-deficient whole cells provides protective immunity in an experimental mouse model of Acinetobacter baumannii infection.

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Meritxell García-Quintanilla

Full Text Available The increasing clinical importance of infections caused by multidrug resistant Acinetobacter baumannii warrants the development of novel approaches for prevention and treatment. In this context, vaccination of certain patient populations may contribute to reducing the morbidity and mortality caused by this pathogen. Vaccines against Gram-negative bacteria based on inactivated bacterial cells are highly immunogenic and have been shown to produce protective immunity against a number of bacterial species. However, the high endotoxin levels present in these vaccines due to the presence of lipopolysaccharide complicates their use in human vaccination. In the present study, we used a laboratory-derived strain of A. baumannii that completely lacks lipopolysaccharide due to a mutation in the lpxD gene (IB010, one of the genes involved in the first steps of lipopolysaccharide biosynthesis, for vaccination. We demonstrate that IB010 has greatly reduced endotoxin content (<1.0 endotoxin unit/106 cells compared to wild type cells. Immunization with formalin inactivated IB010 produced a robust antibody response consisting of both IgG1 and IgG2c subtypes. Mice immunized with IB010 had significantly lower post-infection tissue bacterial loads and significantly lower serum levels of the pro-inflammatory cytokines IL-1β, TNF-α and IL-6 compared to control mice in a mouse model of disseminated A. baumannii infection. Importantly, immunized mice were protected from infection with the ATCC 19606 strain and an A. baumannii clinical isolate. These data suggest that immunization with inactivated A. baumannii whole cells deficient in lipopolysaccharide could serve as the basis for a vaccine for the prevention of infection caused by A. baumannii.

Protective Immunity and Reduced Renal Colonization Induced by Vaccines Containing Recombinant Leptospira interrogans Outer Membrane Proteins and Flagellin Adjuvant

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Monaris, D.; Sbrogio-Almeida, M. E.; Dib, C. C.; Canhamero, T. A.; Souza, G. O.; Vasconcellos, S. A.; Ferreira, L. C. S.

2015-01-01

Leptospirosis is a global zoonotic disease caused by different Leptospira species, such as Leptospira interrogans, that colonize the renal tubules of wild and domestic animals. Thus far, attempts to develop effective leptospirosis vaccines, both for humans and animals, have failed to induce immune responses capable of conferring protection and simultaneously preventing renal colonization. In this study, we evaluated the protective immunity induced by subunit vaccines containing seven different recombinant Leptospira interrogans outer membrane proteins, including the carboxy-terminal portion of the immunoglobulinlike protein A (LigAC) and six novel antigens, combined with aluminum hydroxide (alum) or Salmonella flagellin (FliC) as adjuvants. Hamsters vaccinated with the different formulations elicited high antigen-specific antibody titers. Immunization with LigAC, either with alum or flagellin, conferred protective immunity but did not prevent renal colonization. Similarly, animals immunized with LigAC or LigAC coadministered with six leptospiral proteins with alum adjuvant conferred protection but did not reduce renal colonization. In contrast, immunizing animals with the pool of seven antigens in combination with flagellin conferred protection and significantly reduced renal colonization by the pathogen. The present study emphasizes the relevance of antigen composition and added adjuvant in the efficacy of antileptospirosis subunit vaccines and shows the complex relationship between immune responses and renal colonization by the pathogen. PMID:26108285

Protective effect of intranasal immunization with Neospora caninum membrane antigens against murine neosporosis established through the gastrointestinal tract

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Ferreirinha, Pedro; Dias, Joana; Correia, Alexandra; Pérez-Cabezas, Begoña; Santos, Carlos; Teixeira, Luzia; Ribeiro, Adília; Rocha, António; Vilanova, Manuel

2014-01-01

Neospora caninum is an Apicomplexa parasite that in the last two decades was acknowledged as the main pathogenic agent responsible for economic losses in the cattle industry. In the present study, the effectiveness of intranasal immunization with N. caninum membrane antigens plus CpG adjuvant was assessed in a murine model of intragastrically established neosporosis. Immunized mice presented a lower parasitic burden in the brain on infection with 5 × 107 tachyzoites, showing that significant protection was achieved by this immunization strategy. Intestinal IgA antibodies raised by immunization markedly agglutinated live N. caninum tachyzoites whereas previous opsonization with IgG antibodies purified from immunized mice sera reduced parasite survival within macrophage cells. Although an IgG1 : IgG2a ratio < 1 was detected in the immunized mice before and after infection, indicative of a predominant T helper type 1 immune response, no increased production of interferon-γ was detected in the spleen or mesenteric lymph nodes of the immunized mice. Altogether, these results show that mucosal immunization with N. caninum membrane proteins plus CpG adjuvant protect against intragastrically established neosporosis and indicate that parasite-specific mucosal and circulating antibodies have a protective role against this parasitic infection. PMID:24128071

Role of pro-inflammatory cytokine IL-17 in Leishmania pathogenesis and in protective immunity by Leishmania vaccines.

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Banerjee, Antara; Bhattacharya, Parna; Joshi, Amritanshu B; Ismail, Nevien; Dey, Ranadhir; Nakhasi, Hira L

2016-11-01

The clinical outcome of Leishmania pathogenesis ranges from active skin lesions to fatal visceral dissemination and severely impaired T cell immunity. It is well established that a strong Th1 immune response is protective against cutaneous forms of the disease, however a mixed Th1/Th2 response is most commonly observed against visceral infections as evident from previous studies. Aside from Th1/Th2 cytokines, the pro-inflammatory IL-17 cytokine family plays an important role in the clearance of intracellular pathogens. In Leishmania induced skin lesions, IL-17 produced by Th17 cells is shown to exacerbate the disease, suggesting a role in pathogenesis. However, a protective role for IL-17 is indicated by the expansion of IL-17 producing cells in vaccine-induced immunity. In human visceral leishmaniasis (VL) it has been demonstrated that IL-17 and IL-22 are associated with protection against re-exposure to Leishmania, which further suggests the involvement of IL-17 in vaccine induced protective immunity. Although there is no vaccine against any form of leishmaniasis, the development of genetically modified live attenuated parasites as vaccine candidates prove to be promising, as they successfully induce a robust protective immune response in various animal models. However, the role of IL-17 producing cells and Th17 cells in response to these vaccine candidates remains unexplored. In this article, we review the role of IL-17 in Leishmania pathogenesis and the potential impact on vaccine induced immunity, with a special focus on live attenuated Leishmania parasites. Published by Elsevier Inc.

Innate Immunity and Breast Milk.

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Cacho, Nicole Theresa; Lawrence, Robert M

2017-01-01

Human milk is a dynamic source of nutrients and bioactive factors; unique in providing for the human infant's optimal growth and development. The growing infant's immune system has a number of developmental immune deficiencies placing the infant at increased risk of infection. This review focuses on how human milk directly contributes to the infant's innate immunity. Remarkable new findings clarify the multifunctional nature of human milk bioactive components. New research techniques have expanded our understanding of the potential for human milk's effect on the infant that will never be possible with milk formulas. Human milk microbiome directly shapes the infant's intestinal microbiome, while the human milk oligosaccharides drive the growth of these microbes within the gut. New techniques such as genomics, metabolomics, proteomics, and glycomics are being used to describe this symbiotic relationship. An expanded role for antimicrobial proteins/peptides within human milk in innate immune protection is described. The unique milieu of enhanced immune protection with diminished inflammation results from a complex interaction of anti-inflammatory and antioxidative factors provided by human milk to the intestine. New data support the concept of mucosal-associated lymphoid tissue and its contribution to the cellular content of human milk. Human milk stem cells (hMSCs) have recently been discovered. Their direct role in the infant for repair and regeneration is being investigated. The existence of these hMSCs could prove to be an easily harvested source of multilineage stem cells for the study of cancer and tissue regeneration. As the infant's gastrointestinal tract and immune system develop, there is a comparable transition in human milk over time to provide fewer immune factors and more calories and nutrients for growth. Each of these new findings opens the door to future studies of human milk and its effect on the innate immune system and the developing infant.

Yeast-expressed recombinant As16 protects mice against Ascaris suum infection through induction of a Th2-skewed immune response.

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Junfei Wei

2017-07-01

Full Text Available Ascariasis remains the most common helminth infection in humans. As an alternative or complementary approach to global deworming, a pan-anthelminthic vaccine is under development targeting Ascaris, hookworm, and Trichuris infections. As16 and As14 have previously been described as two genetically related proteins from Ascaris suum that induced protective immunity in mice when formulated with cholera toxin B subunit (CTB as an adjuvant, but the exact protective mechanism was not well understood.As16 and As14 were highly expressed as soluble recombinant proteins (rAs16 and rAs14 in Pichia pastoris. The yeast-expressed rAs16 was highly recognized by immune sera from mice infected with A. suum eggs and elicited 99.6% protection against A. suum re-infection. Mice immunized with rAs16 formulated with ISA720 displayed significant larva reduction (36.7% and stunted larval development against A. suum eggs challenge. The protective immunity was associated with a predominant Th2-type response characterized by high titers of serological IgG1 (IgG1/IgG2a > 2000 and high levels of IL-4 and IL-5 produced by restimulated splenocytes. A similar level of protection was observed in mice immunized with rAs16 formulated with alum (Alhydrogel, known to induce mainly a Th2-type immune response, whereas mice immunized with rAs16 formulated with MPLA or AddaVax, both known to induce a Th1-type biased response, were not significantly protected against A. suum infection. The rAs14 protein was not recognized by A. suum infected mouse sera and mice immunized with rAs14 formulated with ISA720 did not show significant protection against challenge infection, possibly due to the protein's inaccessibility to the host immune system or a Th1-type response was induced which would counter a protective Th2-type response.Yeast-expressed rAs16 formulated with ISA720 or alum induced significant protection in mice against A. suum egg challenge that associates with a Th2-skewed immune

Evaluation of Cellular Phenotypes Implicated in Immunopathogenesis and Monitoring Immune Reconstitution Inflammatory Syndrome in HIV/Leprosy Cases

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Giacoia-Gripp, Carmem Beatriz Wagner; Sales, Anna Maria; Nery, José Augusto da Costa; Santos-Oliveira, Joanna Reis; de Oliveira, Ariane Leite; Sarno, Euzenir Nunes; Morgado, Mariza Gonçalves

2011-01-01

Background It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR). However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. Methods/Principal Findings Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%), dropping significantly (pleprosy individuals at risk for IRIS/RR. So, a comparative investigation to leprosy patients at RR should be conducted. PMID:22205964

CELLULAR VACCINES IN LISTERIOSIS: ROLE OF THE LISTERIA ANTIGEN GAPDH.

Directory of Open Access Journals (Sweden)

Ricardo eCalderon-Gonzalez

2014-02-01

Full Text Available The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH, and several epitopes such as the LLO peptides, LLO189–201 and LLO91–99 and the GAPDH peptide, GAPDH1–22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1–22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91–99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1–22-specific CD4+ and CD8+ immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4+ and CD8+ epitopes.

Cellular vaccines in listeriosis: role of the Listeria antigen GAPDH

Science.gov (United States)

Calderón-González, Ricardo; Frande-Cabanes, Elisabet; Bronchalo-Vicente, Lucía; Lecea-Cuello, M. Jesús; Pareja, Eduardo; Bosch-Martínez, Alexandre; Fanarraga, Mónica L.; Yañez-Díaz, Sonsoles; Carrasco-Marín, Eugenio; Álvarez-Domínguez, Carmen

2014-01-01

The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs) and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO) and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and several epitopes such as the LLO peptides, LLO189−201 and LLO91−99 and the GAPDH peptide, GAPDH1−22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1−22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91−99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1−22-specific CD4+ and CD8+ immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4+ and CD8+ epitopes. PMID:24600592

Induction of protective immune responses in mice by double DNA ...

African Journals Online (AJOL)

Purpose: To investigate the efficacy of a double DNA vaccine encoding of Brucella melitensis omp31 gene and of Escherichia coli eae gene in inducing protective immune response in a mouse model. Methods: After performing PCR assays and cloning both the eae and omp31 genes, the generated DNA vaccines were ...

Total Leishmania antigens with Poly(I:C) induce Th1 protective response.

Science.gov (United States)

Sanchez, M V; Eliçabe, R J; Di Genaro, M S; Germanó, M J; Gea, S; García Bustos, M F; Salomón, M C; Scodeller, E A; Cargnelutti, D E

2017-11-01

Our proposal was to develop a vaccine based on total Leishmania antigens (TLA) adjuvanted with polyinosinic-polycytidylic acid [Poly(I:C)] able to induce a Th1 response which can provide protection against Leishmania infection. Mice were vaccinated with two doses of TLA-Poly(I:C) administered by subcutaneous route at 3-week interval. Humoral and cellular immune responses induced by the immunization were measured. The protective efficacy of the vaccine was evaluated by challenging mice with infective promastigotes of Leishmania (Leishmania) amazonensis into the footpad. Mice vaccinated with TLA-Poly(I:C) showed a high anti-Leishmania IgG titre, as well as increased IgG1 and IgG2a subclass titres compared with mice vaccinated with the TLA alone. The high IgG2a indicated a Th1 bias response induced by the TLA-Poly(I:C) immunization. Accordingly, the cellular immune response elicited by the formulation was characterized by an increased production of IFN-γ and no significant production of IL-4. The TLA-Poly(I:C) immunization elicited good protection, which was associated with decreased footpad swelling, a lower parasite load and a reduced histopathological alteration in the footpad. Our findings demonstrate a promising vaccine against cutaneous leishmaniasis that is relatively economic and easy to develop and which should be taken into account for preventing leishmaniasis in developing countries. © 2017 John Wiley & Sons Ltd.

Studies on the protection effects of functional foods for skin immune system from radiation damage

International Nuclear Information System (INIS)

Yee, Sung Tae; Shin, Seong Hae; Kim, Do Sun; Heo, Ji Yun; Kang, Hye In

2007-07-01

We evaluated the protective effects of pilot products (HemoHIM and HemoTonic) on the UV-induced skin immune damages as the following. · Protective effects of HemoHIM and HemoTonic against UV using contact hypersensitivity model - Protection against depression of contact hypersensitivity by administration and skin application of HemoHIM and HemoTonic - Induction of dendritic cell differentiation and maturation by HemoHIM and HemoTonic treatment - Improvement of antigen-presenting activity of dedritic cells by HemoHIM and HemoTonic treatment · Protective effects of HemoHIM and HemoTonic on skin immune system against UV-irradiation - Protection of antigen-presenting activity of dendritic cells under UV-irradiation - In vivo protection of antigen-presenting activity of Langerhans cells in UV-irradiated mice · Protective effects of HemoHIM on UV-induced apoptosis of dendritic cells - Inhibition of cell membrane change, mitochondrial potential change, SubG1 cell population, nuclear condensation, and DNA fragmentation in UV-irradiated dendritic cells · Anti-allergic effects of HemoHIM and HemoTonic in human adipocyte HMC-1 cells - Inhibition of allergic histamine release from adipocytes - Inhibition of secretion of inflammatory cytokines (IL-6, IL-8, TNF-α, GM-CSF) - Inhibition of c-kit, tryptase, FcεRI mRNA expression From these results, the developed functional food products (HemoHIM, HemoTonic) showed the protection and recovery of the immune functions in the UV-irradiated skin. It is suggested that these products may be used as a new functional food or cosmetic material for the protection of skin damage and the promotion of recovery

Protective MCMV immunity by vaccination of the salivary gland via Wharton's duct: replication-deficient recombinant adenovirus expressing individual MCMV genes elicits protection similar to that of MCMV.

Science.gov (United States)

Liu, Guangliang; Zhang, Fangfang; Wang, Ruixue; London, Lucille; London, Steven D

2014-04-01

Salivary glands, a major component of the mucosal immune system, confer antigen-specific immunity to mucosally acquired pathogens. We investigated whether a physiological route of inoculation and a subunit vaccine approach elicited MCMV-specific and protective immunity. Mice were inoculated by retrograde perfusion of the submandibular salivary glands via Wharton's duct with tcMCMV or MCMV proteins focused to the salivary gland via replication-deficient adenovirus expressing individual MCMV genes (gB, gH, IE1; controls: saline and replication deficient adenovirus without MCMV inserts). Mice were evaluated for MCMV-specific antibodies, T-cell responses, germinal center formation, and protection against a lethal MCMV challenge. Retrograde perfusion with tcMCMV or adenovirus expressed MCMV proteins induced a 2- to 6-fold increase in systemic and mucosal MCMV-specific antibodies, a 3- to 6-fold increase in GC marker expression, and protection against a lethal systemic challenge, as evidenced by up to 80% increased survival, decreased splenic pathology, and decreased viral titers from 10(6) pfu to undetectable levels. Thus, a focused salivary gland immunization via a physiological route with a protein antigen induced systemic and mucosal protective immune responses. Therefore, salivary gland immunization can serve as an alternative mucosal route for administering vaccines, which is directly applicable for use in humans.

Subunit Rotavirus Vaccine Administered Parenterally to Rabbits Induces Active Protective Immunity

Science.gov (United States)

Ciarlet, Max; Crawford, Sue E.; Barone, Christopher; Bertolotti-Ciarlet, Andrea; Ramig, Robert F.; Estes, Mary K.; Conner, Margaret E.

1998-01-01

Virus-like particles (VLPs) are being evaluated as a candidate rotavirus vaccine. The immunogenicity and protective efficacy of different formulations of VLPs administered parenterally to rabbits were tested. Two doses of VLPs (2/6-, G3 2/6/7-, or P[2], G3 2/4/6/7-VLPs) or SA11 simian rotavirus in Freund’s adjuvants, QS-21 (saponin adjuvant), or aluminum phosphate (AlP) were administered. Serological and mucosal immune responses were evaluated in all vaccinated and control rabbits before and after oral challenge with 103 50% infective doses of live P[14], G3 ALA lapine rotavirus. All VLP- and SA11-vaccinated rabbits developed high levels of rotavirus-specific serum and intestinal immunoglobulin G (IgG) antibodies but not intestinal IgA antibodies. SA11 and 2/4/6/7-VLPs afforded similar but much higher mean levels of protection than 2/6/7- or 2/6-VLPs in QS-21. The presence of neutralizing antibodies to VP4 correlated (P < 0.001, r = 0.55; Pearson’s correlation coefficient) with enhanced protection rates, suggesting that these antibodies are important for protection. Although the inclusion of VP4 resulted in higher mean protection levels, high levels of protection (87 to 100%) from infection were observed in individual rabbits immunized with 2/6/7- or 2/6-VLPs in Freund’s adjuvants. Therefore, neither VP7 nor VP4 was absolutely required to achieve protection from infection in the rabbit model when Freund’s adjuvant was used. Our results show that VLPs are immunogenic when administered parenterally to rabbits and that Freund’s adjuvant is a better adjuvant than QS-21. The use of the rabbit model may help further our understanding of the critical rotavirus proteins needed to induce active protection. VLPs are a promising candidate for a parenterally administered subunit rotavirus vaccine. PMID:9765471

Cellular stress induces a protective sleep-like state in C. elegans.

Science.gov (United States)

Hill, Andrew J; Mansfield, Richard; Lopez, Jessie M N G; Raizen, David M; Van Buskirk, Cheryl

2014-10-20

Sleep is recognized to be ancient in origin, with vertebrates and invertebrates experiencing behaviorally quiescent states that are regulated by conserved genetic mechanisms. Despite its conservation throughout phylogeny, the function of sleep remains debated. Hypotheses for the purpose of sleep include nervous-system-specific functions such as modulation of synaptic strength and clearance of metabolites from the brain, as well as more generalized cellular functions such as energy conservation and macromolecule biosynthesis. These models are supported by the identification of synaptic and metabolic processes that are perturbed during prolonged wakefulness. It remains to be seen whether perturbations of cellular homeostasis in turn drive sleep. Here we show that under conditions of cellular stress, including noxious heat, cold, hypertonicity, and tissue damage, the nematode Caenorhabditis elegans engages a behavioral quiescence program. The stress-induced quiescent state displays properties of sleep and is dependent on the ALA neuron, which mediates the conserved soporific effect of epidermal growth factor (EGF) ligand overexpression. We characterize heat-induced quiescence in detail and show that it is indeed dependent on components of EGF signaling, providing physiological relevance to the behavioral effects of EGF family ligands. We find that after noxious heat exposure, quiescence-defective animals show elevated expression of cellular stress reporter genes and are impaired for survival, demonstrating the benefit of stress-induced behavioral quiescence. These data provide evidence that cellular stress can induce a protective sleep-like state in C. elegans and suggest that a deeply conserved function of sleep is to mitigate disruptions of cellular homeostasis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Humoral and cellular immune response in mice induced by the classical swine fever virus E2 protein fused to the porcine CD154 antigen.

Science.gov (United States)

Sordo, Yusmel; Suárez, Marisela; Caraballo, Rosalina; Sardina, Talía; Brown, Emma; Duarte, Carlos; Lugo, Joanna; Gil, Lázaro; Perez, Danny; Oliva, Ayme; Vargas, Milagros; Santana, Elaine; Valdés, Rodolfo; Rodríguez, María Pilar

2018-03-01

The development of subunit vaccines against classical swine fever is a desirable goal, because it allows discrimination between vaccinated and infected animals. In this study, humoral and cellular immune response elicited in inbred BALB/c mice by immunization with a recombinant classical swine fever virus (CSFV) E2 protein fused to porcine CD154 antigen (E2CD154) was assessed. This model was used as a predictor of immune response in swine. Mice were immunized with E2CD154 emulsified in Montanide ISA50V2 or dissolved in saline on days 1 and 21. Another group received E2His antigen, without CD154, in the same adjuvant. Montanide ISA50V2 or saline served as negative controls for each experimental group. Animals immunized with 12.5 and 2.5 μg/dose of E2CD154 developed the highest titers (>1:2000) of CSFV neutralizing antibodies. Moreover, CSFV specific splenocyte gamma-interferon production, measured after seven and twenty-eight days of immunization, was significantly higher in mice immunized with 12.5 μg of E2CD154. As a conclusion, E2CD154 emulsified in Montanide ISA50 V2 was able to induce a potent humoral and an early cellular immune response in inbred BALB/c mice. Therefore, this immunogen might be an appropriate candidate to elicit immune response in swine, control CSF disease and to eliminate CSFV in swine. Copyright © 2018 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

A single immunization with a recombinant canine adenovirus expressing the rabies virus G protein confers protective immunity against rabies in mice

International Nuclear Information System (INIS)

Li Jianwei; Faber, Milosz; Papaneri, Amy; Faber, Marie-Luise; McGettigan, James P.; Schnell, Matthias J.; Dietzschold, Bernhard

2006-01-01

Rabies vaccines based on live attenuated rabies viruses or recombinant pox viruses expressing the rabies virus (RV) glycoprotein (G) hold the greatest promise of safety and efficacy, particularly for oral immunization of wildlife. However, while these vaccines induce protective immunity in foxes, they are less effective in other animals, and safety concerns have been raised for some of these vaccines. Because canine adenovirus 2 (CAV2) is licensed for use as a live vaccine for dogs and has an excellent efficacy and safety record, we used this virus as an expression vector for the RVG. The recombinant CAV2-RV G produces virus titers similar to those produced by wild-type CAV2, indicating that the RVG gene does not affect virus replication. Comparison of RVG expressed by CAV2-RV G with that of vaccinia-RV G recombinant virus (V-RG) revealed similar amounts of RV G on the cell surface. A single intramuscular or intranasal immunization of mice with CAV2-RVG induced protective immunity in a dose-dependent manner, with no clinical signs or discomfort from the virus infection regardless of the route of administration or the amount of virus

Early infections by myxoma virus of young rabbits (Oryctolagus cuniculus) protected by maternal antibodies activate their immune system and enhance herd immunity in wild populations.

Science.gov (United States)

Marchandeau, Stéphane; Pontier, Dominique; Guitton, Jean-Sébastien; Letty, Jérôme; Fouchet, David; Aubineau, Jacky; Berger, Francis; Léonard, Yves; Roobrouck, Alain; Gelfi, Jacqueline; Peralta, Brigitte; Bertagnoli, Stéphane

2014-03-04

The role of maternal antibodies is to protect newborns against acute early infection by pathogens. This can be achieved either by preventing any infection or by allowing attenuated infections associated with activation of the immune system, the two strategies being based on different cost/benefit ratios. We carried out an epidemiological survey of myxomatosis, which is a highly lethal infectious disease, in two distant wild populations of rabbits to describe the epidemiological pattern of the disease. Detection of specific IgM and IgG enabled us to describe the pattern of immunity. We show that maternal immunity attenuates early infection of juveniles and enables activation of their immune system. This mechanism associated with steady circulation of the myxoma virus in both populations, which induces frequent reinfections of immune rabbits, leads to the maintenance of high immunity levels within populations. Thus, myxomatosis has a low impact, with most infections being asymptomatic. This work shows that infection of young rabbits protected by maternal antibodies induces attenuated disease and activates their immune system. This may play a major role in reducing the impact of a highly lethal disease when ecological conditions enable permanent circulation of the pathogen.

Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model.

Science.gov (United States)

Carlson, Jolene; O'Donnell, Vivian; Alfano, Marialexia; Velazquez Salinas, Lauro; Holinka, Lauren G; Krug, Peter W; Gladue, Douglas P; Higgs, Stephen; Borca, Manuel V

2016-10-22

African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV). There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4) virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi) showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN)-γ responses, or specific cytokine profiles) and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

Salmonella enterica serovar Typhimurium lacking hfq gene confers protective immunity against murine typhoid.

Directory of Open Access Journals (Sweden)

Uday Shankar Allam

Full Text Available Salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. The emergence of multidrug-resistant strains of Salmonella leading to increased morbidity and mortality has further complicated its management. Live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. Of the various strategies used for the generation of live attenuated vaccine strains, focus has gradually shifted towards manipulation of virulence regulator genes. Hfq is a RNA chaperon which mediates the binding of small RNAs to the mRNA and assists in post-transcriptional gene regulation in bacteria. In this study, we evaluated the efficacy of the Salmonella Typhimurium Δhfq strain as a candidate for live oral vaccine in murine model of typhoid fever. Salmonella hfq deletion mutant is highly attenuated in cell culture and animal model implying a significant role of Hfq in bacterial virulence. Oral immunization with the Salmonella hfq deletion mutant efficiently protects mice against subsequent oral challenge with virulent strain of Salmonella Typhimurium. Moreover, protection was induced upon both multiple as well as single dose of immunizations. The vaccine strain appears to be safe for use in pregnant mice and the protection is mediated by the increase in the number of CD4(+ T lymphocytes upon vaccination. The levels of serum IgG and secretory-IgA in intestinal washes specific to lipopolysaccharide and outer membrane protein were significantly increased upon vaccination. Furthermore, hfq deletion mutant showed enhanced antigen presentation by dendritic cells compared to the wild type strain. Taken together, the studies in murine immunization model suggest that the Salmonella hfq deletion mutant can be a novel live oral vaccine candidate.

Artery Tertiary Lymphoid Organs Control Aorta Immunity and Protect against Atherosclerosis via Vascular Smooth Muscle Cell Lymphotoxin β Receptors

Science.gov (United States)

Hu, Desheng; Mohanta, Sarajo K.; Yin, Changjun; Peng, Li; Ma, Zhe; Srikakulapu, Prasad; Grassia, Gianluca; MacRitchie, Neil; Dever, Gary; Gordon, Peter; Burton, Francis L.; Ialenti, Armando; Sabir, Suleman R.; McInnes, Iain B.; Brewer, James M.; Garside, Paul; Weber, Christian; Lehmann, Thomas; Teupser, Daniel; Habenicht, Livia; Beer, Michael; Grabner, Rolf; Maffia, Pasquale; Weih, Falk; Habenicht, Andreas J.R.

2015-01-01

Summary Tertiary lymphoid organs (TLOs) emerge during nonresolving peripheral inflammation, but their impact on disease progression remains unknown. We have found in aged Apoe−/− mice that artery TLOs (ATLOs) controlled highly territorialized aorta T cell responses. ATLOs promoted T cell recruitment, primed CD4+ T cells, generated CD4+, CD8+, T regulatory (Treg) effector and central memory cells, converted naive CD4+ T cells into induced Treg cells, and presented antigen by an unusual set of dendritic cells and B cells. Meanwhile, vascular smooth muscle cell lymphotoxin β receptors (VSMC-LTβRs) protected against atherosclerosis by maintaining structure, cellularity, and size of ATLOs though VSMC-LTβRs did not affect secondary lymphoid organs: Atherosclerosis was markedly exacerbated in Apoe−/−Ltbr−/− and to a similar extent in aged Apoe−/−Ltbrfl/flTagln-cre mice. These data support the conclusion that the immune system employs ATLOs to organize aorta T cell homeostasis during aging and that VSMC-LTβRs participate in atherosclerosis protection via ATLOs. PMID:26084025

Can VHS virus bypass the protective immunity induced by DNA vaccination in rainbow trout?

DEFF Research Database (Denmark)

Sepúlveda, Dagoberto; Lorenzen, Niels

2016-01-01

DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability...... and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly...... pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus...

Long-Term Protective Immune Response Elicited by Vaccination with an Expression Genomic Library of Toxoplasma gondii

OpenAIRE

Fachado, Alberto; Rodriguez, Alexandro; Molina, Judith; Silvério, Jaline C.; Marino, Ana P. M. P.; Pinto, Luzia M. O.; Angel, Sergio O.; Infante, Juan F.; Traub-Cseko, Yara; Amendoeira, Regina R.; Lannes-Vieira, Joseli

2003-01-01

Immunization of BALB/c mice with an expression genomic library of Toxoplasma gondii induces a Th1-type immune response, with recognition of several T. gondii proteins (21 to 117 kDa) and long-term protective immunity against a lethal challenge. These results support further investigations to achieve a multicomponent anti-T. gondii DNA vaccine.

Immunization with LJM11 salivary protein protects against infection with Leishmania braziliensis in the presence of Lutzomyia longipalpis saliva.

Science.gov (United States)

Cunha, Jurema M; Abbehusen, Melissa; Suarez, Martha; Valenzuela, Jesus; Teixeira, Clarissa R; Brodskyn, Cláudia I

2018-01-01

Leishmania is transmitted in the presence of sand fly saliva. Protective immunity generated by saliva has encouraged identification of a vector salivary-based vaccine. Previous studies have shown that immunization with LJM11, a salivary protein from Lutzomyia longipalpis, is able to induce a Th1 immune response and protect mice against bites of Leishmania major-infected Lutzomyia longipalpis. Here, we further investigate if immunization with LJM11 recombinant protein is able to confer cross-protection against infection with Leishmania braziliensis associated with salivary gland sonicate (SGS) from Lutzomyia intermedia or Lu. longipalpis. Mice immunized with LJM11 protein exhibited an increased production of anti-LJM11 IgG, IgG1 and IgG2a and a DTH response characterized by an inflammatory infiltrate with the presence of CD4 + IFN-γ + T cells. LJM11-immunized mice were intradermally infected in the ear with L. braziliensis in the presence of Lu. longipalpis or Lu. intermedia SGS. A significant reduction of parasite numbers in the ear and lymph node in the group challenged with L. braziliensis plus Lu. longipalpis SGS was observed, but not when the challenge was performed with L. braziliensis plus Lu. intermedia SGS. A higher specific production of IFN-γ and absence of IL-10 by lymph node cells were only observed in LJM11 immunized mice after infection. After two weeks, a similar frequency of CD4 + IFN-γ + T cells was detected in LJM11 and BSA groups challenged with L. braziliensis plus Lu. longipalpis SGS, suggesting that early events possibly triggered by immunization are essential for protection against Leishmania infection. Our findings support the specificity of saliva-mediated immune responses and reinforce the importance of identifying cross-protective salivary antigens. Copyright © 2017 Elsevier B.V. All rights reserved.

Social network architecture of human immune cells unveiled by quantitative proteomics.

Science.gov (United States)

Rieckmann, Jan C; Geiger, Roger; Hornburg, Daniel; Wolf, Tobias; Kveler, Ksenya; Jarrossay, David; Sallusto, Federica; Shen-Orr, Shai S; Lanzavecchia, Antonio; Mann, Matthias; Meissner, Felix

2017-05-01

The immune system is unique in its dynamic interplay between numerous cell types. However, a system-wide view of how immune cells communicate to protect against disease has not yet been established. We applied high-resolution mass-spectrometry-based proteomics to characterize 28 primary human hematopoietic cell populations in steady and activated states at a depth of >10,000 proteins in total. Protein copy numbers revealed a specialization of immune cells for ligand and receptor expression, thereby connecting distinct immune functions. By integrating total and secreted proteomes, we discovered fundamental intercellular communication structures and previously unknown connections between cell types. Our publicly accessible (http://www.immprot.org/) proteomic resource provides a framework for the orchestration of cellular interplay and a reference for altered communication associated with pathology.

Studies on the protection effects of functional foods for skin immune system from radiation damage

Energy Technology Data Exchange (ETDEWEB)

Yee, Sung Tae; Shin, Seong Hae; Kim, Do Sun; Heo, Ji Yun; Kang, Hye In [Sunchon National University, Sunchon (Korea, Republic of)

2007-07-15

We evaluated the protective effects of pilot products (HemoHIM and HemoTonic) on the UV-induced skin immune damages as the following. centre dot Protective effects of HemoHIM and HemoTonic against UV using contact hypersensitivity model - Protection against depression of contact hypersensitivity by administration and skin application of HemoHIM and HemoTonic - Induction of dendritic cell differentiation and maturation by HemoHIM and HemoTonic treatment - Improvement of antigen-presenting activity of dedritic cells by HemoHIM and HemoTonic treatment centre dot Protective effects of HemoHIM and HemoTonic on skin immune system against UV-irradiation - Protection of antigen-presenting activity of dendritic cells under UV-irradiation - In vivo protection of antigen-presenting activity of Langerhans cells in UV-irradiated mice centre dot Protective effects of HemoHIM on UV-induced apoptosis of dendritic cells - Inhibition of cell membrane change, mitochondrial potential change, SubG1 cell population, nuclear condensation, and DNA fragmentation in UV-irradiated dendritic cells centre dot Anti-allergic effects of HemoHIM and HemoTonic in human adipocyte HMC-1 cells - Inhibition of allergic histamine release from adipocytes - Inhibition of secretion of inflammatory cytokines (IL-6, IL-8, TNF-alpha, GM-CSF) - Inhibition of c-kit, tryptase, FcepsilonRI mRNA expression From these results, the developed functional food products (HemoHIM, HemoTonic) showed the protection and recovery of the immune functions in the UV-irradiated skin. It is suggested that these products may be used as a new functional food or cosmetic material for the protection of skin damage and the promotion of recovery

Protection against avian metapneumovirus subtype C in turkeys immunized via the respiratory tract with inactivated virus.

Science.gov (United States)

Cha, Ra Mi; Khatri, Mahesh; Sharma, Jagdev M

2011-01-10

Avian metapneumovirus subtype C (aMPV/C) causes a severe upper respiratory tract (URT) infection in turkeys. Turkeys were inoculated oculonasally with inactivated aMPV/C adjuvanted with synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid (Poly IC). Immunized turkeys had elevated numbers of mucosal IgA+ cells in the URT and increased levels of virus-specific IgG and IgA in the lachrymal fluid and IgG in the serum. After 7 or 21 days post immunization, turkeys were challenged oculonasally with pathogenic aMPV/C. Immunized groups were protected against respiratory lesions induced by the challenge virus. Further, the viral copy number of the challenge virus in the URT were significantly lower in the immunized turkeys than in the unimmunized turkeys (P<0.05). These results showed that inactivated aMPV/C administered by the respiratory route induced protective immunity against pathogenic virus challenge. Copyright © 2010 Elsevier Ltd. All rights reserved.

A prime-boost vaccination strategy using attenuated Salmonella typhimurium and a replication-deficient recombinant adenovirus vector elicits protective immunity against human respiratory syncytial virus.

Science.gov (United States)

Fu, Yuan-Hui; He, Jin-Sheng; Wang, Xiao-Bo; Zheng, Xian-Xian; Wu, Qiang; Xie, Can; Zhang, Mei; Wei, Wei; Tang, Qian; Song, Jing-Dong; Qu, Jian-Guo; Hong, Tao

2010-04-23

Human respiratory syncytial virus (RSV), for which no clinically approved vaccine is available yet, is globally a serious pediatric pathogen of the lower respiratory tract. Several approaches have been used to develop vaccines against RSV, but none of these have been approved for use in humans. An efficient vaccine-enhancing strategy for RSV is still urgently needed. We found previously that oral SL7207/pcDNA3.1/F and intranasal FGAd/F were able to induce an effective protective immune response against RSV. The heterologous prime-boost immunization regime has been reported recently to be an efficient vaccine-enhancing strategy. Therefore, we investigated the ability of an oral SL7207/pcDNA3.1/F prime and intranasal (i.n.) FGAd/F boost regimen to generate immune responses to RSV. The SL7207/pcDNA3.1/F prime-FGAd/F boost regimen generated stronger RSV-specific humoral and mucosal immune responses in BALB/c mice than the oral SL7207/pcDNA3.1/F regimen alone, and stronger specific cellular immune responses than the i.n. FGAd/F regimen alone. Histopathological analysis showed an increased efficacy against RSV challenge by the heterologous prime-boost regimen. These results suggest that such a heterologous prime-boost strategy can enhance the efficacy of either the SL7207 or the FGAd vector regimen in generating immune responses in BALB/c mice. 2010 Elsevier Inc. All rights reserved.

Effect of cytokine-encoding plasmid delivery on immune response to Japanese encephalitis virus DNA vaccine in mice.

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Bharati, Kaushik; Appaiahgari, Mohan Babu; Vrati, Sudhanshu

2005-01-01

We have previously shown that immunization of mice with plasmid pMEa synthesizing Japanese encephalitis virus (JEV) envelope protein induced anti-JEV humoral and cellular immune responses. We now show that intra-muscular co-administration of mice with pMEa and pGM-CSF, encoding murine granulocyte-macrophage colony-stimulating factor or pIL-2, encoding murine interleukin-2 given 4 days after pMEa, augmented anti-JEV antibody titers. This did not enhance the level of protection in immunized mice against JEV. However, intra-dermal co-administration of pMEa and pGM-CSF in mice using the gene gun, enhanced anti-JEV antibody titers resulting in an increased level of protection in mice against lethal JEV challenge.

Development of monoclonal antibodies (MAbs) to feline interferon (fIFN)-γ as tools to evaluate cellular immune responses to feline infectious peritonitis virus (FIPV).

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Satoh, Ryoichi; Kaku, Ayumi; Satomura, Megumi; Kohori, Michiyo; Noura, Kanako; Furukawa, Tomoko; Kotake, Masako; Takano, Tomomi; Hohdatsu, Tsutomu

2011-06-01

Feline infectious peritonitis virus (FIPV) can cause a lethal disease in cats, feline infectious peritonitis (FIP). The antibody-dependent enhancement (ADE) of FIPV infection has been recognised in experimentally infected cats, and cellular immunity is considered to play an important role in preventing the onset of FIP. To evaluate the importance of cellular immunity for FIPV infection, monoclonal antibodies (MAbs) against feline interferon (fIFN)-γ were first created to establish fIFN-γ detection systems using the MAbs. Six anti-fIFN-γ MAbs were created. Then, the difference in epitope which those MAbs recognise was demonstrated by competitive enzyme-linked immunosorbent assay (ELISA) and IFN-γ neutralisation tests. Detection systems for fIFN-γ (sandwich ELISA, ELISpot assay, and two-colour flow cytometry) were established using anti-fIFN-γ MAbs that recognise different epitopes. In all tests, fIFN-γ production from peripheral blood mononuclear cells (PBMCs) obtained from cats experimentally infected with an FIPV isolate that did not develop the disease was significantly increased by heat-inactivated FIPV stimulation in comparison with medium alone. Especially, CD8(+)fIFN-γ(+) cells, but not CD4(+)fIFN-γ(+) cells, were increased. In contrast, fIFN-γ production from PBMCs isolated from cats that had developed FIP and specific pathogen-free (SPF) cats was not increased by heat-inactivated FIPV stimulation. These results suggest that cellular immunity plays an important role in preventing the development of FIP. Measurement of fIFN-γ production with the anti-fIFN-γ MAbs created in this study appeared to be useful in evaluating cellular immunity in cats. Copyright © 2011 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

Replicating Rather than Nonreplicating Adenovirus-Human Immunodeficiency Virus Recombinant Vaccines Are Better at Eliciting Potent Cellular Immunity and Priming High-Titer Antibodies

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Peng, Bo; Wang, Liqun Rejean; Gómez-Román, Victor Raúl; Davis-Warren, Alberta; Montefiori, David C.; Kalyanaraman, V. S.; Venzon, David; Zhao, Jun; Kan, Elaine; Rowell, Thomas J.; Murthy, Krishna K.; Srivastava, Indresh; Barnett, Susan W.; Robert-Guroff, Marjorie

2005-01-01

A major challenge in combating the human immunodeficiency virus (HIV) epidemic is the development of vaccines capable of inducing potent, persistent cellular immunity and broadly reactive neutralizing antibody responses to HIV type 1 (HIV-1). We report here the results of a preclinical trial using the chimpanzee model to investigate a combination vaccine strategy involving sequential priming immunizations with different serotypes of adenovirus (Ad)/HIV-1MNenv/rev recombinants and boosting wit...

Downmodulation of Vaccine-Induced Immunity and Protection against the Intracellular Bacterium Francisella tularensis by the Inhibitory Receptor FcγRIIB

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Brian J. Franz

2015-01-01

Full Text Available Fc gamma receptor IIB (FcγRIIB is the only Fc gamma receptor (FcγR which negatively regulates the immune response, when engaged by antigen- (Ag- antibody (Ab complexes. Thus, the generation of Ag-specific IgG in response to infection or immunization has the potential to downmodulate immune protection against infection. Therefore, we sought to determine the impact of FcγRIIB on immune protection against Francisella tularensis (Ft, a Category A biothreat agent. We utilized inactivated Ft (iFt as an immunogen. Naïve and iFt-immunized FcγRIIB knockout (KO or wildtype (WT mice were challenged with Ft-live vaccine strain (LVS. While no significant difference in survival between naïve FcγRIIB KO versus WT mice was observed, iFt-immunized FcγRIIB KO mice were significantly better protected than iFt-immunized WT mice. Ft-specific IgA in serum and bronchial alveolar lavage, as well as IFN-γ, IL-10, and TNF-α production by splenocytes harvested from iFt-immunized FcγRIIB KO, were also significantly elevated. In addition, iFt-immunized FcγRIIB KO mice exhibited a reduction in proinflammatory cytokine levels in vivo at 5 days after challenge, which correlates with increased survival following Ft-LVS challenge in published studies. Thus, these studies demonstrate for the first time the ability of FcγRIIB to regulate vaccine-induced IgA production and downmodulate immunity and protection. The immune mechanisms behind the above observations and their potential impact on vaccine development are discussed.

The New Cellular Immunology

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Claman, Henry N.

1973-01-01

Discusses the nature of the immune response and traces many of the discoveries that have led to the present state of knowledge in immunology. The new cellular immunology is directing its efforts toward improving health by proper manipulation of the immune mechanisms of the body. (JR)

MUC16 provides immune protection by inhibiting synapse formation between NK and ovarian tumor cells

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Migneault Martine

2010-01-01

Full Text Available Abstract Background Cancer cells utilize a variety of mechanisms to evade immune detection and attack. Effective immune detection largely relies on the formation of an immune synapse which requires close contact between immune cells and their targets. Here, we show that MUC16, a heavily glycosylated 3-5 million Da mucin expressed on the surface of ovarian tumor cells, inhibits the formation of immune synapses between NK cells and ovarian tumor targets. Our results indicate that MUC16-mediated inhibition of immune synapse formation is an effective mechanism employed by ovarian tumors to evade immune recognition. Results Expression of low levels of MUC16 strongly correlated with an increased number of conjugates and activating immune synapses between ovarian tumor cells and primary naïve NK cells. MUC16-knockdown ovarian tumor cells were more susceptible to lysis by primary NK cells than MUC16 expressing controls. This increased lysis was not due to differences in the expression levels of the ligands for the activating receptors DNAM-1 and NKG2D. The NK cell leukemia cell line (NKL, which does not express KIRs but are positive for DNAM-1 and NKG2D, also conjugated and lysed MUC16-knockdown cells more efficiently than MUC16 expressing controls. Tumor cells that survived the NKL challenge expressed higher levels of MUC16 indicating selective lysis of MUC16low targets. The higher csMUC16 levels on the NKL resistant tumor cells correlated with more protection from lysis as compared to target cells that were never exposed to the effectors. Conclusion MUC16, a carrier of the tumor marker CA125, has previously been shown to facilitate ovarian tumor metastasis and inhibits NK cell mediated lysis of tumor targets. Our data now demonstrates that MUC16 expressing ovarian cancer cells are protected from recognition by NK cells. The immune protection provided by MUC16 may lead to selective survival of ovarian cancer cells that are more efficient in

Stimulation of host immune defenses by a small molecule protects C. elegans from bacterial infection.

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Pukkila-Worley, Read; Feinbaum, Rhonda; Kirienko, Natalia V; Larkins-Ford, Jonah; Conery, Annie L; Ausubel, Frederick M

2012-01-01

The nematode Caenorhabditis elegans offers currently untapped potential for carrying out high-throughput, live-animal screens of low molecular weight compound libraries to identify molecules that target a variety of cellular processes. We previously used a bacterial infection assay in C. elegans to identify 119 compounds that affect host-microbe interactions among 37,214 tested. Here we show that one of these small molecules, RPW-24, protects C. elegans from bacterial infection by stimulating the host immune response of the nematode. Using transcriptome profiling, epistasis pathway analyses with C. elegans mutants, and an RNAi screen, we show that RPW-24 promotes resistance to Pseudomonas aeruginosa infection by inducing the transcription of a remarkably small number of C. elegans genes (∼1.3% of all genes) in a manner that partially depends on the evolutionarily-conserved p38 MAP kinase pathway and the transcription factor ATF-7. These data show that the immunostimulatory activity of RPW-24 is required for its efficacy and define a novel C. elegans-based strategy to identify compounds with activity against antibiotic-resistant bacterial pathogens.

Stimulation of host immune defenses by a small molecule protects C. elegans from bacterial infection.

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Read Pukkila-Worley

Full Text Available The nematode Caenorhabditis elegans offers currently untapped potential for carrying out high-throughput, live-animal screens of low molecular weight compound libraries to identify molecules that target a variety of cellular processes. We previously used a bacterial infection assay in C. elegans to identify 119 compounds that affect host-microbe interactions among 37,214 tested. Here we show that one of these small molecules, RPW-24, protects C. elegans from bacterial infection by stimulating the host immune response of the nematode. Using transcriptome profiling, epistasis pathway analyses with C. elegans mutants, and an RNAi screen, we show that RPW-24 promotes resistance to Pseudomonas aeruginosa infection by inducing the transcription of a remarkably small number of C. elegans genes (∼1.3% of all genes in a manner that partially depends on the evolutionarily-conserved p38 MAP kinase pathway and the transcription factor ATF-7. These data show that the immunostimulatory activity of RPW-24 is required for its efficacy and define a novel C. elegans-based strategy to identify compounds with activity against antibiotic-resistant bacterial pathogens.

Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model

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Jolene Carlson

2016-10-01

Full Text Available African swine fever (ASF is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV. There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4 virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi. This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN-γ responses, or specific cytokine profiles and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

DNA-encapsulated magnesium phosphate nanoparticles elicit both humoral and cellular immune responses in mice

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Gajadhar Bhakta

2014-01-01

Full Text Available The efficacy of pEGFP (plasmid expressing enhanced green fluorescent protein-encapsulated PEGylated (meaning polyethylene glycol coated magnesium phosphate nanoparticles (referred to as MgPi-pEGFP nanoparticles for the induction of immune responses was investigated in a mouse model. MgPi-pEGFP nanoparticles induced enhanced serum antibody and antigen-specific T-lymphocyte responses, as well as increased IFN-γ and IL-12 levels compared to naked pEGFP when administered via intravenous, intraperitoneal or intramuscular routes. A significant macrophage response, both in size and activity, was also observed when mice were immunized with the nanoparticle formulation. The response was highly specific for the antigen, as the increase in interaction between macrophages and lymphocytes as well as lymphocyte proliferation took place only when they were re-stimulated with recombinant green fluorescence protein (rGFP. Thus the nanoparticle formulation elicited both humoral as well as cellular responses. Cytokine profiling revealed the induction of Th-1 type responses. The results suggest DNA-encapsulated magnesium phosphate (MgPi nanoparticles may constitute a safer, more stable and cost-efficient DNA vaccine formulation.

Intradermal Immunization of Leishmania donovani Centrin Knock-Out Parasites in Combination with Salivary Protein LJM19 from Sand Fly Vector Induces a Durable Protective Immune Response in Hamsters.

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Jacqueline Araújo Fiuza

2016-01-01

Full Text Available Visceral leishmaniasis (VL is a neglected tropical disease and is fatal if untreated. There is no vaccine available against leishmaniasis. The majority of patients with cutaneous leishmaniasis (CL or VL develop a long-term protective immunity after cure from infection, which indicates that development of an effective vaccine against leishmaniasis is possible. Such protection may also be achieved by immunization with live attenuated parasites that do not cause disease. We have previously reported a protective response in mice, hamsters and dogs with Leishmania donovani centrin gene knock-out parasites (LdCen-/-, a live attenuated parasite with a cell division specific centrin1 gene deletion. In this study we have explored the effects of salivary protein LJM19 as an adjuvant and intradermal (ID route of immunization on the efficacy of LdCen-/- parasites as a vaccine against virulent L. donovani.To explore the potential of a combination of LdCen-/- parasites and salivary protein LJM19 as vaccine antigens, LdCen-/- ID immunization followed by ID challenge with virulent L. donovani were performed in hamsters in a 9-month follow up study. We determined parasite burden (serial dilution, antibody production (ELISA and cytokine expression (qPCR in these animals. Compared to controls, animals immunized with LdCen-/- + LJM19 induced a strong antibody response, a reduction in spleen and liver parasite burden and a higher expression of pro-inflammatory cytokines after immunization and one month post-challenge. Additionally, a low parasite load in lymph nodes, spleen and liver, and a non-inflamed spleen was observed in immunized animals 9 months after the challenge infection.Our results demonstrate that an ID vaccination using LdCen-/-parasites in combination with sand fly salivary protein LJM19 has the capability to confer long lasting protection against visceral leishmaniasis that is comparable to intravenous or intracardial immunization.

Gut symbiotic microbes imprint intestinal immune cells with the innate receptor SLAMF4 which contributes to gut immune protection against enteric pathogens.

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Cabinian, Allison; Sinsimer, Daniel; Tang, May; Jang, Youngsoon; Choi, Bongkum; Laouar, Yasmina; Laouar, Amale

2018-05-01

Interactions between host immune cells and gut microbiota are crucial for the integrity and function of the intestine. How these interactions regulate immune cell responses in the intestine remains a major gap in the field. We have identified the signalling lymphocyte activation molecule family member 4 (SLAMF4) as an immunomodulator of the intestinal immunity. The aim is to determine how SLAMF4 is acquired in the gut and what its contribution to intestinal immunity is. Expression of SLAMF4 was assessed in mice and humans. The mechanism of induction was studied using GFP tg bone marrow chimaera mice, lymphotoxin α and TNLG8A-deficient mice, as well as gnotobiotic mice. Role in immune protection was revealed using oral infection with Listeria monocytogenes and Cytobacter rodentium . SLAMF4 is a selective marker of intestinal immune cells of mice and humans. SLAMF4 induction occurs directly in the intestinal mucosa without the involvement of the gut-associated lymphoid tissue. Gut bacterial products, particularly those of gut anaerobes, and gut-resident antigen-presenting cell (APC) TNLG8A are key contributors of SLAMF4 induction in the intestine. Importantly, lack of SLAMF4 expression leads the increased susceptibility of mice to infection by oral pathogens culminating in their premature death. SLAMF4 is a marker of intestinal immune cells which contributes to the protection against enteric pathogens and whose expression is dependent on the presence of the gut microbiota. This discovery provides a possible mechanism for answering the long-standing question of how the intertwining of the host and gut microbial biology regulates immune cell responses in the gut. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Green propolis phenolic compounds act as vaccine adjuvants, improving humoral and cellular responses in mice inoculated with inactivated vaccines

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Geferson Fischer

2010-11-01

Full Text Available Adjuvants play an important role in vaccine formulations by increasing their immunogenicity. In this study, the phenolic compound-rich J fraction (JFR of a Brazilian green propolis methanolic extract stimulated cellular and humoral immune responses when co-administered with an inactivated vaccine against swine herpesvirus type 1 (SuHV-1. When compared to control vaccines that used aluminium hydroxide as an adjuvant, the use of 10 mg/dose of JFR significantly increased (p < 0.05 neutralizing antibody titres against SuHV-1, as well as the percentage of protected animals following SuHV-1 challenge (p < 0.01. Furthermore, addition of phenolic compounds potentiated the performance of the control vaccine, leading to increased cellular and humoral immune responses and enhanced protection of animals after SuHV-1 challenge (p < 0.05. Prenylated compounds such as Artepillin C that are found in large quantities in JFR are likely to be the substances that are responsible for the adjuvant activity.

Rab GTPases in Immunity and Inflammation.

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Prashar, Akriti; Schnettger, Laura; Bernard, Elliott M; Gutierrez, Maximiliano G

2017-01-01

Strict spatiotemporal control of trafficking events between organelles is critical for maintaining homeostasis and directing cellular responses. This regulation is particularly important in immune cells for mounting specialized immune defenses. By controlling the formation, transport and fusion of intracellular organelles, Rab GTPases serve as master regulators of membrane trafficking. In this review, we discuss the cellular and molecular mechanisms by which Rab GTPases regulate immunity and inflammation.

Immune response in bovine neosporosis: Protection or contribution to the pathogenesis of abortion.

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Almería, Sonia; Serrano-Pérez, Beatriz; López-Gatius, Fernando

2017-08-01

Neospora caninum is a protozoan parasite with a preference for cattle and dogs as hosts. When N. caninum infection occurs in cattle it induces abortion, bovine neosporosis being a main cause of abortion worldwide. In dairy cattle, the economic burden of neosporosis-associated abortion is so great that it might results in closure of a farm. However, not all infected cows abort and it is not yet understood why this occurs. At present there is no effective treatment or vaccine. This review provides insights on how immune response against the parasite determines protection or contribution to abortion. Aspects on markers of risk of abortion are also discussed. Humoral immune responses are not protective against N. caninum but seropositivity and antibody level can be good markers for a diagnosis of bovine neosporosis and its associated abortion risk. In addition, humoral mechanisms against N. caninum infection and abortion differ in pure-breed and cross-breed pregnant dairy and beef cattle. Concentrations of Pregnancy Associated glycoprotein -2 (PAG-2) can also be used to predict abortion. A partially protective immune response encompasses increased IFN-γ expression, which has to be counterbalanced by other cytokines such as IL-12 and IL-10, especially towards the end of pregnancy. Although IFN-γ is required to limit parasite proliferation a critical threshold of the IFN-γ response is also required to limit adverse effects on pregnancy. In clinical terms, it may be stated that IFN-γ production and cross-breed pregnancy can protect Neospora-infected dairy cows against abortion. Published by Elsevier Ltd.

Maize Prolamins Could Induce a Gluten-Like Cellular Immune Response in Some Celiac Disease Patients

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Ortiz-Sánchez, Juan P.; Cabrera-Chávez, Francisco; Calderón de la Barca, Ana M.

2013-01-01

Celiac disease (CD) is an autoimmune-mediated enteropathy triggered by dietary gluten in genetically prone individuals. The current treatment for CD is a strict lifelong gluten-free diet. However, in some CD patients following a strict gluten-free diet, the symptoms do not remit. These cases may be refractory CD or due to gluten contamination; however, the lack of response could be related to other dietary ingredients, such as maize, which is one of the most common alternatives to wheat used in the gluten-free diet. In some CD patients, as a rare event, peptides from maize prolamins could induce a celiac-like immune response by similar or alternative pathogenic mechanisms to those used by wheat gluten peptides. This is supported by several shared features between wheat and maize prolamins and by some experimental results. Given that gluten peptides induce an immune response of the intestinal mucosa both in vivo and in vitro, peptides from maize prolamins could also be tested to determine whether they also induce a cellular immune response. Hypothetically, maize prolamins could be harmful for a very limited subgroup of CD patients, especially those that are non-responsive, and if it is confirmed, they should follow, in addition to a gluten-free, a maize-free diet. PMID:24152750

Immune activation alters cellular and humoral responses to yellow fever 17D vaccine.

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Muyanja, Enoch; Ssemaganda, Aloysius; Ngauv, Pearline; Cubas, Rafael; Perrin, Helene; Srinivasan, Divya; Canderan, Glenda; Lawson, Benton; Kopycinski, Jakub; Graham, Amanda S; Rowe, Dawne K; Smith, Michaela J; Isern, Sharon; Michael, Scott; Silvestri, Guido; Vanderford, Thomas H; Castro, Erika; Pantaleo, Giuseppe; Singer, Joel; Gillmour, Jill; Kiwanuka, Noah; Nanvubya, Annet; Schmidt, Claudia; Birungi, Josephine; Cox, Josephine; Haddad, Elias K; Kaleebu, Pontiano; Fast, Patricia; Sekaly, Rafick-Pierre; Trautmann, Lydie; Gaucher, Denis

2014-07-01

Defining the parameters that modulate vaccine responses in African populations will be imperative to design effective vaccines for protection against HIV, malaria, tuberculosis, and dengue virus infections. This study aimed to evaluate the contribution of the patient-specific immune microenvironment to the response to the licensed yellow fever vaccine 17D (YF-17D) in an African cohort. We compared responses to YF-17D in 50 volunteers in Entebbe, Uganda, and 50 volunteers in Lausanne, Switzerland. We measured the CD8+ T cell and B cell responses induced by YF-17D and correlated them with immune parameters analyzed by flow cytometry prior to vaccination. We showed that YF-17D-induced CD8+ T cell and B cell responses were substantially lower in immunized individuals from Entebbe compared with immunized individuals from Lausanne. The impaired vaccine response in the Entebbe cohort associated with reduced YF-17D replication. Prior to vaccination, we observed higher frequencies of exhausted and activated NK cells, differentiated T and B cell subsets and proinflammatory monocytes, suggesting an activated immune microenvironment in the Entebbe volunteers. Interestingly, activation of CD8+ T cells and B cells as well as proinflammatory monocytes at baseline negatively correlated with YF-17D-neutralizing antibody titers after vaccination. Additionally, memory T and B cell responses in preimmunized volunteers exhibited reduced persistence in the Entebbe cohort but were boosted by a second vaccination. Together, these results demonstrate that an activated immune microenvironment prior to vaccination impedes efficacy of the YF-17D vaccine in an African cohort and suggest that vaccine regimens may need to be boosted in African populations to achieve efficient immunity. Registration is not required for observational studies. This study was funded by Canada's Global Health Research Initiative, Defense Threat Reduction Agency, National Institute of Allergy and Infectious Diseases

Canine Distemper Virus (CDV) immune-stimulating complexes (iscoms), but not measles virus iscoms, protect dogs against CDV infection.

NARCIS (Netherlands)

P. de Vries (Petra); F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

1988-01-01

textabstractThe potential of immune-stimulating complexes (iscoms), a novel form of antigenic presentation, for the induction of protective immunity against morbillivirus infection was shown by immunizing dogs with canine distemper virus (CDV) iscoms, which contained the fusion (F) protein and a

La protéine CG4572 de Drosophile et la propagation du signal ARNi immun antiviral

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Karlikow , Margot

2015-01-01

During viral infection, cell survival will depend on adequately giving, receiving and processing information to establish an efficient antiviral immune response. Cellular communication is therefore essential to allow the propagation of immune signals that will confer protection to the entire organism.The major antiviral defense in insects is the RNA interference (RNAi) mechanism that is activated by detection of viral double-stranded RNA (dsRNA). The antiviral RNAi mechanism can be divided in...

Growth, immune responses and protection of Nile tilapia Oreochromis niloticus immunized with formalin-killed Streptococcus agalactiae serotype Ia and III vaccines

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Atchariya Suwannasang

2017-08-01

Full Text Available The protective efficacy of formalin-killed Streptococcus agalactiae (Group B Streptococcus, GBS serotype Ia (GBS-Ia and III (GBS-III vaccines were assessed in Nile tilapia (Oreochromis niloticus. The fish with an average weight of 34.45± 0.08 g were immunized by intraperitoneal (i.p. injection with 4 different formalin-killed vaccines prepared from GBS-Ia (1x1010 CFU/mL, GBS-III (1x1010 CFU/mL, and combined GBS-Ia and GBS-III in an equal volume at final concentrations 1x1010 CFU/mL and 2x1010 CFU/mL in comparison with the non-immunized control group. At 2 and 4 weeks post vaccination, no significant differences were observed (p>0.05 among treatments in growth performance or haemato-immunological parameters, except the increased red blood cell at 2 weeks. Significantly increased antibody titers (p<0.05 against GBS-Ia and GBS-III antigens were noted in the groups immunized with homologous GBS vaccines, whereas the group reacted with heterologous GBS antigen showed less antibody titer as compared with the control group. The vaccination experiment indicated that i.p. injection of Nile tilapia with formalin-killed cells prepared from GBS-Ia or GBS-III provides significant protection, with relative percent survival (RPS value of 52.17 to 71.42%, against a challenge with the homologous serotype isolate, whereas the RPS in fish challenged with a heterologous serotype isolate varied from 20.00 to 53.57%. These results suggested that vaccines from either GBS-Ia or GBS-III have insufficient cross-protective efficacy against the other serotypes. However, a mixed vaccine produced from both GBS serotypes Ia and III provided significant protection with 65.00 to 95.66% RPS which could be an excellent vaccine to protect fish against streptococcosis caused by both GBS serotypes Ia and III.

Phi ({Phi}) and psi ({Psi}) angles involved in malarial peptide bonds determine sterile protective immunity

Energy Technology Data Exchange (ETDEWEB)

Patarroyo, Manuel E., E-mail: mepatarr@gmail.com [Fundacion Instituto de Inmunologia de Colombia (FIDIC), Bogota (Colombia); Universidad Nacional de Colombia, Bogota (Colombia); Moreno-Vranich, Armando; Bermudez, Adriana [Fundacion Instituto de Inmunologia de Colombia (FIDIC), Bogota (Colombia)

2012-12-07

Highlights: Black-Right-Pointing-Pointer Phi ({Phi}) and psi ({Psi}) angles determine sterile protective immunity. Black-Right-Pointing-Pointer Modified peptide's tendency to assume a regular conformation related to a PPII{sub L}. Black-Right-Pointing-Pointer Structural modifications in mHABPs induce Ab and protective immunity. Black-Right-Pointing-Pointer mHABP backbone atom's interaction with HLA-DR{beta}1{sup Asterisk-Operator} is stabilised by H-bonds. -- Abstract: Modified HABP (mHABP) regions interacting with HLA-DR{beta}1{sup Asterisk-Operator} molecules have a more restricted conformation and/or sequence than other mHABPs which do not fit perfectly into their peptide binding regions (PBR) and do not induce an acceptable immune response due to the critical role of their {Phi} and {Psi} torsion angles. These angle's critical role was determined in such highly immunogenic, protection-inducing response against experimental malaria using the conformers (mHABPs) obtained by {sup 1}H-NMR and superimposed into HLA-DR{beta}1{sup Asterisk-Operator }-like Aotus monkey molecules; their phi ({Phi}) and psi ({Psi}) angles were measured and the H-bond formation between these molecules was evaluated. The aforementioned mHABP propensity to assume a regular conformation similar to a left-handed polyproline type II helix (PPII{sub L}) led to suggesting that favouring these conformations according to their amino acid sequence would lead to high antibody titre production and sterile protective immunity induction against malaria, thereby adding new principles or rules for vaccine development, malaria being one of them.

Augmentation of cellular and humoral immune responses to HPV16 and HPV18 E6 and E7 antigens by VGX-3100

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Matthew P Morrow

2016-01-01

Full Text Available We have previously demonstrated the immunogenicity of VGX-3100, a multicomponent DNA immunotherapy for the treatment of Human Papillomavirus (HPV16/18-positive CIN2/3 in a phase 1 clinical trial. Here, we report on the ability to boost immune responses with an additional dose of VGX-3100. Patients completing our initial phase 1 trial were offered enrollment into a follow on trial consisting of a single boost dose of VGX-3100. Data show both cellular and humoral immune responses could be augmented above pre-boost levels, including the induction of interferon (IFNγ production, tumor necrosis factor (TNFα production, CD8+ T cell activation and the synthesis of lytic proteins. Moreover, observation of antigen-specific regulation of immune-related gene transcripts suggests the induction of a proinflammatory response following the boost. Analysis of T cell receptor (TCR sequencing suggests the localization of putative HPV-specific T cell clones to the cervical mucosa, which underscores the putative mechanism of action of lesion regression and HPV16/18 elimination noted in our double-blind placebo-controlled phase 2B trial. Taken together, these data indicate that VGX-3100 drives the induction of robust cellular and humoral immune responses that can be augmented by a fourth “booster” dose. These data could be important in the scope of increasing the clinical efficacy rate of VGX-3100.

Recent progress in host immunity to avian coccidiosis: IL-17 family cytokines as sentinels of the intestinal mucosa.

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Min, Wongi; Kim, Woo H; Lillehoj, Erik P; Lillehoj, Hyun S

2013-11-01

The molecular and cellular mechanisms leading to immune protection against coccidiosis are complex and include multiple aspects of innate and adaptive immunities. Innate immunity is mediated by various subpopulations of immune cells that recognize pathogen associated molecular patterns (PAMPs) through their pattern recognition receptors (PRRs) leading to the secretion of soluble factors with diverse functions. Adaptive immunity, which is important in conferring protection against subsequent reinfections, involves subtypes of T and B lymphocytes that mediate antigen-specific immune responses. Recently, global gene expression microarray analysis has been used in an attempt to dissect this complex network of immune cells and molecules during avian coccidiosis. These new studies emphasized the uniqueness of the innate immune response to Eimeria infection, and directly led to the discovery of previously uncharacterized host genes and proteins whose expression levels were modulated following parasite infection. Among these is the IL-17 family of cytokines. This review highlights recent progress in IL-17 research in the context of host immunity to avian coccidiosis. Copyright © 2013. Published by Elsevier Ltd.

Cellular and Molecular Mechanisms of Anterior Chamber-Associated Immune Deviation (ACAID: What We Have Learned from Knockout Mice

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Julie Vendomèle

2017-11-01

Full Text Available Anterior chamber-associated immune deviation (ACAID is a well-known phenomenon that can occur after an antigen is introduced without any danger signal into the anterior chamber of a murine eye. It is reported to lead to an antigen-specific immune deviation throughout the body. Despite the relatively little evidence of this phenomenon in humans, it has been suggested as a potential prophylactic strategy in allograft rejections and in several autoimmune diseases. Cellular and molecular mechanisms of ACAID have been explored in different murine models mainly as proofs of concept, first by direct analyses of immune components in normal immunocompetent settings and by cell transfer experiments. Later, use of knockout (KO mice has helped considerably to decipher ACAID mechanisms. However, several factors raise questions about the reliability and validity of studies using KO murine models. This mini-review summarizes results obtained with KO mice and discusses their advantages, their potential weaknesses, and their potential methods for further progress.

Vaccination with an Attenuated Mutant of Ehrlichia chaffeensis Induces Pathogen-Specific CD4+ T Cell Immunity and Protection from Tick-Transmitted Wild-Type Challenge in the Canine Host.

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Jodi L McGill

Full Text Available Ehrlichia chaffeensis is a tick-borne rickettsial pathogen and the causative agent of human monocytic ehrlichiosis. Transmitted by the Amblyomma americanum tick, E. chaffeensis also causes disease in several other vertebrate species including white-tailed deer and dogs. We have recently described the generation of an attenuated mutant strain of E. chaffeensis, with a mutation in the Ech_0660 gene, which is able to confer protection from secondary, intravenous-administered, wild-type E. chaffeensis infection in dogs. Here, we extend our previous results, demonstrating that vaccination with the Ech_0660 mutant protects dogs from physiologic, tick-transmitted, secondary challenge with wild-type E. chaffeensis; and describing, for the first time, the cellular and humoral immune responses induced by Ech_0660 mutant vaccination and wild-type E. chaffeensis infection in the canine host. Both vaccination and infection induced a rise in E. chaffeensis-specific antibody titers and a significant Th1 response in peripheral blood as measured by E. chaffeensis antigen-dependent CD4+ T cell proliferation and IFNγ production. Further, we describe for the first time significant IL-17 production by peripheral blood leukocytes from both Ech_0660 mutant vaccinated animals and control animals infected with wild-type E. chaffeensis, suggesting a previously unrecognized role for IL-17 and Th17 cells in the immune response to rickettsial pathogens. Our results are a critical first step towards defining the role of the immune system in vaccine-induced protection from E. chaffeensis infection in an incidental host; and confirm the potential of the attenuated mutant clone, Ech_0660, to be used as a vaccine candidate for protection against tick-transmitted E. chaffeensis infection.

Improving the Th1 cellular efficacy of the lead Yersinia pestis rF1-V subunit vaccine using SA-4-1BBL as a novel adjuvant.

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Dinc, Gunes; Pennington, Jarrod M; Yolcu, Esma S; Lawrenz, Matthew B; Shirwan, Haval

2014-09-03

The lead candidate plague subunit vaccine is the recombinant fusion protein rF1-V adjuvanted with alum. While alum generates Th2 regulated robust humoral responses, immune protection against Yersinia pestis has been shown to also involve Th1 driven cellular responses. Therefore, the rF1-V-based subunit vaccine may benefit from an adjuvant system that generates a mixed Th1 and humoral immune response. We herein assessed the efficacy of a novel SA-4-1BBL costimulatory molecule as a Th1 adjuvant to improve cellular responses generated by the rF1-V vaccine. SA-4-1BBL as a single adjuvant had better efficacy than alum in generating CD4(+) and CD8(+) T cells producing TNFα and IFNγ, signature cytokines for Th1 responses. The combination of SA-4-1BBL with alum further increased this Th1 response as compared with the individual adjuvants. Analysis of the humoral response revealed that SA-4-1BBL as a single adjuvant did not generate a significant Ab response against rF1-V, and SA-4-1BBL in combination with alum did not improve Ab titers. However, the combined adjuvants significantly increased the ratio of Th1 regulated IgG2c in C57BL/6 mice to the Th2 regulated IgG1. Finally, a single vaccination with rF1-V adjuvanted with SA-4-1BBL+alum had better protective efficacy than vaccines containing individual adjuvants. Taken together, these results demonstrate that SA-4-1BBL improves the protective efficacy of the alum adjuvanted lead rF1-V subunit vaccine by generating a more balanced Th1 cellular and humoral immune response. As such, this adjuvant platform may prove efficacious not only for the rF1-V vaccine but also against other infections that require both cellular and humoral immune responses for protection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Schistosoma mansoni: analysis of the humoral and cellular basis of resistance in guinea-pigs vaccinated with radiation-attenuated cercariae

International Nuclear Information System (INIS)

McLaren, D.J.; Delgado, V.S.; Gordon, J.R.; Rogers, M.V.

1990-01-01

This study addresses the humoral and cellular basis of specific acquired immunity in the guinea-pig irradiated vaccine model of schistosomiasis mansoni. Rodents vaccinated with 500 gamma-irradiated cercariae and then splenectomized 4. 5 weeks later showed a 33% reduction in resistance to challenge as compared to vaccinated animals or vaccinated/sham splenectomized controls. Serum harvested from once vaccinated individuals conferred modest levels of resistance upon naive recipients in some experiments, but transfer was not achieved consistently. Serum from vaccinated and thrice boosted rodents (Vbbb) routinely transferred about 45% immunity, however, provided it was given in 4 ml aliquots on day 9 post-challenge; Vbbb serum thus transferred 50% of donor immunity. Interestingly, multiple doses of this protective serum given on and either side of day 9 did not enhance the protection achieved with a single 4 ml aliquot. Neither peripheral lymph node cells nor splenocytes from the polyvaccinated serum donors were able to transfer resistance to recipient guinea-pigs and they failed to augment the protection achieved with Vbbb serum. Foot-pad testing revealed no correlation between delayed hypersensitivity responses and immunity to challenge in vaccinated guinea-pigs. Polyvaccine guinea-pig serum failed to protect mice and guinea-pigs could not be protected with polyvaccine rat serum. (author)

Reversibility of alcohol-induced immune depression

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Tønnesen, H; Kaiser, A H; Nielsen, B B

1992-01-01

Alcohol abusers have suppressed cellular immune function. The aim of the study was to investigate the time of sobriety required to normalize immune function. Delayed hypersensitivity was investigated during disulfiram controlled abstinence in ten heavy alcoholics and in seven moderate drinkers...... months of abstinence. The results suggest that while 2 weeks of abstinence from alcohol will improve the depressed cellular immunity, 2 months of sobriety is necessary to normalize it....

Rab GTPases in Immunity and Inflammation

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Akriti Prashar

2017-09-01

Full Text Available Strict spatiotemporal control of trafficking events between organelles is critical for maintaining homeostasis and directing cellular responses. This regulation is particularly important in immune cells for mounting specialized immune defenses. By controlling the formation, transport and fusion of intracellular organelles, Rab GTPases serve as master regulators of membrane trafficking. In this review, we discuss the cellular and molecular mechanisms by which Rab GTPases regulate immunity and inflammation.

Cellular and molecular immune responses of the sea bass (Dicentrarchus labrax) experimentally infected with betanodavirus

DEFF Research Database (Denmark)

Scapigliati, G.; Buonocore, F.; Randelli, E.

2010-01-01

and acquired responses: type I IFN, Mx, IL-1, Cox-2; IL-10, TGF-β, TCRβ, CD4, CD8α, IgM, by using a quantitative PCR array system developed for sea bass. The obtained results showed a detectable increase of T cells and B cells in PBL during betanodavirus infection. Furthermore, leucocytes obtained from blood...... was also observed, while the other tested genes did not show any significant variations with respect to mock-treated fish. Overall, our work represents a first comprehensive analysis of cellular and molecular immune parameters in a fish species exposed to a pathogenic virus....

Innate Immunity and Breast Milk

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Nicole Theresa Cacho

2017-05-01

Full Text Available Human milk is a dynamic source of nutrients and bioactive factors; unique in providing for the human infant’s optimal growth and development. The growing infant’s immune system has a number of developmental immune deficiencies placing the infant at increased risk of infection. This review focuses on how human milk directly contributes to the infant’s innate immunity. Remarkable new findings clarify the multifunctional nature of human milk bioactive components. New research techniques have expanded our understanding of the potential for human milk’s effect on the infant that will never be possible with milk formulas. Human milk microbiome directly shapes the infant’s intestinal microbiome, while the human milk oligosaccharides drive the growth of these microbes within the gut. New techniques such as genomics, metabolomics, proteomics, and glycomics are being used to describe this symbiotic relationship. An expanded role for antimicrobial proteins/peptides within human milk in innate immune protection is described. The unique milieu of enhanced immune protection with diminished inflammation results from a complex interaction of anti-inflammatory and antioxidative factors provided by human milk to the intestine. New data support the concept of mucosal-associated lymphoid tissue and its contribution to the cellular content of human milk. Human milk stem cells (hMSCs have recently been discovered. Their direct role in the infant for repair and regeneration is being investigated. The existence of these hMSCs could prove to be an easily harvested source of multilineage stem cells for the study of cancer and tissue regeneration. As the infant’s gastrointestinal tract and immune system develop, there is a comparable transition in human milk over time to provide fewer immune factors and more calories and nutrients for growth. Each of these new findings opens the door to future studies of human milk and its effect on the innate immune system

Immunity induced shortly after DNA vaccination of rainbow trout against rhabdoviruses protects against heterologous virus but not against bacterial pathogens

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Lorenzen, Niels; Lorenzen, Ellen; Einer-Jensen, Katja

2002-01-01

whereas no increased survival was found upon challenge with bacterial pathogens. Within two months after vaccination, the cross-protection disappeared while the specific immunity to homologous virus remained high. The early immunity induced by the DNA vaccines thus appeared to involve short-lived non......It was recently reported that DNA vaccination of rainbow trout fingerlings against viral hemorrhagic septicaemia virus (VHSV) induced protection within 8 days after intramuscular injection of plasmid DNA. In order to analyse the specificity of this early immunity, fish were vaccinated with plasmid...... DNA encoding the VHSV or the infectious haematopoietic necrosis virus (IHNV) glycoprotein genes and later challenged with homologous or heterologous pathogens. Challenge experiments revealed that immunity established shortly after vaccination was cross-protective between the two viral pathogens...

The Unfolded Protein Response in Homeostasis and Modulation of Mammalian Immune Cells.

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Martins, Ana Sofia; Alves, Inês; Helguero, Luisa; Domingues, Maria Rosário; Neves, Bruno Miguel

2016-11-01

The endoplasmic reticulum (ER) plays important roles in eukaryotic protein folding and lipid biosynthesis. Several exogenous and endogenous cellular sources of stress can perturb ER homeostasis leading to the accumulation of unfolded proteins in the lumen. Unfolded protein accumulation triggers a signal-transduction cascade known as the unfolded protein response (UPR), an adaptive mechanism which aims to protect cells from protein aggregates and to restore ER functions. Further to this protective mechanism, in immune cells, UPR molecular effectors have been shown to participate in a wide range of biological processes such as cell differentiation, survival and immunoglobulin and cytokine production. Recent findings also highlight the involvement of the UPR machinery in the maturational program and antigen presentation capacities of dendritic cells. UPR is therefore a key element in immune system homeostasis with direct implications on both adaptive and innate immune responses. The present review summarizes the knowledge on the emerging roles of UPR signaling cascades in mammalian immune cells as well as the consequences of their dysregulation in relation to the pathogenesis of several diseases.

Mechanisms of stage-transcending protection following immunization of mice with late liver stage-arresting genetically attenuated malaria parasites.

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Brandon K Sack

2015-05-01

Full Text Available Malaria, caused by Plasmodium parasite infection, continues to be one of the leading causes of worldwide morbidity and mortality. Development of an effective vaccine has been encumbered by the complex life cycle of the parasite that has distinct pre-erythrocytic and erythrocytic stages of infection in the mammalian host. Historically, malaria vaccine development efforts have targeted each stage in isolation. An ideal vaccine, however, would target multiple life cycle stages with multiple arms of the immune system and be capable of eliminating initial infection in the liver, the subsequent blood stage infection, and would prevent further parasite transmission. We have previously shown that immunization of mice with Plasmodium yoelii genetically attenuated parasites (GAP that arrest late in liver stage development elicits stage-transcending protection against both a sporozoite challenge and a direct blood stage challenge. Here, we show that this immunization strategy engenders both T- and B-cell responses that are essential for stage-transcending protection, but the relative importance of each is determined by the host genetic background. Furthermore, potent anti-blood stage antibodies elicited after GAP immunization rely heavily on FC-mediated functions including complement fixation and FC receptor binding. These protective antibodies recognize the merozoite surface but do not appear to recognize the immunodominant merozoite surface protein-1. The antigen(s targeted by stage-transcending immunity are present in both the late liver stages and blood stage parasites. The data clearly show that GAP-engendered protective immune responses can target shared antigens of pre-erythrocytic and erythrocytic parasite life cycle stages. As such, this model constitutes a powerful tool to identify novel, protective and stage-transcending T and B cell targets for incorporation into a multi-stage subunit vaccine.

Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

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Dagoberto Sepúlveda

Full Text Available DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV, an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach, and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach. For the in vitro approach, the virus collected from the last passage (passaged virus was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms.

Mathematical Modeling of Tuberculosis Bacillary Counts and Cellular Populations in the Organs of Infected Mice

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Bru, Antonio; Cardona, Pere-Joan

2010-01-01

Background Mycobacterium tuberculosis is a particularly aggressive microorganism and the host's defense is based on the induction of cellular immunity, in which the creation of a granulomatous structure has an important role. Methodology We present here a new 2D cellular automata model based on the concept of a multifunctional process that includes key factors such as the chemokine attraction of the cells; the role of innate immunity triggered by natural killers; the presence of neutrophils; apoptosis and necrosis of infected macrophages; the removal of dead cells by macrophages, which induces the production of foamy macrophages (FMs); the life cycle of the bacilli as a determinant for the evolution of infected macrophages; and the immune response. Results The results obtained after the inclusion of two degrees of tolerance to the inflammatory response triggered by the infection shows that the model can cover a wide spectrum, ranging from highly-tolerant (i.e. mice) to poorly-tolerant hosts (i.e. mini-pigs or humans). Conclusions This model suggest that stopping bacillary growth at the onset of the infection might be difficult and the important role played by FMs in bacillary drainage in poorly-tolerant hosts together with apoptosis and innate lymphocytes. It also shows the poor ability of the cellular immunity to control the infection, provides a clear protective character to the granuloma, due its ability to attract a sufficient number of cells, and explains why an already infected host can be constantly reinfected. PMID:20886087

Protective immune responses with trickle infections of third-stage filarial larvae of Wuchereria bancrofti in mice.

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Rajasekariah, G R; Monteiro, Y M; Netto, A; Deshpande, L; Subrahmanyam, D

1989-01-01

Groups of inbred BALB/c mice were immunized with trickle doses of 20 live third-stage larvae (L3) of Wuchereria bancrofti each subcutaneously or with 150 microg of sonicated microfilarial antigens emulsified in Freund's adjuvant intramuscularly. An antibody response was distinctly seen after seven trickle doses of L3 and following with the sonicated microfilarial immunization. Due to the non-permissive nature of inbred mice to W. bancrofti infections, a novel immunization approach was adopted using appropriate age- and sex-matched controls. The anti-L3 response in terms of antibody-dependent cell-mediated adhesion and killing was assessed in the immunized animals by implanting live L3 in micropore chambers subcutaneously. About 75% L3 W. bancrofti were affected in animals sensitized with seven trickle doses of L3. When sensitizations were continued, as high as 92% of L3 were seen affected with ten trickle doses compared with 27% in age-matched controls. Immunization with sonicated microfilarial antigen affected about 70% of L3 as opposed to only 12% in controls. A positive correlation was observed in the antibody response with protectivity. This method of induction and assessment of the anti-L3 response involving a small set of animals has not only allowed quantification of affected L3 but has also enabled us to visualize larval conditions in immunologically activated animals. The micropore chamber system, would be useful in monitoring the induction of protective immune response against W. bancrofti in inbred mice. Experimentation on large numbers of animals is required to elucidate further the response of mice towards L3 and also to pinpoint the putative protective antigens. PMID:12412764

Vaccination with dengue virus-like particles induces humoral and cellular immune responses in mice

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Zhang Quanfu

2011-06-01

Full Text Available Abstract Background The incidence of dengue, an infectious disease caused by dengue virus (DENV, has dramatically increased around the world in recent decades and is becoming a severe public health threat. However, there is currently no specific treatment for dengue fever, and licensed vaccine against dengue is not available. Vaccination with virus-like particles (VLPs has shown considerable promise for many viral diseases, but the effect of DENV VLPs to induce specific immune responses has not been adequately investigated. Results By optimizing the expression plasmids, recombinant VLPs of four antigenically different DENV serotypes DENV1-4 were successfully produced in 293T cells. The vaccination effect of dengue VLPs in mice showed that monovalent VLPs of each serotype stimulated specific IgG responses and potent neutralizing antibodies against homotypic virus. Tetravalent VLPs efficiently enhanced specific IgG and neutralizing antibodies against all four serotypes of DENV. Moreover, vaccination with monovalent or tetravalent VLPs resulted in the induction of specific cytotoxic T cell responses. Conclusions Mammalian cell expressed dengue VLPs are capable to induce VLP-specific humoral and cellular immune responses in mice, and being a promising subunit vaccine candidate for prevention of dengue virus infection.

Mechanisms of protective immunity against Schistosoma mansoni infection in mice vaccinated with irradiated cercaria- I. analysis of antibody and T-lymphocyte responses in mouse strains developing differing levels of immunity

International Nuclear Information System (INIS)

James, S.L.; Labine, M.; Sher, A.

1981-01-01

The kinetics of cellular and humoral responses directed against schistosomula were examined in mice of three inbred strains which demonstrate differences in the degree of resistance induced by immunization with irradiated cercariae. T-Cell reactivity was observed during the first 4 weeks after vaccination but declined to control levels thereafter. Anti-schistosomulum antibody was first detected 2 weeks after vaccination, peaked by 6 weeks, and persisted as late as 15 weeks. In sera obtained at 6 weeks, antibody activity was detected in affinity chromatography-purified fractions containing IgM, IgA, IgG 1 , IgG 2 /sub a/, and IgG 3 immunoglobulins. In general, the cellular and humoral responses observed in C57Bl/6J mice, which consistently developed a high level of immunity after vaccination, were not significantly different from those observed in C3H/HeJ or CBA/J mice, which achieved only low to moderate levels of immunity. Thus, although antibody production appears to correlate more closely than T lymphocyte responsiveness with the typical long-term resistance pattern observed in this model, the absence of striking differences in parasite-specific antibody levels between mice of these different strains suggests that additional mechanisms may be involved in the development of immunity after vaccination

Immune Privilege and Eye-Derived T-Regulatory Cells

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Hiroshi Keino

2018-01-01

Full Text Available Certain cellular components of the eye, such as neural retina, are unable to regenerate and replicate after destructive inflammation. Ocular immune privilege provides the eye with immune protection against intraocular inflammation in order to minimize the risk to vision integrity. The eye and immune system use strategies to maintain the ocular immune privilege by regulating the innate and adaptive immune response, which includes immunological ignorance, peripheral tolerance to eye-derived antigens, and intraocular immunosuppressive microenvironment. In this review, we summarize current knowledge regarding the molecular mechanism responsible for the development and maintenance of ocular immune privilege via regulatory T cells (Tregs, which are generated by the anterior chamber-associated immune deviation (ACAID, and ocular resident cells including corneal endothelial (CE cells, ocular pigment epithelial (PE cells, and aqueous humor. Furthermore, we examined the therapeutic potential of Tregs generated by RPE cells that express transforming growth factor beta (TGF-β, cytotoxic T lymphocyte-associated antigen-2 alpha (CTLA-2α, and retinoic acid for autoimmune uveoretinitis and evaluated a new strategy using human RPE-induced Tregs for clinical application in inflammatory ocular disease. We believe that a better understanding of the ocular immune privilege associated with Tregs might offer a new approach with regard to therapeutic interventions for ocular autoimmunity.

Immune Privilege and Eye-Derived T-Regulatory Cells.

Science.gov (United States)

Keino, Hiroshi; Horie, Shintaro; Sugita, Sunao

2018-01-01

Certain cellular components of the eye, such as neural retina, are unable to regenerate and replicate after destructive inflammation. Ocular immune privilege provides the eye with immune protection against intraocular inflammation in order to minimize the risk to vision integrity. The eye and immune system use strategies to maintain the ocular immune privilege by regulating the innate and adaptive immune response, which includes immunological ignorance, peripheral tolerance to eye-derived antigens, and intraocular immunosuppressive microenvironment. In this review, we summarize current knowledge regarding the molecular mechanism responsible for the development and maintenance of ocular immune privilege via regulatory T cells (Tregs), which are generated by the anterior chamber-associated immune deviation (ACAID), and ocular resident cells including corneal endothelial (CE) cells, ocular pigment epithelial (PE) cells, and aqueous humor. Furthermore, we examined the therapeutic potential of Tregs generated by RPE cells that express transforming growth factor beta (TGF- β ), cytotoxic T lymphocyte-associated antigen-2 alpha (CTLA-2 α ), and retinoic acid for autoimmune uveoretinitis and evaluated a new strategy using human RPE-induced Tregs for clinical application in inflammatory ocular disease. We believe that a better understanding of the ocular immune privilege associated with Tregs might offer a new approach with regard to therapeutic interventions for ocular autoimmunity.

Imidacloprid intensifies its impact on honeybee and bumblebee cellular immune response when challenged with LPS (lippopolysacharide) of Escherichia coli.

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Walderdorff, Louise; Laval-Gilly, Philippe; Bonnefoy, Antoine; Falla-Angel, Jaïro

2018-05-16

Insect hemocytes play an important role in insects' defense against environmental stressors as they are entirely dependent on their innate immune system for pathogen defense. In recent years a dramatic decline of pollinators has been reported in many countries. The drivers of this declines appear to be associated with pathogen infections like viruses, bacteria or fungi in combination with pesticide exposure. The aim of this study was thus to investigate the impact of imidacloprid, a neonicotinoid insecticide, on the cellular immune response of two pollinators (Apis mellifera and Bombus terrestris) during simultaneous immune activation with LPS (lipopolysaccharide) of Escherichia coli. For this purpose the phagocytosis capacity as well as the production of H 2 O 2 and NO of larval hemocytes, exposed to five different imidacloprid concentrations in vitro, was measured. All used pesticide concentrations showed a weakening effect on phagocytosis with but also without LPS activation. Imidacloprid decreased H 2 O 2 and increased NO production in honeybees. Immune activation by LPS clearly reinforced the effect of imidacloprid on the immune response of hemocytes in all three immune parameters tested. Bumblebee hemocytes appeared more sensitive to imidacloprid during phagocytosis assays while imidacloprid showed a greater impact on honeybee hemocytes during H 2 O 2 and NO production. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of anti-schistosomal chemotherapy on immune responses, protection and immunity. II. Concomitant immunity and immunization with irradiated cercariae

International Nuclear Information System (INIS)

Tawfik, A.F.; Colley, D.G.

1986-01-01

Resistance of mice to challenge infections of Schistosoma mansoni was evaluated before and after elimination of their primary, established S. mansoni infections with the chemotherapeutic drug praziquantel. Mice treated after either 10 or 20 weeks of primary infection were challenged 6 or 10 weeks after treatment. Mice infected for for 10 weeks prior to treatment expressed progressively less resistance 6 and 10 weeks after treatment. By 10 weeks after treatment significant levels of protection were no longer observed. Resistance waned more slowly if mice were treated 20 weeks after infection, and there was still significant expression of resistance to challenge 10 weeks after treatment. A separate set of experiments evaluated the use of highly irradiated cercariae as a vaccine in mice that had been previously infected with S. mansoni and cured with praziquantel. It was observed that effective immunizations were possible in previously infected mice. These studies demonstrate that established resistance waned after treatment and the rate of loss of protection was dependent upon the duration of infection prior to treatment. Furthermore, the irradiated cercarial vaccine studies indicate that in the murine model induction of immunological resistance was feasible following chemotherapeutic treatment of infected populations

Booster vaccination with safe, modified, live-attenuated mutants of Brucella abortus strain RB51 vaccine confers protective immunity against virulent strains of B. abortus and Brucella canis in BALB/c mice.

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Truong, Quang Lam; Cho, Youngjae; Kim, Kiju; Park, Bo-Kyoung; Hahn, Tae-Wook

2015-11-01

Brucella abortus attenuated strain RB51 vaccine (RB51) is widely used in prevention of bovine brucellosis. Although vaccination with this strain has been shown to be effective in conferring protection against bovine brucellosis, RB51 has several drawbacks, including residual virulence for animals and humans. Therefore, a safe and efficacious vaccine is needed to overcome these disadvantages. In this study, we constructed several gene deletion mutants (ΔcydC, ΔcydD and ΔpurD single mutants, and ΔcydCΔcydD and ΔcydCΔpurD double mutants) of RB51 with the aim of increasing the safety of the possible use of these mutants as vaccine candidates. The RB51ΔcydC, RB51ΔcydD, RB51ΔpurD, RB51ΔcydCΔcydD and RB51ΔcydCΔpurD mutants exhibited significant attenuation of virulence when assayed in murine macrophages in vitro or in BALB/c mice. A single intraperitoneal immunization with RB51ΔcydC, RB51ΔcydD, RB51ΔcydCΔcydD or RB51ΔcydCΔpurD mutants was rapidly cleared from mice within 3 weeks, whereas the RB51ΔpurD mutant and RB51 were detectable in spleens until 4 and 7 weeks, respectively. Vaccination with a single dose of RB51 mutants induced lower protective immunity in mice than did parental RB51. However, a booster dose of these mutants provided significant levels of protection in mice against challenge with either the virulent homologous B. abortus strain 2308 or the heterologous Brucella canis strain 26. In addition, these mutants were found to induce a mixed but T-helper-1-biased humoral and cellular immune response in immunized mice. These data suggest that immunization with a booster dose of attenuated RB51 mutants provides an attractive strategy to protect against either bovine or canine brucellosis.

The mannosylated extracellular domain of Her2/neu produced in P. pastoris induces protective antitumor immunity

International Nuclear Information System (INIS)

Dimitriadis, Alexios; Gontinou, Chrysanthi; Baxevanis, Constantin N; Mamalaki, Avgi

2009-01-01

Her2/neu is overexpressed in various human cancers of epithelial origin and is associated with increased metastatic potential and poor prognosis. Several attempts have been made using the extracellular domain of Her2/neu (ECD/Her2) as a prophylactic vaccine in mice with no success in tumor prevention. The extracellular domain of Her2/neu (ECD/Her2) was expressed in yeast P. pastoris, in a soluble highly mannosylated form. The immune response of the immunization with this recombinant ECD/Her2 was analyzed using immunoprecipitation and western blot analysis, proliferation and cytotoxicity assays as well as specific tumor growth assays. Mannosylated ECD/Her2 elicited a humoral response with HER2/neu specific antibodies in vaccinated mice, which were able to reduce the proliferation rate of cancer cells in vitro. Moreover, it elicited a cellular response with Her2/neu-specific CTL capable of lysing tumor cells, in vitro. When immunized Balb/c and HHD mice were challenged with Her2/neu-overexpressing cells, tumor growth was inhibited. Here we report on the efficacy of the extracellular domain of human Her2/neu produced in yeast P. pastoris, which confers mannosylation of the protein, to act as a potent anti-tumor vaccine against Her2/neu overexpressing tumors. Specific cellular and humoral responses were observed as well as efficacy

Expressions of toll-like receptors 2 and 4, and relative cellular ...

African Journals Online (AJOL)

for regulation of the immune system. Their cellular factors are TNF-α, IFN-γ, IL-2, IL-6 and. IL-10. Th1 cells induce cellular response reaction and inflammatory reaction, but Th2 cell promote immunity of body fluids and resist parasitic infections; these two types of cells maintain balance in the immune system [20]. HIV infection.

Host immune cellular reactions in corneal neovascularization

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Nizar S. Abdelfattah

2016-04-01

Full Text Available Corneal neovascularization (CNV is a global important cause of visual impairment. The immune mechanisms leading to corneal heme- and lymphangiogenesis have been extensively studied over the past years as more attempts were made to develop better prophylactic and therapeutic measures. This article aims to discuss immune cells of particular relevance to CNV, with a focus on macrophages, Th17 cells, dendritic cells and the underlying immunology of common pathologies involving neovascularization of the cornea. Hopefully, a thorough understanding of these topics would propel the efforts to halt the detrimental effects of CNV.

Short-term stress enhances cellular immunity and increases early resistance to squamous cell carcinoma.

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Dhabhar, Firdaus S; Saul, Alison N; Daugherty, Christine; Holmes, Tyson H; Bouley, Donna M; Oberyszyn, Tatiana M

2010-01-01

In contrast to chronic/long-term stress that suppresses/dysregulates immune function, an acute/short-term fight-or-flight stress response experienced during immune activation can enhance innate and adaptive immunity. Moderate ultraviolet-B (UV) exposure provides a non-invasive system for studying the naturalistic emergence, progression and regression of squamous cell carcinoma (SCC). Because SCC is an immunoresponsive cancer, we hypothesized that short-term stress experienced before UV exposure would enhance protective immunity and increase resistance to SCC. Control and short-term stress groups were treated identically except that the short-term stress group was restrained (2.5h) before each of nine UV-exposure sessions (minimum erythemal dose, 3-times/week) during weeks 4-6 of the 10-week UV exposure protocol. Tumors were measured weekly, and tissue collected at weeks 7, 20, and 32. Chemokine and cytokine gene expression was quantified by real-time PCR, and CD4+ and CD8+ T cells by flow cytometry and immunohistochemistry. Compared to controls, the short-term stress group showed greater cutaneous T-cell attracting chemokine (CTACK)/CCL27, RANTES, IL-12, and IFN-gamma gene expression at weeks 7, 20, and 32, higher skin infiltrating T cell numbers (weeks 7 and 20), lower tumor incidence (weeks 11-20) and fewer tumors (weeks 11-26). These results suggest that activation of short-term stress physiology increased chemokine expression and T cell trafficking and/or function during/following UV exposure, and enhanced Type 1 cytokine-driven cell-mediated immunity that is crucial for resistance to SCC. Therefore, the physiological fight-or-flight stress response and its adjuvant-like immuno-enhancing effects, may provide a novel and important mechanism for enhancing immune system mediated tumor-detection/elimination that merits further investigation.

Protective efficacy of a single immunization with capripoxvirus-vectored recombinant peste des petits ruminants vaccines in presence of pre-existing immunity.

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Caufour, Philippe; Rufael, Tesfaye; Lamien, Charles Euloge; Lancelot, Renaud; Kidane, Menbere; Awel, Dino; Sertse, Tefera; Kwiatek, Olivier; Libeau, Geneviève; Sahle, Mesfin; Diallo, Adama; Albina, Emmanuel

2014-06-24

Sheeppox, goatpox and peste des petits ruminants (PPR) are highly contagious ruminant diseases widely distributed in Africa, the Middle East and Asia. Capripoxvirus (CPV)-vectored recombinant PPR vaccines (rCPV-PPR vaccines), which have been developed and shown to protect against both Capripox (CP) and PPR, would be critical tools in the control of these important diseases. In most parts of the world, these disease distributions overlap each other leaving concerns about the potential impact that pre-existing immunity against either disease may have on the protective efficacy of these bivalent rCPV-PPR vaccines. Currently, this question has not been indisputably addressed. Therefore, we undertook this study, under experimental conditions designed for the context of mass vaccination campaigns of small ruminants, using the two CPV recombinants (Kenya sheep-1 (KS-1) strain-based constructs) developed previously in our laboratory. Pre-existing immunity was first induced by immunization either with an attenuated CPV vaccine strain (KS-1) or the attenuated PPRV vaccine strain (Nigeria 75/1) and animals were thereafter inoculated once subcutaneously with a mixture of CPV recombinants expressing either the hemagglutinin (H) or the fusion (F) protein gene of PPRV (10(3) TCID50/animal of each). Finally, these animals were challenged with a virulent CPV strain followed by a virulent PPRV strain 3 weeks later. Our study demonstrated full protection against CP for vaccinated animals with prior exposure to PPRV and a partial protection against PPR for vaccinated animals with prior exposure to CPV. The latter animals exhibited a mild clinical form of PPR and did not show any post-challenge anamnestic neutralizing antibody response against PPRV. The implications of these results are discussed herein and suggestions made for future research regarding the development of CPV-vectored vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

Distinctive cellular immunity in genetically susceptible BALB/c mice recovered from Leishmania major infection or after subcutaneous immunization with killed parasites

International Nuclear Information System (INIS)

Liew, F.Y.; Dhaliwal, J.S.

1987-01-01

Genetically susceptible BALB/c mice are refractory to further infection after recovery from Leishmania major infection after a sublethal dose of gamma-irradiation. In contrast, mice immunized with killed promastigotes s.c. develop exacerbated lesions after infection. Both groups of mice produce only a low level of specific antibody and no detectable cytotoxic T cells, but do have a strong antigen-specific DTH, which is adoptively transferable with Lyt-1+2-, L3T4+ T cells. Kinetic and histological studies revealed that mice immunized s.c. developed Jones-Mote hypersensitivity, peaking at 15 hr. with little mononuclear cell infiltration at the site of antigen administration; whereas mice that had recovered from infection developed tuberculin-type of reactivity, peaking at 24 to 48 hr, with intense mononuclear cell infiltration. Splenic T cells from recovered mice, when injected into the footpads of normal recipients together with live promastigotes, were able to retard lesion development; whereas T cells from s.c. immunized mice, when similarly transferred, accelerated disease progression. Antigen-specific culture supernatant of spleen cells from recovered mice also activated normal resident peritoneal macrophages to kill intracellular L. major amastigotes and tumor cells. Culture supernatants of spleen cells from s.c. immunized or normal mice were devoid of such activities. Part of the macrophage-activating potential can be inhibited by antibody specific for IFN-gamma. These results therefore demonstrate that whereas the Jones-Mote reaction is correlated with disease exacerbation, the tuberculin-type of DTH may be protective. Furthermore, in vivo immunity is directly related to the capacity of T cells to produce macrophage-activating factor

Cold-adapted influenza and recombinant adenovirus vaccines induce cross-protective immunity against pH1N1 challenge in mice.

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Mark R Soboleski

Full Text Available The rapid spread of the 2009 H1N1 pandemic influenza virus (pH1N1 highlighted problems associated with relying on strain-matched vaccines. A lengthy process of strain identification, manufacture, and testing is required for current strain-matched vaccines and delays vaccine availability. Vaccines inducing immunity to conserved viral proteins could be manufactured and tested in advance and provide cross-protection against novel influenza viruses until strain-matched vaccines became available. Here we test two prototype vaccines for cross-protection against the recent pandemic virus.BALB/c and C57BL/6 mice were intranasally immunized with a single dose of cold-adapted (ca influenza viruses from 1977 or recombinant adenoviruses (rAd expressing 1934 nucleoprotein (NP and consensus matrix 2 (M2 (NP+M2-rAd. Antibodies against the M2 ectodomain (M2e were seen in NP+M2-rAd immunized BALB/c but not C57BL/6 mice, and cross-reacted with pH1N1 M2e. The ca-immunized mice did not develop antibodies against M2e. Despite sequence differences between vaccine and challenge virus NP and M2e epitopes, extensive cross-reactivity of lung T cells with pH1N1 peptides was detected following immunization. Both ca and NP+M2-rAd immunization protected BALB/c and C57BL/6 mice against challenge with a mouse-adapted pH1N1 virus.Cross-protective vaccines such as NP+M2-rAd and ca virus are effective against pH1N1 challenge within 3 weeks of immunization. Protection was not dependent on recognition of the highly variable external viral proteins and could be achieved with a single vaccine dose. The rAd vaccine was superior to the ca vaccine by certain measures, justifying continued investigation of this experimental vaccine even though ca vaccine is already available. This study highlights the potential for cross-protective vaccines as a public health option early in an influenza pandemic.

Chimeric Antigen Receptor-Engineered NK-92 Cells: An Off-the-Shelf Cellular Therapeutic for Targeted Elimination of Cancer Cells and Induction of Protective Antitumor Immunity

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Congcong Zhang

2017-05-01

Full Text Available Significant progress has been made in recent years toward realizing the potential of natural killer (NK cells for cancer immunotherapy. NK cells can respond rapidly to transformed and stressed cells and have the intrinsic potential to extravasate and reach their targets in almost all body tissues. In addition to donor-derived primary NK cells, also the established NK cell line NK-92 is being developed for adoptive immunotherapy, and general safety of infusion of irradiated NK-92 cells has been established in phase I clinical trials with clinical responses observed in some of the cancer patients treated. To enhance their therapeutic utility, NK-92 cells have been modified to express chimeric antigen receptors (CARs composed of a tumor-specific single chain fragment variable antibody fragment fused via hinge and transmembrane regions to intracellular signaling moieties such as CD3ζ or composite signaling domains containing a costimulatory protein together with CD3ζ. CAR-mediated activation of NK cells then bypasses inhibitory signals and overcomes NK resistance of tumor cells. In contrast to primary NK cells, CAR-engineered NK-92 cell lines suitable for clinical development can be established from molecularly and functionally well-characterized single cell clones following good manufacturing practice-compliant procedures. In preclinical in vitro and in vivo models, potent antitumor activity of NK-92 variants targeted to differentiation antigens expressed by hematologic malignancies, and overexpressed or mutated self-antigens associated with solid tumors has been found, encouraging further development of CAR-engineered NK-92 cells. Importantly, in syngeneic mouse tumor models, induction of endogenous antitumor immunity after treatment with CAR-expressing NK-92 cells has been demonstrated, resulting in cures and long-lasting immunological memory protecting against tumor rechallenge at distant sites. Here, we summarize the current status and future

T cell immunity to influenza in older adults: A pathophysiological framework for development of more effective vaccines

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Janet E McElhaney

2016-02-01

Full Text Available One of the most profound public health consequences of immune senescence is reflected in an increased susceptibility to influenza and other acute respiratory illnesses, as well as a loss of influenza vaccine effectiveness in older people. Common medical conditions and mental and psychosocial health issues as well as degree of frailty and functional dependence accelerate changes associated with immune senescence. All contribute to the increased risk for complications of influenza infection including pneumonias, heart diseases and strokes that lead to hospitalization, disability and death in the over 65 population. Changes in mucosal barrier mechanisms and both innate and adaptive immune functions converge in the reduced response to influenza infection, and lead to a loss of antibody-mediated protection against influenza with age. The interactions of immune senescence and reduced adaptive immune responses, persistent cytomegalovirus infection, inflammaging (chronic elevation of inflammatory cytokines, and dysregulated cytokine production, pose major challenges to the development of vaccines designed to improve T-cell mediated immunity. In older adults, the goal of vaccination is more realistically targeted to providing clinical protection against disease rather than to inducing sterilizing immunity to infection. Standard assays of antibody titres correlate with protection against influenza illness but do not detect important changes in cellular immune mechanisms that correlate with vaccine-mediated protection against influenza in older people. This article will discuss: i the burden of influenza in older adults and how this relates to changes in T cell function, ii age-related changes in different T cell subsets and immunologic targets for improved influenza vaccine efficacy in older, and iii the development of correlates of clinical protection against influenza disease to expedite the process of new vaccine development for the 65 and older

Evaluation of Protective Immune Responses Induced by Recombinant TrxLp and ENO2 Proteins against Toxoplasma gondii Infection in BALB/c Mice

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Meng Wang

2016-01-01

Full Text Available Toxoplasma gondii is an obligate intracellular parasitic protozoan that can infect almost all species of warm-blooded animals. As any chemical-based drugs could not act against the tissue cyst stage of T. gondii, vaccination may be one of the ideal control strategies. In the present study, two new vaccine candidates, named TgENO2 and TgTrxLp, were purified from Escherichia coli with pET-30a(+ expression system and then were injected into BALB/c mice to evaluate the protective efficacy against acute and chronic toxoplasmosis. The results showed that both the recombinant proteins, either alone or in combination, could elicit strong humoral and cellular immune responses with a higher level of IgG antibodies, IFN-γ, IL-2, CD4+, and CD8+ T cells as compared to those in mice from control groups. After acute challenge with tachyzoites of the GJS strain, mice immunized with rTgTrxLp (8±2.77 d, rTgENO2 (7.4±1.81 d, and rTgTrxLp + rTgENO2 (8.38±4.57 d proteins showed significantly longer survival time than those that received Freund’s adjuvant (6.78±2.08 d and PBS (6.38±4.65 d (χ2 = 9.687, df = 4, P=0.046. The protective immunity of rTgTrxLp, rTgENO2, and rTgTrxLp + rTgENO2 proteins against chronic T. gondii infection showed 69.77%, 58.14%, and 20.93% brain cyst reduction as compared to mice that received PBS. The present study suggested that both TgENO2 and TgTrxLp were potential candidates for the development of multicomponent vaccines against toxoplasmosis.

Use of radioactive double labelling technique in the chemical analysis of the mediators of cellular immunity

International Nuclear Information System (INIS)

Sorg, C.

1978-01-01

Radioactive double labelling was adapted for the analysis of mediators of cellular immunity. Two identical lymphocyte cultures were simultaneously labelled with [ 3 H]- or [ 14 C] leucine. Each of the cultures was stimulated with antigen or mitogen. The combined supernatants were then subjected to various fractionation procedures. By determining the isotope ratio in each fraction it is possible to identify those products of activated lymphocytes that have been produced either de novo or in increased amounts. The method proved sensitive enough to detect lymphocyte activation products in supernatants of activated lymphocyte cultures from guinea pig, mouse, and man

Cellular Immune Reactions of the Sunn Pest, Eurygaster integriceps, to the Entomopathogenic Fungus, Beauveria bassiana and Its Secondary Metabolites

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Zibaee, Arash; Bandani, Ali Reza; Talaei-Hassanlouei, Reza; Malagoli, Davide

2011-01-01

In this study, five morphological types of circulating hemocytes were recognized in the hemolymph of the adult sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), namely prohemocytes, plasmatocytes, granulocytes, adipohemocytes, and oenocytoids. The effects of the secondary metabolites of the entomopathogenic fungus Beauveria bassiana on cellular immune defenses of Eurygaster integriceps were investigated. The results showed that the fungal secondary metabolites inhibited phagocytic activity of E. integriceps hemocytes and hampered nodule formation. A reduction of phenoloxidase activity was also observed. The data suggest that B. bassiana produce secondary metabolites that disable several immune mechanisms allowing the fungus to overcome and then kill its host. This characteristic makes B. bassiana a promising model for biological control of insect pests such as E. integriceps. PMID:22233481

Comparative evaluation of oral and intranasal priming with replication-competent adenovirus 5 host range mutant (Ad5hr)-simian immunodeficiency virus (SIV) recombinant vaccines on immunogenicity and protective efficacy against SIV(mac251).

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Zhou, Qifeng; Hidajat, Rachmat; Peng, Bo; Venzon, David; Aldrich, M Kristine; Richardson, Ersell; Lee, Eun Mi; Kalyanaraman, V S; Grimes, George; Gómez-Román, V Raúl; Summers, L Ebonita; Malkevich, Nina; Robert-Guroff, Marjorie

2007-11-19

Oral, replication-competent Ad-HIV vaccines are advancing to human trials. Previous evaluation of protective efficacy in non-human primates has primarily followed upper respiratory tract administrations. Here we compared sequential oral (O/O) versus intranasal/oral (I/O) priming of rhesus macaques with Ad5 host range mutant-SIV recombinants expressing SIV env/rev, gag, and nef genes followed by boosting with SIV gp120 protein. Cellular immune responses in PBMC were stronger and more frequent after I/O administration. Both groups developed mucosal immunity, including memory cells in bronchial alveolar lavage, and gut-homing receptors on PBMC. Following intrarectal SIV(mac251) challenge, both groups exhibited equivalent, significant protection and robust post-challenge cellular immunity. Our results illustrate the promise of oral replication-competent Ad-recombinant vaccines. Pre-challenge PBMC ELISPOT and proliferative responses did not predict protection in the O/O group, highlighting the need for simple, non-invasive methods to reliably assess mucosal immunity.

Innate lymphoid cells: models of plasticity for immune homeostasis and rapid responsiveness in protection.

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Almeida, F F; Belz, G T

2016-09-01

Innate lymphoid cells (ILCs) have stormed onto the immune landscape as "newly discovered" cell types. These tissue-resident sentinels are enriched at mucosal surfaces and engage in complex cross talk with elements of the adaptive immune system and microenvironment to orchestrate immune homeostasis. Many parallels exist between innate cells and T cells leading to the initial partitioning of ILCs into rather rigid subsets that reflect their "adaptive-like" effector cytokines profiles. ILCs themselves, however, have unique attributes that are only just beginning to be elucidated. These features result in complementarity with, rather than complete duplication of, functions of the adaptive immune system. Key transcription factors determine the pathway of differentiation of progenitors towards an ILC1, ILC2, or ILC3 subset. Once formed, flexibility in the responses of these subsets to stimuli unexpectedly allows transdifferentation between the different subsets and the acquisition of altered phenotypes and function. This provides a mechanism for rapid innate immune responsiveness. Here, we discuss the models of differentiation for maintenance and activation of tissue-resident ILCs in maintaining immune homeostasis and protection.

Evaluation of Different Parameters of Humoral and Cellular Immune Responses in HIV Serodiscordant Heterosexual Couples: Humoral Response Potentially Implicated in Modulating Transmission Rates

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María Julia Ruiz

2017-12-01

Full Text Available As the HIV/AIDS pandemic still progresses, understanding the mechanisms governing viral transmission as well as protection from HIV acquisition is fundamental. In this context, cohorts of HIV serodiscordant heterosexual couples (SDC represent a unique tool. The present study was aimed to evaluate specific parameters of innate, cellular and humoral immune responses in SDC. Specifically, plasma levels of cytokines and chemokines, HIV-specific T-cell responses, gp120-specific IgG and IgA antibodies, and HIV-specific antibody-dependent cellular cytotoxicity (ADCC activity were assessed in nine HIV-exposed seronegative individuals (ESN and their corresponding HIV seropositive partners (HIV+-P, in eighteen chronically infected HIV subjects (C, nine chronically infected subjects known to be HIV transmitters (CT and ten healthy HIV− donors (HD. Very low magnitude HIV-specific cellular responses were found in two out of six ESN. Interestingly, HIV+-P had the highest ADCC magnitude, the lowest IgA levels and the highest IgG/IgA ratio, all compared to CT. Positive correlations between CD4+ T-cell counts and both IgG/IgA ratios and %ADCC killing uniquely distinguished HIV+-P. Additionally, evidence of IgA interference with ADCC responses from HIV+-P and CT is provided. These data suggest for the first time a potential role of ADCC and/or gp120-specific IgG/IgA balance in modulating heterosexual transmission. In sum, this study provides key information to understand the host factors that influence viral transmission, which should be considered in both the development of prophylactic vaccines and novel immunotherapies for HIV-1 infection.

Quantitating cellular immune responses to cancer vaccines.

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Lyerly, H Kim

2003-06-01

While the future of immunotherapy in the treatment of cancer is promising, it is difficult to compare the various approaches because monitoring assays have not been standardized in approach or technique. Common assays for measuring the immune response need to be established so that these assays can one day serve as surrogate markers for clinical response. Assays that accurately detect and quantitate T-cell-mediated, antigen-specific immune responses are particularly desired. However, to date, increases in the number of cytotoxic T cells through immunization have not been correlated with clinical tumor regression. Ideally, then, a T-cell assay not only needs to be sensitive, specific, reliable, reproducible, simple, and quick to perform, it must also demonstrate close correlation with clinical outcome. Assays currently used to measure T-cell response are delayed-type hypersensitivity testing, flow cytometry using peptide major histocompatibility complex tetramers, lymphoproliferation assay, enzyme-linked immunosorbant assay, enzyme-linked immunospot assay, cytokine flow cytometry, direct cytotoxicity assay, measurement of cytokine mRNA by quantitative reverse transcriptase polymerase chain reaction, and limiting dilution analysis. The purpose of this review is to describe the attributes of each test and compare their advantages and disadvantages.

Resistance and Protective Immunity in Redfish Lake Sockeye Salmon Exposed to M Type Infectious Hematopoietic Necrosis Virus (IHNV)

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Kurath, Gael; Garver, Kyle; Purcell, Maureen K.; LaPatra, Scott E.

2010-01-01

Differential virulence of infectious hematopoietic necrosis virus (IHNV) isolates from the U and M phylogenetic subgroups is clearly evident in the Redfish Lake (RFL) strain of sockeye salmon Oncorhynchus nerka. In these fish, experimental immersion challenges with U isolates cause extremely high mortality and M isolates cause low or no mortality. When survivors of M virus immersion challenges were exposed to a secondary challenge with virulent U type virus they experienced high mortality, indicating that the primary M challenge did not elicit protective immunity. Delivery of a moderate dose (2 × 104 plaque-forming units [PFU]/fish) of virus by intraperitoneal injection challenge did not overcome RFL sockeye salmon resistance to M type IHNV. Injection challenge with a high dose (5 × 106 PFU/fish) of M type virus caused 10% mortality, and in this case survivors did develop protective immunity against a secondary U type virus challenge. Thus, although it is possible for M type IHNV to elicit cross-protective immunity in this disease model, it does not develop after immersion challenge despite entry, transient replication of M virus to low levels, stimulation of innate immune genes, and development of neutralizing antibodies in some fish.

Impact of aging immune system on neurodegeneration and potential immunotherapies.

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Liang, Zhanfeng; Zhao, Yang; Ruan, Linhui; Zhu, Linnan; Jin, Kunlin; Zhuge, Qichuan; Su, Dong-Ming; Zhao, Yong

2017-10-01

The interaction between the nervous and immune systems during aging is an area of avid interest, but many aspects remain unclear. This is due, not only to the complexity of the aging process, but also to a mutual dependency and reciprocal causation of alterations and diseases between both the nervous and immune systems. Aging of the brain drives whole body systemic aging, including aging-related changes of the immune system. In turn, the immune system aging, particularly immunosenescence and T cell aging initiated by thymic involution that are sources of chronic inflammation in the elderly (termed inflammaging), potentially induces brain aging and memory loss in a reciprocal manner. Therefore, immunotherapeutics including modulation of inflammation, vaccination, cellular immune therapies and "protective autoimmunity" provide promising approaches to rejuvenate neuroinflammatory disorders and repair brain injury. In this review, we summarize recent discoveries linking the aging immune system with the development of neurodegeneration. Additionally, we discuss potential rejuvenation strategies, focusing aimed at targeting the aging immune system in an effort to prevent acute brain injury and chronic neurodegeneration during aging. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cigarette smoke-exposed saliva suppresses cellular and humoral immune responses in an animal model

International Nuclear Information System (INIS)

Jafarzadeh, A.; Bakhshi, H.; Rezayati, M.T.; Nemati, M.

2009-01-01

To evaluate the effects of cigarette smoke (CS)-exposed saliva on cellular and antibody responses in an animal model. The stimulatory and non-stimulatory saliva samples were collected from 10 healthy subjects and were then exposed to CS for 20 or 80 minutes. The CS-exposed saliva samples were administrated intraperitoneally (i.p) to male Balb/c mice. Then the delayed type hypersensitivity (DTH) and antibody responses to sheep red blood cell (SRBC) was assessed. Moreover, the total white blood cells (WBC) counts and the blood lymphocytes counts were determined. The mean of DTH responses of animal groups received 20 minutes or 80 minutes CS-exposed saliva samples was significantly lower than that observed in control group. Moreover, The mean titer of anti-SRBC antibody was significantly lower in animal groups who received 80 minutes CS-exposed stimulatory or non-stimulatory saliva as compared to control group (P<0.04 and P<0.002, respectively). The mean counts of blood lymphocytes in 80 minutes CS exposed-stimulatory saliva group was also significantly lower as compared to control group (P<0.05). These results show that the CS-exposed saliva samples have profound suppressive effects on both cellular and humoral immune response in a mouse animal model (JPMA 59:760; 2009). (author)

Can the Immune System Perform a t-Test?

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Faria, Bruno Filipe; Mostardinha, Patricia

2017-01-01

The self-nonself discrimination hypothesis remains a landmark concept in immunology. It proposes that tolerance breaks down in the presence of nonself antigens. In strike contrast, in statistics, occurrence of nonself elements in a sample (i.e., outliers) is not obligatory to violate the null hypothesis. Very often, what is crucial is the combination of (self) elements in a sample. The two views on how to detect a change seem challengingly different and it could seem difficult to conceive how immunological cellular interactions could trigger responses with a precision comparable to some statistical tests. Here it is shown that frustrated cellular interactions reconcile the two views within a plausible immunological setting. It is proposed that the adaptive immune system can be promptly activated either when nonself ligands are detected or self-ligands occur in abnormal combinations. In particular we show that cellular populations behaving in this way could perform location statistical tests, with performances comparable to t or KS tests, or even more general data mining tests such as support vector machines or random forests. In more general terms, this work claims that plausible immunological models should provide accurate detection mechanisms for host protection and, furthermore, that investigation on mechanisms leading to improved detection in “in silico” models can help unveil how the real immune system works. PMID:28046042

Involvement of CD8+ T cell-mediated immune responses in LcrV DNA vaccine induced protection against lethal Yersinia pestis challenge.

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Wang, Shixia; Goguen, Jon D; Li, Fusheng; Lu, Shan

2011-09-09

Yersinia pestis (Y. pestis) is the causative pathogen of plague, a highly fatal disease for which an effective vaccine, especially against mucosal transmission, is still not available. Like many bacterial infections, antigen-specific antibody responses have been traditionally considered critical, if not solely responsible, for vaccine-induced protection against Y. pestis. Studies in recent years have suggested the importance of T cell immune responses against Y. pestis infection but information is still limited about the details of Y. pestis antigen-specific T cell immune responses. In current report, studies are conducted to identify the presence of CD8+ T cell epitopes in LcrV protein, the leading antigen of plague vaccine development. Furthermore, depletion of CD8+ T cells in LcrV DNA vaccinated Balb/C mice led to reduced protection against lethal intranasal challenge of Y. pestis. These findings establish that an LcrV DNA vaccine is able to elicit CD8+ T cell immune responses against specific epitopes of this key plague antigen and that a CD8+ T cell immune response is involved in LcrV DNA vaccine-elicited protection. Future studies in plague vaccine development will need to examine if the presence of detectable T cell immune responses, in particular CD8+ T-cell immune responses, will enhance the protection against Y. pestis in higher animal species or humans. Copyright © 2010 Elsevier Ltd. All rights reserved.

The cellular memory disc of reprogrammed cells.

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Anjamrooz, Seyed Hadi

2013-04-01

The crucial facts underlying the low efficiency of cellular reprogramming are poorly understood. Cellular reprogramming occurs in nuclear transfer, induced pluripotent stem cell (iPSC) formation, cell fusion, and lineage-switching experiments. Despite these advances, there are three fundamental problems to be addressed: (1) the majority of cells cannot be reprogrammed, (2) the efficiency of reprogramming cells is usually low, and (3) the reprogrammed cells developed from a patient's own cells activate immune responses. These shortcomings present major obstacles for using reprogramming approaches in customised cell therapy. In this Perspective, the author synthesises past and present observations in the field of cellular reprogramming to propose a theoretical picture of the cellular memory disc. The current hypothesis is that all cells undergo an endogenous and exogenous holographic memorisation such that parts of the cellular memory dramatically decrease the efficiency of reprogramming cells, act like a barrier against reprogramming in the majority of cells, and activate immune responses. Accordingly, the focus of this review is mainly to describe the cellular memory disc (CMD). Based on the present theory, cellular memory includes three parts: a reprogramming-resistance memory (RRM), a switch-promoting memory (SPM) and a culture-induced memory (CIM). The cellular memory arises genetically, epigenetically and non-genetically and affects cellular behaviours. [corrected].

An initial examination of the potential role of T-cell immunity in protection against feline immunodeficiency virus (FIV) infection.

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Aranyos, Alek M; Roff, Shannon R; Pu, Ruiyu; Owen, Jennifer L; Coleman, James K; Yamamoto, Janet K

2016-03-14

The importance of vaccine-induced T-cell immunity in conferring protection with prototype and commercial FIV vaccines is still unclear. Current studies performed adoptive transfer of T cells from prototype FIV-vaccinated cats to partial-to-complete feline leukocyte antigen (FLA)-matched cats a day before either homologous FIVPet or heterologous-subtype pathogenic FIVFC1 challenge. Adoptive-transfer (A-T) conferred a protection rate of 87% (13 of 15, p 13 × 10(6) cells were required for A-T protection against FIVFC1 strain, reported to be a highly pathogenic virus resistant to vaccine-induced neutralizing-antibodies. The addition of FLA-matched B cells alone was not protective. The poor quality of the anti-FIV T-cell immunity induced by the vaccine likely contributed to the lack of protection in an FLA-matched recipient against FIVFC1. The quality of the immune response was determined by the presence of high mRNA levels of cytolysin (perforin) and cytotoxins (granzymes A, B, and H) and T helper-1 cytokines (interferon-γ [IFNγ] and IL2). Increased cytokine, cytolysin and cytotoxin production was detected in the donors which conferred protection in A-T studies. In addition, the CD4(+) and CD8(+) T-cell proliferation and/or IFNγ responses to FIV p24 and reverse transcriptase increased with each year in cats receiving 1X-3X vaccine boosts over 4 years. These studies demonstrate that anti-FIV T-cell immunity induced by vaccination with a dual-subtype FIV vaccine is essential for prophylactic protection against AIDS lentiviruses such as FIV and potentially HIV-1. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immunization with plasmid DNA encoding the hemagglutinin and the nucleoprotein confers robust protection against a lethal canine distemper virus challenge.

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Dahl, Lotte; Jensen, Trine Hammer; Gottschalck, Elisabeth; Karlskov-Mortensen, Peter; Jensen, Tove Dannemann; Nielsen, Line; Andersen, Mads Klindt; Buckland, Robin; Wild, T Fabian; Blixenkrone-Møller, Merete

2004-09-09

We have investigated the protective effect of immunization of a highly susceptible natural host of canine distemper virus (CDV) with DNA plasmids encoding the viral nucleoprotein (N) and hemagglutinin (H). The combined intradermal and intramuscular routes of immunization elicited high virus-neutralizing serum antibody titres in mink (Mustela vison). To mimic natural exposure, we also conducted challenge infection by horizontal transmission from infected contact animals. Other groups received a lethal challenge infection by administration to the mucosae of the respiratory tract and into the muscle. One of the mink vaccinated with N plasmid alone developed severe disease after challenge. In contrast, vaccination with the H plasmid together with the N plasmid conferred solid protection against disease and we were unable to detect CDV infection in PBMCs or in different tissues after challenge. Our findings show that DNA immunization by the combined intradermal and intramuscular routes can confer solid protective immunity against naturally transmitted morbillivirus infection and disease.

The cellular immune system in myelomagenesis: NK cells and T cells in the development of MM and their uses in immunotherapies

International Nuclear Information System (INIS)

Dosani, T; Carlsten, M; Maric, I; Landgren, O

2015-01-01

As vast strides are being made in the management and treatment of multiple myeloma (MM), recent interests are increasingly focusing on understanding the development of the disease. The knowledge that MM develops exclusively from a protracted phase of monoclonal gammopathy of undetermined significance provides an opportunity to study tumor evolution in this process. Although the immune system has been implicated in the development of MM, the scientific literature on the role and status of various immune components in this process is broad and sometimes contradictory. Accordingly, we present a review of cellular immune subsets in myelomagenesis. We summarize the current literature on the quantitative and functional profiles of natural killer cells and T-cells, including conventional T-cells, natural killer T-cells, γδ T-cells and regulatory T-cells, in myelomagenesis. Our goal is to provide an overview of the status and function of these immune cells in both the peripheral blood and the bone marrow during myelomagenesis. This provides a better understanding of the nature of the immune system in tumor evolution, the knowledge of which is especially significant considering that immunotherapies are increasingly being explored in the treatment of both MM and its precursor conditions

Humoral and In Vivo Cellular Immunity against the Raw Insect-Derived Recombinant Leishmania infantum Antigens KMPII, TRYP, LACK, and papLe22 in Dogs from an Endemic Area

Science.gov (United States)

Todolí, Felicitat; Solano-Gallego, Laia; de Juan, Rafael; Morell, Pere; del Carmen Núñez, Maria; Lasa, Rodrigo; Gómez-Sebastián, Silvia; Escribano, José M.; Alberola, Jordi; Rodríguez-Cortés, Alhelí

2010-01-01

Leishmania infantum causes visceral leishmaniasis, a severe zoonotic and systemic disease that is fatal if left untreated. Identification of the antigens involved in Leishmania-specific protective immune response is a research priority for the development of effective control measures. For this purpose, we evaluated, in 27 dogs from an enzootic zone, specific humoral and cellular immune response by delayed-type hypersensitivity (DTH) skin test both against total L. infantum antigen and the raw Trichoplusia ni insect-derived kinetoplastid membrane protein-11 (rKMPII), tryparedoxin peroxidase (rTRYP), Leishmania homologue of receptors for activated C kinase (rLACK), and 22-kDa potentially aggravating protein of Leishmania (rpapLe22) antigens from this parasite. rTRYP induced the highest number of positive DTH responses (55% of leishmanin skin test [LST]-positive dogs), showing that TRYP antigen is an important T cell immunogen, and it could be a promising vaccine candidate against this disease. When TRYP-DTH and KMPII-DTH tests were evaluated in parallel, 82% of LST-positive dogs were detected, suggesting that both antigens could be considered as components of a standardized DTH immunodiagnostic tool for dogs. PMID:21118936

Azadirachtin-induced effects on various life history traits and cellular immune reactions of Galleria mellonella (Lepidoptera: Pyralidae

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Er Aylin

2017-01-01

Full Text Available The effects of the botanical insecticide azadirachtin were examined on the life history traits, fecundity and immune parameters of Galleria mellonella L. (Lepidoptera: Pyralidae. We determined that for the topical application of azadirachtin, the LC50 was 16.564 ppm; at 100 ppm the adult emergence time was prolonged, however the longevity of adults remained unchanged above sublethal concentrations. The mean number of healthy eggs and the fecundity of adults decreased, whereas the number of defective eggs increased with azadirachtin treatment. At concentrations >50 ppm female G. mellonella adults laid no eggs. Azadirachtin reduced total hemocyte counts at 24 and 48 h posttreatment, however the alterations in differential hemocyte counts were only significant at 100 ppm. Laminarin-induced nodulation response and the spreading ability of hemocytes were also suppressed with azadirachtin treatment. Our results suggest that azadirachtin, as a good candidate for integrated pest control, has the capability to affect the biological parameters and cellular immunity of the model insect G. mellonella.

Discordance of epstein-barr virus (ebv) specific humoral and cellular immunity in patients with malignant lymphomas : Elevated antibody titers and lowered invitro lymphocyte-reactivity

NARCIS (Netherlands)

ten Napel, C. H. H.; The, T. Hauw; van Egten-Bijker, J; de Gast, G. C.; Halie, M. R.; Langenhuysen, M. M. A. C.

1978-01-01

The relationship between specific viral cellular and humoral immunity to the Epstein–Barr Virus (EBV) was investigated in thirty-one untreated patients with malignant lymphoma (ML) and sex- and age-matched controls. In vitro reactivity of peripheral blood lymphocytes to heatinactivated purified EBV,

Intranasal immunization of baculovirus displayed hemagglutinin confers complete protection against mouse adapted highly pathogenic H7N7 reassortant influenza virus.

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Subaschandrabose Rajesh Kumar

Full Text Available BACKGROUND: Avian influenza A H7N7 virus poses a pandemic threat to human health because of its ability for direct transmission from domestic poultry to humans and from human to human. The wide zoonotic potential of H7N7 combined with an antiviral immunity inhibition similar to pandemic 1918 H1N1 and 2009 H1N1 influenza viruses is disconcerting and increases the risk of a putative H7N7 pandemic in the future, underlining the urgent need for vaccine development against this virus. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we developed a recombinant vaccine by expressing the H7N7-HA protein on the surface of baculovirus (Bac-HA. The protective efficacy of the live Bac-HA vaccine construct was evaluated in a mouse model by challenging mice immunized intranasally (i.n. or subcutaneously (s.c. with high pathogenic mouse adapted H7N7 reassorted strain. Although s.c. injection of live Bac-HA induced higher specific IgG than i.n. immunization, the later resulted in an elevated neutralization titer. Interestingly, 100% protection from the lethal viral challenge was only observed for the mice immunized intranasally with live Bac-HA, whereas no protection was achieved in any other s.c. or i.n. immunized mice groups. In addition, we also observed higher mucosal IgA as well as increased IFN-γ and IL-4 responses in the splenocytes of the surviving mice coupled with a reduced viral titer and diminished histopathological signs in the lungs. CONCLUSION: Our results indicated that protection from high pathogenic H7N7 (NL/219/03 virus requires both mucosal and systemic immune responses in mice. The balance between Th1 and Th2 cytokines is also required for the protection against the H7N7 pathogen. Intranasal administration of live Bac-HA induced all these immune responses and protected the mice from lethal viral challenge. Therefore, live Bac-HA is an effective vaccine candidate against H7N7 viral infections.

Bovine immune response to inoculation with Neospora caninum surface antigen SRS2 lipopeptides mimics immune response to infection with live parasites.

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Baszler, Timothy V; Shkap, Varda; Mwangi, Waithaka; Davies, Christopher J; Mathison, Bruce A; Mazuz, Monica; Resnikov, Dror; Fish, Lea; Leibovitch, Benjamin; Staska, Lauren M; Savitsky, Igor

2008-04-01

Infection of cattle with Neospora caninum protozoa, the causative agent of bovine protozoal abortion, results in robust cellular and humoral immune responses, particularly CD4(+) T-lymphocyte activation and gamma interferon (IFN-gamma) secretion. In the present study, N. caninum SRS2 (NcSRS2) T-lymphocyte-epitope-bearing subunits were incorporated into DNA and peptide preparations to assess CD4(+) cell proliferation and IFN-gamma T-lymphocyte-secretion immune responses in cattle with predetermined major histocompatibility complex (MHC) genotypes. In order to optimize dendritic-cell processing, NcSRS2 DNA vaccine was delivered with granulocyte macrophage-colony-stimulating factor and Flt3 ligand adjuvant. The synthesized NcSRS2 peptides were coupled with a palmitic acid molecule (lipopeptide) and delivered with Freund's adjuvant. Cattle vaccinated with NcSRS2 DNA vaccine alone did not induce T-lymphocyte activation or IFN-gamma secretion, whereas subsequent booster inoculation with NcSRS2-lipopeptides induced robust NcSRS2-specific immune responses. Compared to the response in control animals, NcSRS2-lipopeptide-immunized cattle had significantly increased NcSRS2-specific T-lymphocyte proliferation, numbers of IFN-gamma-secreting peripheral blood mononuclear cells, and immunoglobulin G1 (IgG1) and IgG2a antibody levels. The findings show that N. caninum NcSRS2 subunits bearing T-lymphocyte epitopes induced cell-mediated immune responses similar to the protective immune responses previously described against live parasite infection, namely T-lymphocyte activation and IFN-gamma secretion. The findings support the investigation of NcSRS2 immunogens for protection against N. caninum-induced fetal infection and abortion in cattle.

Simultaneous approach using systemic, mucosal and transcutaneous routes of immunization for development of protective HIV-1 vaccines.

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Belyakov, I M; Ahlers, J D

2011-01-01

Mucosal tissues are major sites of HIV entry and initial infection. Induction of a local mucosal cytotoxic T lymphocyte response is considered an important goal in developing an effective HIV vaccine. In addition, activation and recruitment of memory CD4(+) and CD8(+) T cells in systemic lymphoid circulation to mucosal effector sites might provide the firewall needed to prevent virus spread. Therefore a vaccine that generates CD4(+) and CD8(+) responses in both mucosal and systemic tissues might be required for protection against HIV. However, optimal routes and number of vaccinations required for the generation of long lasting CD4(+) and CD8(+) CTL effector and memory responses are not well understood especially for mucosal T cells. A number of studies looking at protective immune responses against diverse mucosal pathogens have shown that mucosal vaccination is necessary to induce a compartmentalized immune response including maximum levels of mucosal high-avidity CD8(+) CTL, antigen specific mucosal antibodies titers (especially sIgA), as well as induction of innate anti-viral factors in mucosa tissue. Immune responses are detectable at mucosal sites after systemic delivery of vaccine, and prime boost regimens can amplify the magnitude of immune responses in mucosal sites and in systemic lymphoid tissues. We believe that the most optimal mucosal and systemic HIV/SIV specific protective immune responses and innate factors might best be achieved by simultaneous mucosal and systemic prime and boost vaccinations. Similar principals of vaccination may be applied for vaccine development against cancer and highly invasive pathogens that lead to chronic infection.

Comparison of the immune profile of nonhealing cutaneous Leishmaniasis patients with those with active lesions and those who have recovered from infection

DEFF Research Database (Denmark)

Ajdary, S; Alimohammadian, M H; Eslami, M B

2000-01-01

Th1-type cellular immune responses play a critical role in protection against infection with Leishmania parasites, whereas activation of Th2-type cells results in progressive disease. Cutaneous leishmaniasis caused by Leishmania major is often a self-healing disease; however, persistent nonhealing...

Cold-Adapted Influenza and Recombinant Adenovirus Vaccines Induce Cross-Protective Immunity against pH1N1 Challenge in Mice

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Soboleski, Mark R.; Gabbard, Jon D.; Price, Graeme E.; Misplon, Julia A.; Lo, Chia-Yun; Perez, Daniel R.; Ye, Jianqiang; Tompkins, S. Mark; Epstein, Suzanne L.

2011-01-01

Background The rapid spread of the 2009 H1N1 pandemic influenza virus (pH1N1) highlighted problems associated with relying on strain-matched vaccines. A lengthy process of strain identification, manufacture, and testing is required for current strain-matched vaccines and delays vaccine availability. Vaccines inducing immunity to conserved viral proteins could be manufactured and tested in advance and provide cross-protection against novel influenza viruses until strain-matched vaccines became available. Here we test two prototype vaccines for cross-protection against the recent pandemic virus. Methodology/Principal Findings BALB/c and C57BL/6 mice were intranasally immunized with a single dose of cold-adapted (ca) influenza viruses from 1977 or recombinant adenoviruses (rAd) expressing 1934 nucleoprotein (NP) and consensus matrix 2 (M2) (NP+M2-rAd). Antibodies against the M2 ectodomain (M2e) were seen in NP+M2-rAd immunized BALB/c but not C57BL/6 mice, and cross-reacted with pH1N1 M2e. The ca-immunized mice did not develop antibodies against M2e. Despite sequence differences between vaccine and challenge virus NP and M2e epitopes, extensive cross-reactivity of lung T cells with pH1N1 peptides was detected following immunization. Both ca and NP+M2-rAd immunization protected BALB/c and C57BL/6 mice against challenge with a mouse-adapted pH1N1 virus. Conclusion/Significance Cross-protective vaccines such as NP+M2-rAd and ca virus are effective against pH1N1 challenge within 3 weeks of immunization. Protection was not dependent on recognition of the highly variable external viral proteins and could be achieved with a single vaccine dose. The rAd vaccine was superior to the ca vaccine by certain measures, justifying continued investigation of this experimental vaccine even though ca vaccine is already available. This study highlights the potential for cross-protective vaccines as a public health option early in an influenza pandemic. PMID:21789196

Immunity against mouse thymus-leukemia antigen (TL) protects against development of lymphomas induced by a chemical carcinogen, N-butyl-N-nitrosourea.

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Tsujimura, Kunio; Obata, Yuichi; Matsudaira, Yasue; Ozeki, Satoshi; Taguchi, Osamu; Nishida, Keiko; Okanami, Yuko; Akatsuka, Yoshiki; Kuzushima, Kiyotaka; Takahashi, Toshitada

2004-11-01

Mouse thymus-leukemia antigens (TL) are aberrantly expressed on T lymphomas in C57BL/6 (B6) and C3H/He (C3H) mice, while they are not expressed on normal T lymphocytes in these strains. When N-butyl-N-nitrosourea (NBU), a chemical carcinogen, was administered orally to B6 and C3H strains, lymphoma development was slower than in T3(b)-TL gene-transduced counterpart strains expressing TL ubiquitously as self-antigens, suggesting that anti-TL immunity may play a protective role. In addition, the development of lymphomas was slightly slower in C3H than in B6, which seems to be in accordance with the results of skin graft experiments indicating that both cellular and humoral immunities against TL were stronger in C3H than B6 mice. The interesting finding that B lymphomas derived from a T3(b)-TL transgenic strain (C3H background) expressing a very high level of TL were rejected in C3H, but not in H-2K(b) transgenic mice (C3H background), raises the possibility that TL-specific effector T cell populations are eliminated and/or energized to a certain extent by interacting with H-2K(b) molecules.

Immune protection of nonhuman primates against Ebola virus with single low-dose adenovirus vectors encoding modified GPs.

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Nancy J Sullivan

2006-06-01

Full Text Available Ebola virus causes a hemorrhagic fever syndrome that is associated with high mortality in humans. In the absence of effective therapies for Ebola virus infection, the development of a vaccine becomes an important strategy to contain outbreaks. Immunization with DNA and/or replication-defective adenoviral vectors (rAd encoding the Ebola glycoprotein (GP and nucleoprotein (NP has been previously shown to confer specific protective immunity in nonhuman primates. GP can exert cytopathic effects on transfected cells in vitro, and multiple GP forms have been identified in nature, raising the question of which would be optimal for a human vaccine.To address this question, we have explored the efficacy of mutant GPs from multiple Ebola virus strains with reduced in vitro cytopathicity and analyzed their protective effects in the primate challenge model, with or without NP. Deletion of the GP transmembrane domain eliminated in vitro cytopathicity but reduced its protective efficacy by at least one order of magnitude. In contrast, a point mutation was identified that abolished this cytopathicity but retained immunogenicity and conferred immune protection in the absence of NP. The minimal effective rAd dose was established at 10(10 particles, two logs lower than that used previously.Expression of specific GPs alone vectored by rAd are sufficient to confer protection against lethal challenge in a relevant nonhuman primate model. Elimination of NP from the vaccine and dose reductions to 10(10 rAd particles do not diminish protection and simplify the vaccine, providing the basis for selection of a human vaccine candidate.

Immune Protection of Nonhuman Primates against Ebola Virus with Single Low-Dose Adenovirus Vectors Encoding Modified GPs

Science.gov (United States)

Geisbert, Joan B; Shedlock, Devon J; Xu, Ling; Lamoreaux, Laurie; Custers, Jerome H. H. V; Popernack, Paul M; Yang, Zhi-Yong; Pau, Maria G; Roederer, Mario; Koup, Richard A; Goudsmit, Jaap; Jahrling, Peter B; Nabel, Gary J

2006-01-01

Background Ebola virus causes a hemorrhagic fever syndrome that is associated with high mortality in humans. In the absence of effective therapies for Ebola virus infection, the development of a vaccine becomes an important strategy to contain outbreaks. Immunization with DNA and/or replication-defective adenoviral vectors (rAd) encoding the Ebola glycoprotein (GP) and nucleoprotein (NP) has been previously shown to confer specific protective immunity in nonhuman primates. GP can exert cytopathic effects on transfected cells in vitro, and multiple GP forms have been identified in nature, raising the question of which would be optimal for a human vaccine. Methods and Findings To address this question, we have explored the efficacy of mutant GPs from multiple Ebola virus strains with reduced in vitro cytopathicity and analyzed their protective effects in the primate challenge model, with or without NP. Deletion of the GP transmembrane domain eliminated in vitro cytopathicity but reduced its protective efficacy by at least one order of magnitude. In contrast, a point mutation was identified that abolished this cytopathicity but retained immunogenicity and conferred immune protection in the absence of NP. The minimal effective rAd dose was established at 1010 particles, two logs lower than that used previously. Conclusions Expression of specific GPs alone vectored by rAd are sufficient to confer protection against lethal challenge in a relevant nonhuman primate model. Elimination of NP from the vaccine and dose reductions to 1010 rAd particles do not diminish protection and simplify the vaccine, providing the basis for selection of a human vaccine candidate. PMID:16683867

Roles of OspA, OspB, and flagellin in protective immunity to Lyme borreliosis in laboratory mice.

OpenAIRE

Fikrig, E; Barthold, S W; Marcantonio, N; Deponte, K; Kantor, F S; Flavell, R A

1992-01-01

Vaccination with recombinant outer surface protein A (OspA) has been shown to protect mice from infection with Borrelia burgdorferi, the Lyme disease agent. To determine whether antibodies to B. burgdorferi proteins other than OspA are involved in protective immunity, antibodies to OspA were removed from protective anti-B. burgdorferi serum; the residual serum was still protective. Absorption of OspA and OspB antibodies from anti-B. burgdorferi serum eliminated the protective effect. Therefor...

Granulocyte-macrophage stimulating factor (GM-CSF increases circulating dendritic cells but does not abrogate suppression of adaptive cellular immunity in patients with metastatic colorectal cancer receiving chemotherapy

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Martinez Micaela

2012-01-01

Full Text Available Abstract Background Advanced cancer and chemotherapy are both associated with immune system suppression. We initiated a clinical trial in patients receiving chemotherapy for metastatic colorectal cancer to determine if administration of GM-CSF in this setting was immunostimulatory. Methods Between June, 2003 and January, 2007, 20 patients were enrolled in a clinical trial (NCT00257322 in which they received 500 ug GM-CSF daily for 4 days starting 24 hours after each chemotherapy cycle. There were no toxicities or adverse events reported. Blood was obtained before chemotherapy/GM-CSF administration and 24 hours following the final dose of GM-CSF and evaluated for circulating dendritic cells and adaptive immune cellular subsets by flow cytometry. Peripheral blood mononuclear cell (PBMC expression of γ-interferon and T-bet transcription factor (Tbx21 by quantitative real-time PCR was performed as a measure of Th1 adaptive cellular immunity. Pre- and post-treatment (i.e., chemotherapy and GM-CSF samples were evaluable for 16 patients, ranging from 1 to 5 cycles (median 3 cycles, 6 biologic sample time points. Dendritic cells were defined as lineage (- and MHC class II high (+. Results 73% of patients had significant increases in circulating dendritic cells of ~3x for the overall group (5.8% to 13.6%, p = 0.02 and ~5x excluding non-responders (3.2% to 14.5%, p Tbx21 levels declined by 75% following each chemotherapy cycle despite administration of GM-CSF (p = 0.02. PBMC γ-interferon expression, however was unchanged. Conclusions This clinical trial confirms the suppressive effects of chemotherapy on Th1 cellular immunity in patients with metastatic colorectal cancer but demonstrates that mid-cycle administration of GM-CSF can significantly increase the proportion of circulating dendritic cells. As the role of dendritic cells in anti-tumor immunity becomes better defined, GM-CSF administration may provide a non-toxic intervention to augment this arm

Improving engraftment and immune reconstitution in umbilical cord blood transplantation

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Robert eDanby

2014-02-01

Full Text Available Umbilical cord blood (UCB is an important source of haematopoietic stem cells (HSC for allogeneic transplantation when HLA-matched sibling and unrelated donors (MUD are unavailable. Although the overall survival rates of UCB transplantation are comparable to the results with MUD, UCB transplants are associated with slow engraftment, delayed immune reconstitution, and increased opportunistic infections. While this may be a consequence of the lower cell dose in UCB grafts, it also reflects the relative immaturity of cellular immunity within cord blood. Furthermore, the limited number of cells and the non-availability of donor lymphocyte infusions (DLI currently prevent the use of post-transplant cellular immunotherapy to boost donor-derived immunity to treat infection, mixed chimerism and disease relapse. Therefore, to further develop UCB transplantation, many strategies to enhance engraftment and immune reconstitution are currently under investigation. This review summarises our current understanding of engraftment and immune recovery following UCB transplantation and why this differs from allogeneic transplants using other sources of HSC. It also provides an comprehensive overview of the promising techniques being used to improve myeloid and lymphoid recovery, including expansion, homing, and delivery of UCB HSC; combined use of UCB with third party donors; isolation and expansion of NK cells, pathogen specific T cells, and regulatory T cells; methods to protect and/or improve thymopoiesis. As many of these strategies are now in clinical trials, it is anticipated that UCB transplantation will continue to advance, further expanding our understanding of UCB biology and HSC transplantation.

The immune system strikes back: cellular immune responses against indoleamine 2,3-dioxygenase

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Sørensen, Rikke Baek; Berge-Hansen, Linda; Junker, Niels

2009-01-01

BACKGROUND: The enzyme indoleamine 2,3-dioxygenase (IDO) exerts an well established immunosuppressive function in cancer. IDO is expressed within the tumor itself as well as in antigen-presenting cells in tumor-draining lymph nodes, where it promotes the establishment of peripheral immune tolerance...... to tumor antigens. In the present study, we tested the notion whether IDO itself may be subject to immune responses. METHODS AND FINDINGS: The presence of naturally occurring IDO-specific CD8 T cells in cancer patients was determined by MHC/peptide stainings as well as ELISPOT. Antigen specific cytotoxic T...... of the major immune suppressive cell populations. CONCLUSION: IDO may serve as an important and widely applicable target for anti-cancer immunotherapeutic strategies. Furthermore, as emerging evidence suggests that IDO constitutes a significant counter-regulatory mechanism induced by pro-inflammatory signals...

Carnauba wax nanoparticles enhance strong systemic and mucosal cellular and humoral immune responses to HIV-gp140 antigen.

Science.gov (United States)

Arias, Mauricio A; Loxley, Andrew; Eatmon, Christy; Van Roey, Griet; Fairhurst, David; Mitchnick, Mark; Dash, Philip; Cole, Tom; Wegmann, Frank; Sattentau, Quentin; Shattock, Robin

2011-02-01

Induction of humoral responses to HIV at mucosal compartments without inflammation is important for vaccine design. We developed charged wax nanoparticles that efficiently adsorb protein antigens and are internalized by DC in the absence of inflammation. HIV-gp140-adsorbed nanoparticles induced stronger in vitro T-cell proliferation responses than antigen alone. Such responses were greatly enhanced when antigen was co-adsorbed with TLR ligands. Immunogenicity studies in mice showed that intradermal vaccination with HIV-gp140 antigen-adsorbed nanoparticles induced high levels of specific IgG. Importantly, intranasal immunization with HIV-gp140-adsorbed nanoparticles greatly enhanced serum and vaginal IgG and IgA responses. Our results show that HIV-gp140-carrying wax nanoparticles can induce strong cellular/humoral immune responses without inflammation and may be of potential use as effective mucosal adjuvants for HIV vaccine candidates. Copyright © 2010 Elsevier Ltd. All rights reserved.

Roles of IFN-γ and γδ T cells in protective immunity against blood-stage malaria

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Shin-Ichi eInoue

2013-08-01

Full Text Available Malaria is caused by infection with Plasmodium parasites. Various studies with knockout mice have indicated that IFN-γ plays essential roles in protective immunity against blood-stage Plasmodium infection. However, after Plasmodium infection, increased IFN-γ production by various types of cells is involved not only in protective immunity, but also in immunopathology. Recent reports have shown that IFN-γ acts as a pro-inflammatory cytokine to induce not only the activation of macrophages, but also the generation of uncommon myelolymphoid progenitor cells after Plasmodium infection. However, the effects of IFN-γ on hematopoietic stem cells and progenitor cells are unclear. Therefore, the regulation of hematopoiesis by IFN-γ during Plasmodium infection remains to be clarified. Although there are conflicting reports concerning the significance of γδ T cells in protective immunity against Plasmodium infection, γδ T cells may respond to infection and produce IFN-γ as innate immune cells in the early phase of blood-stage malaria. Our recent studies have shown that γδ T cells express CD40 ligand and produce IFN-γ after Plasmodium infection, resulting in the enhancement of dendritic cell activation as part of the immune response to eliminate Plasmodium parasites. These data suggest that the function of γδ T cells is similar to that of NK cells. Although several reports suggest that γδ T cells have the potential to act as memory cells for various infections, it remains to be determined whether memory γδ T cells are generated by Plasmodium infection and whether memory γδ T cells can contribute to the host defense against re-infection with Plasmodium. Here, we summarize and discuss the effects of IFN-γ and the various functions of γδ T cells in blood-stage Plasmodium infection.

Adaptive immune responses to booster vaccination against yellow fever virus are much reduced compared to those after primary vaccination

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Kongsgaard, Michael; Bassi, Maria Rosaria; Rasmussen, Michael

2017-01-01

Outbreaks of Yellow Fever occur regularly in endemic areas of Africa and South America frequently leading to mass vaccination campaigns straining the availability of the attenuated Yellow Fever vaccine, YF-17D. The WHO has recently decided to discontinue regular booster-vaccinations since a single...... vaccination is deemed to confer life-long immune protection. Here, we have examined humoral (neutralizing antibody) and cellular (CD8 and CD4 T cell) immune responses in primary and booster vaccinees (the latter spanning 8 to 36 years after primary vaccination). After primary vaccination, we observed strong...... cellular immune responses with T cell activation peaking ≈2 weeks and subsiding to background levels ≈ 4 weeks post-vaccination. The number of antigen-specific CD8+ T cells declined over the following years. In >90% of vaccinees, in vitro expandable T cells could still be detected >10 years post-vaccination...

Evaluation of an economical sunlamp that emits a near solar UV power spectrum for conducting photoimmunological and sunscreen immune protection studies

International Nuclear Information System (INIS)

Beasley, D.G.; Roberts, L.K.; Beard, J.; Stanfield, J.W.

1996-01-01

Unlike FS-type UVB sunlamps, which have a significant amount of effective immunosuppressive non-solar UV energy at wavelengths below 295 nm, the immunosuppression effectiveness spectrum of UVA-340 sunlamps was nearly identical to that of a solar simulator. The purpose of this study was to evaluate this sunlamp for conducting photoimmunological and sunscreen immune protection studies. Groups of C3H mice were exposed to a range of UVA-340 sunlamp doses (0.25 kJ/m 2 to 20.0 kJ/m 2 ) to establish a dose-response curve and determine the minimum immune suppression dose (MISD) for induction of local-type suppression of contact hypersensitivity (CH). The MISD, defined as the lowest UV dose given to produce ∼ 50% suppression of the CH response in mice, was determined to be 1.0 kJ/m 2 for UVA-340 sunlamps. Immune protection tests on four marketed sunscreen lotions (sun protection factors [SPF] 4, 8, 15 and 30) were then conducted with UVA-340 sunlamps using MISD as the endpoint. The immune protection factors for these sunscreens were equivalent to the level of protection predicted by their labeled SPF. These results are similar to those we have previously obtained using a solar simulator. (author)

Immunization

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... a lot worse. Some are even life-threatening. Immunization shots, or vaccinations, are essential. They protect against ... B, polio, tetanus, diphtheria, and pertussis (whooping cough). Immunizations are important for adults as well as children. ...

Identifying the Role of E2 Domains on Alphavirus Neutralization and Protective Immune Responses.

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James Weger-Lucarelli

Full Text Available Chikungunya virus (CHIKV and other alphaviruses are the etiologic agents of numerous diseases in both humans and animals. Despite this, the viral mediators of protective immunity against alphaviruses are poorly understood, highlighted by the lack of a licensed human vaccine for any member of this virus genus. The alphavirus E2, the receptor-binding envelope protein, is considered to be the predominant target of the protective host immune response. Although envelope protein domains have been studied for vaccine and neutralization in flaviviruses, their role in alphaviruses is less characterized. Here, we describe the role of the alphavirus E2 domains in neutralization and protection through the use of chimeric viruses.Four chimeric viruses were constructed in which individual E2 domains of CHIKV were replaced with the corresponding domain from Semliki Forest virus (SFV (ΔDomA/ΔDomB/ΔDomC/ ΔDomA+B. Vaccination studies in mice (both live and inactivated virus revealed that domain B was the primary determinant of neutralization. Neutralization studies with CHIKV immune serum from humans were consistent with mouse studies, as ΔDomB was poorly neutralized.Using chimeric viruses, it was determined that the alphavirus E2 domain B was the critical target of neutralizing antibodies in both mice and humans. Therefore, chimeric viruses may have more relevance for vaccine discovery than peptide-based approaches, which only detect linear epitopes. This study provides new insight into the role of alphavirus E2 domains on neutralization determinants and may be useful for the design of novel therapeutic technologies.

Toxoplasma gondii vs ionizing radiation: cell and humoral immunity in spleen and gut of isogenic mice immunized with 60Co irradiated tachyzoites

International Nuclear Information System (INIS)

Galisteo Junior, Andres Jimenez

2008-01-01

We are developing a vaccine for toxoplasmosis, using ionizing radiation as a tool. Here we analyzed the production of systemic and intestinal immunity, with protection studies, in several strains of inbred mice, by oral or parenteral route, using 255 Gy irradiated tachyzoites of T. gondii RH strain, with challenge with cysts of ME- 49 strain. C57Bl/6j, BALB/c and C57Bl/6j IFN-γ -/- mice were immunized with 10 7 irradiated tachyzoites, be parenteral or oral route. Those preparations, both by parenteral or oral routes, induced the production of specific IgG, mainly of the lgG2b subclass, and IgA immunoglobulins in serum, , as determined by ELISA. IgM production was negligible. Parenteral immunized mice showed higher IgG avidity maturation, as compared to oral immunized mice. Fecal excretion of IgG, IgA and IgM was detected in stools of immunized animals, more intense in oral immunized mice. In cellular immunity studies, induced by antigen, with detection of cytokine production by quantitative real-time PCR, there are a great production of IFN-y by spleen cells, with lower levels in Peyer patches cells, where there are a greater IL-2 production. Challenge studies in immunized mice demonstrated protection to infection in all used schedules, greater in BALB/c mice. C57Bl/6j IFN-γ - /- mice, when immunized, showed no signs of disease and produced similar or greater levels of antibodies than wild type mice. They also excreted S-lgA and S-IgM in stools, but with low numbers of brain cysts in parenteral immunized mice, despite similar mortality. Our data points to a fair possibility of use of those irradiated parasites as an oral vaccine, devised to use for veterinary or wild felines vaccination, reducing the production of oocysts by those hosts and interrupting the chain transmission of human toxoplasmosis. (author)

Effect of radiotherapy on immunity function of cancer patients receiving radiotherapy

International Nuclear Information System (INIS)

Li Xinli; Zhu Shentao; Xu Jiuhong

2003-01-01

Objective: In order to observe the effect of radiotherapy on immunity function of cancer patients receiving radiotherapy. Methods: Cellular immunity is determined by APAAP; Humoral immunity is determined by transmission method. Results: The items of cellular immunity is lower than the control after radiotherapy. These items decrease continually. The difference between before and after radiotherapy has statistic significance. Of all Humoral immunity items, IgA, IgM decreased after radiotherapy and the difference has statistic significance. Conclusions: Radiotherapy can damage patients' immunity function

Enhancing repair of radiation-induced strand breaks in cellular DNA as a radiotherapeutic potential

International Nuclear Information System (INIS)

Nair, C.K.K.

2014-01-01

Protection of mammalian organisms including man from deleterious effects of ionizing radiation is of paramount importance and development of effective approaches to combat radiation damages using non-toxic radioprotectors is of considerable interest for defence, nuclear industries, radiation accidents, space travels, etc., besides the protection of normal tissues during radiotherapy of tumours. Many synthetic as well as natural compounds have been investigated in the recent past for their efficacy to protect the biological systems from radiation induced damages. They include sulfhydryl compounds, antioxidants, plant extracts, immune-modulators, and other agents. However, the inherent toxicity of many of the synthetic agents at the effective radio-protective concentration warranted further search for safer and more effective radio-protectors. In this context, therapeutic radioprotectors which are effective on post irradiation administration are of special relevance. One of the property that can be applied while screening for such radiation protective therapeutics is their ability to enhance repair of radiation-induced lesions in cellular DNA in terms of cellular repair index based on the parameters of the DNA following comet assay. Post irradiation administration of some natural and synthetic agents have shown their potential to enhance repair of radiation-induced strand breaks in cellular DNA in mice. These include phytoceuticals such as gallic acid, sesamol etc., extracts of medicinal plants such as Andrographis panniculata, and a few synthetic compounds such as tocopherol-mono-glucoside. The talk will give an overview of the work on DNA repair enhancement by a few natural and synthetic agents. (author)

Exploratory study on Th1 epitope-induced protective immunity against Coxiella burnetii infection.

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Xiaolu Xiong

Full Text Available Coxiella burnetii is a Gram-negative bacterium that causes Q fever in humans. In the present study, 131 candidate peptides were selected from the major immunodominant proteins (MIPs of C. burnetii due to their high-affinity binding capacity for the MHC class II molecule H2 I-A(b based on bioinformatic analyses. Twenty-two of the candidate peptides with distinct MIP epitopes were well recognized by the IFN-γ recall responses of CD4(+ T cells from mice immunized with parental proteins in an ELISPOT assay. In addition, 7 of the 22 peptides could efficiently induce CD4(+ T cells from mice immunized with C. burnetii to rapidly proliferate and significantly increase IFN-γ production. Significantly higher levels of IL-2, IL-12p70, IFN-γ, and TNF-α were also detected in serum from mice immunized with a pool of the 7 peptides. Immunization with the pool of 7 peptides, but not the individual peptides, conferred a significant protection against C. burnetii infection in mice, suggesting that these Th1 peptides could work together to efficiently activate CD4(+ T cells to produce the Th1-type immune response against C. burnetii infection. These observations could contribute to the rational design of molecular vaccines for Q fever.

Partial Protection of Mice against Trypanosoma cruzi after Immunizing with the TcY 72 Antigenic Preparation

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Yara M Gomes

1999-03-01

Full Text Available A 72 kDa Trypanosoma cruzi glycoprotein recognized by the 164C11 monoclonal antibody (IgM isotype was purified by preparative electrophoresis. The antigenic preparation obtained, named TcY 72, was used to immunize C57Bl/10 mice. The following results were observed after immunization: (1 induction of higher titres of IgG than IgM antibodies, as evaluated by indirect immunofluorescence; (2 significant DTH after injection of epimastigotes in mice footpads; (3 peak parasitemia in immunized mice was significantly reduced and animals were negative by 13 days post-infection, although the mice still succumb to infection; (4 the phenotypic analysis of spleen cell populations showed a decrease in the CD4/CD8 ratio in immunized mice. Taken as a whole, these findings indicate that TcY 72 is immunogenic and potentially important for protective immunity.

Oral or parenteral administration of replication-deficient adenoviruses expressing the measles virus haemagglutinin and fusion proteins: protective immune responses in rodents.

Science.gov (United States)

Fooks, A R; Jeevarajah, D; Lee, J; Warnes, A; Niewiesk, S; ter Meulen, V; Stephenson, J R; Clegg, J C

1998-05-01

The genes encoding the measles virus (MV) haemagglutinin (H) and fusion (F) proteins were placed under the control of the human cytomegalovirus immediate early promoter in a replication-deficient adenovirus vector. Immunofluorescence and radioimmune precipitation demonstrated the synthesis of each protein and biological activity was confirmed by the detection of haemadsorption and fusion activities in infected cells. Oral as well as parenteral administration of the H-expressing recombinant adenovirus elicited a significant protective response in mice challenged with MV. While the F-expressing adenovirus failed to protect mice, cotton rats immunized with either the H- or F-expressing recombinant showed reduced MV replication in the lungs. Antibodies elicited in mice following immunization with either recombinant had no in vitro neutralizing activity, suggesting a protective mechanism involving a cell-mediated immune response. This study demonstrates the feasibility of using oral administration of adenovirus recombinants to induce protective responses to heterologous proteins.

Protective Immunity Induced by DNA Vaccination against Ranavirus Infection in Chinese Giant Salamander Andrias davidianus

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Zhong-Yuan Chen

2018-01-01

Full Text Available Andrias davidianus ranavirus (ADRV is an emerging viral pathogen that causes severe systemic hemorrhagic disease in Chinese giant salamanders. There is an urgent need for developing an effective vaccine against this fatal disease. In this study, DNA vaccines containing the ADRV 2L gene (pcDNA-2L and the 58L gene (pcDNA-58L were respectively constructed, and their immune protective effects were evaluated in Chinese giant salamanders. In vitro and in vivo expression of the vaccine plasmids were confirmed in transfected cells and muscle tissues of vaccinated Chinese giant salamanders by using immunoblot analysis or RT-PCR. Following ADRV challenge, the Chinese giant salamanders vaccinated with pcDNA-2L showed a relative percent survival (RPS of 66.7%, which was significant higher than that in Chinese giant salamanders immunized with pcDNA-58L (RPS of 3.3%. Moreover, the specific antibody against ADRV was detected in Chinese giant salamanders vaccinated with pcDNA-2L at 14 and 21 days post-vaccination by indirect enzyme-linked immunosorbent assay (ELISA. Transcriptional analysis revealed that the expression levels of immune-related genes including type I interferon (IFN, myxovirus resistance (Mx, major histocompatibility complex class IA (MHC IA, and immunoglobulin M (IgM were strongly up-regulated after vaccination with pcDNA-2L. Furthermore, vaccination with pcDNA-2L significantly suppressed the virus replication, which was seen by a low viral load in the spleen of Chinese giant salamander survivals after ADRV challenge. These results indicated that pcDNA-2L could induce a significant innate immune response and an adaptive immune response involving both humoral and cell-mediated immunity that conferred effective protection against ADRV infection, and might be a potential vaccine candidate for controlling ADRV disease in Chinese giant salamanders.

Roles of microRNA in the immature immune system of neonates.

Science.gov (United States)

Yu, Hong-Ren; Huang, Lien-Hung; Li, Sung-Chou

2018-06-13

Neonates have an immature immune system; therefore, their immune activities are different from the activities of adult immune systems. Such differences between neonates and adults are reflected by cell population constitutions, immune responses, cytokine production, and the expression of cellular/humoral molecules, which contribute to the specific neonatal microbial susceptibility and atopic properties. MicroRNAs (miRNAs) have been discovered to modulate many aspects of immune responses. Herein, we summarize the distinct manifestations of the neonatal immune system, including cellular and non-cellular components. We also review the current findings on the modulatory effects of miRNAs on the neonatal immune system. These findings suggest that miRNAs have the potential to be useful therapeutic targets for certain infection or inflammatory conditions by modulating the neonatal immune system. In the future, we need a more comprehensive understanding in regard to miRNAs and how they modulate specific immune cells in neonates. Copyright © 2018. Published by Elsevier B.V.

Humoral and cellular immune responses to modified hepatitis B ...

African Journals Online (AJOL)

Purpose: To evaluate the immunogenicity and types of immune response of a quality-controlled modified recombinant hepatitis B surface antigen (HBsAg) plasmid encoding HBsAg in mice. Methods: The characterized plasmid DNA was used in the immunization of Balb/c mice. Three groups of mice were intramuscularly ...

Recombinant Kunjin virus replicon vaccines induce protective T-cell immunity against human papillomavirus 16 E7-expressing tumour

International Nuclear Information System (INIS)

Herd, Karen A.; Harvey, Tracey; Khromykh, Alexander A.; Tindle, Robert W.

2004-01-01

The persistence of the E7 oncoprotein in transformed cells in human papillomavirus (HPV)-associated cervical cancer provides a tumour-specific antigen to which immunotherapeutic strategies may be directed. Self-replicating RNA (replicon) vaccine vectors derived from the flavivirus Kunjin (KUN) have recently been reported to induce T-cell immunity. Here, we report that inclusion of a CTL epitope of HPV16 E7 protein into a polyepitope encoded by a KUN vector induced E7-directed T-cell responses and protected mice against challenge with an E7-expressing epithelial tumour. We found replicon RNA packaged into virus-like particles to be more effective than naked replicon RNA or plasmid DNA constructed to allow replicon RNA transcription in vivo. Protective immunity was induced although the E7 CTL epitope was subdominant in the context of other CTL epitopes in the polyepitope. The results demonstrate the efficacy of the KUN replicon vector system for inducing protective immunity directed towards a virally encoded human tumour-specific antigen, and for inducing multi-epitopic CTL responses

Pretreatment with Cry1Ac Protoxin Modulates the Immune Response, and Increases the Survival of Plasmodium-Infected CBA/Ca Mice

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Martha Legorreta-Herrera

2010-01-01

Full Text Available Malaria is a major global health problem that kills 1-2 million people each year. Despite exhaustive research, naturally acquired immunity is poorly understood. Cry1A proteins are potent immunogens with adjuvant properties and are able to induce strong cellular and humoral responses. In fact, it has been shown that administration of Cry1Ac protoxin alone or with amoebic lysates induces protection against the lethal infection caused by the protozoa Naegleria fowleri. In this work, we studied whether Cry1Ac is able to activate the innate immune response to induce protection against Plasmodium berghei ANKA (lethal and P. chabaudi AS (nonlethal parasites in CBA/Ca mice. Treatment with Cry1Ac induced protection against both Plasmodium species in terms of reduced parasitaemia, longer survival time, modulation of pro- and anti-inflammatory cytokines, and increased levels of specific antibodies against Plasmodium. Understanding how to boost innate immunity to Plasmodium infection should lead to immunologically based intervention strategies.

Effect of the nanoformulation of siRNA-lipid assemblies on their cellular uptake and immune stimulation

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Kubota, Kohei; Onishi, Kohei; Sawaki, Kazuaki; Li, Tianshu; Mitsuoka, Kaoru; Sato, Takaaki; Takeoka, Shinji

2017-01-01

Two lipid-based nanoformulations have been used to date in clinical studies: lipoplexes and lipid nanoparticles (LNPs). In this study, we prepared small interfering RNA (siRNA)-loaded carriers using lipid components of the same composition to form molecular assemblies of differing structures, and evaluated the impact of structure on cellular uptake and immune stimulation. Lipoplexes are electrostatic complexes formed by mixing preformed cationic lipid liposomes with anionic siRNA in an aqueous environment, whereas LNPs are nanoparticles embedding siRNA prepared by mixing an alcoholic lipid solution with an aqueous siRNA solution in one step. Although the physicochemical properties of lipoplexes and LNPs were similar except for small increases in apparent size of lipoplexes and zeta potential of LNPs, siRNA uptake efficiency of LNPs was significantly higher than that of lipoplexes. Furthermore, in the case of LNPs, both siRNA and lipid were effectively incorporated into cells in a co-assembled state; however, in the case of lipoplexes, the amount of siRNA internalized into cells was small in comparison with lipid. siRNAs in lipoplexes were thought to be more likely to localize on the particle surface and thereby undergo dissociation into the medium. Inflammatory cytokine responses also appeared to differ between lipoplexes and LNPs. For tumor necrosis factor-α, release was mainly caused by siRNA. On the other hand, the release of interleukin-1β was mainly due to the cationic nature of particles. LNPs released lower amounts of tumor necrosis factor-α and interleukin-1β than lipoplexes and were thus considered to be better tolerated with respect to cytokine release. In conclusion, siRNA-loaded nanoformulations effect their cellular uptake and immune stimulation in a manner that depends on the structure of the molecular assembly; therefore, nanoformulations should be optimized before extending studies into the in vivo environment. PMID:28790820

Immune mechanisms in Babesia-infected animals

International Nuclear Information System (INIS)

Phillips, R.S.

1980-01-01

The course of a Babesia infection depends on the species of host and parasite involved. Animals infected with virulent babesias may need chemotherapy before acquired immunity develops. Maintenance of immunity is not dependent on the presence of the parasite. Babesia infections are characteristically of long duration. The immune response to babesias includes both humoral and cellular components. Antibody levels detected in serodiagnostic tests do not relate to levels of resistance to the parasite. Some antibodies, however, appear to be protective. Antiparasitic antibodies may damage parasites in or outside the red cell and act as opsonins. T-cell-deficient and anti-lymphocyte-serum-treated rodents are more susceptible to rodent piroplasms indicating a role for T-cells as either helper cells and/or as mediators of cell-mediated immunity (CMI). There is indirect evidence of CMI, but the cell-mediated mechanisms involved in parasite killing are not known. In domestic animals immunity is largely species- and strain-specific. Antigenic variation by babesias occurs. In rodents, however, there is cross-immunity between different species of rodent piroplasms and between rodent piroplasms and some malaria parasites. Prior infection with agents such as BCG, and Corynebacterium parvum, gives mice non-specific resistance to rodent piroplasms possibly mediated through a soluble non-antibody factor. This factor may also be liberated during piroplasm infections and by being toxic to malaria parasites account for heterologous immunity. Active immunization against babesias has been achieved with avirulent strains, irradiated parasites and dead parasites in adjuvant. During Babesia infections the primary and, to a lesser degree, the secondary immune response to heterologous antigens can be depressed. Maximum depression coincides with peak parasitaemia when antigen priming may be abolished completely. Immunosuppression during Babesia infections can prolong or exacerbate concurrent

A Salmonella typhimurium ghost vaccine induces cytokine expression in vitro and immune responses in vivo and protects rats against homologous and heterologous challenges.

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Nagarajan Vinod

Full Text Available Salmonella enteritidis and Salmonella typhimurium are important food-borne bacterial pathogens, which are responsible for diarrhea and gastroenteritis in humans and animals. In this study, S. typhimurium bacterial ghost (STG was generated based on minimum inhibitory concentration (MIC of sodium hydroxide (NaOH. Experimental studies performed using in vitro and in vivo experimental model systems to characterize effects of STG as a vaccine candidate. When compared with murine macrophages (RAW 264.7 exposed to PBS buffer (98.1%, the macrophages exposed to formalin-killed inactivated cells (FKC, live wild-type bacterial cells and NaOH-induced STG at 1 × 108 CFU/mL showed 85.6%, 66.5% and 84.6% cell viability, respectively. It suggests that STG significantly reduces the cytotoxic effect of wild-type bacterial cells. Furthermore, STG is an excellent inducer for mRNAs of pro-inflammatory cytokine (TNF-α, IL-1β and factor (iNOS, anti-inflammatory cytokine (IL-10 and dual activities (IL-6 in the stimulated macrophage cells. In vivo, STG vaccine induced humoral and cellular immune responses and protection against homologous and heterologous challenges in rats. Furthermore, the immunogenicity and protective efficacy of STG vaccine were compared with those of FKC and non-vaccinated PBS control groups. The vaccinated rats from STG group exhibited higher levels of serum IgG antibody responses, serum bactericidal antibodies, and CD4+ and CD8+ T-cell populations than those of the FKC and PBS control groups. Most importantly, after challenge with homologous and heterologous strains, the bacterial loads in the STG group were markedly lower than the FKC and PBS control groups. In conclusion, these findings suggest that the STG vaccine induces protective immunity against homologous and heterologous challenges.

Cellular immune therapy for chronic lymphocytic leukemia

NARCIS (Netherlands)

Kater, Arnon P.; van Oers, Marinus H. J.; Kipps, Thomas J.

2007-01-01

Although chemotherapy can induce complete responses in patients with chronic lymphocytic leukemia (CLL), it is not considered curative. Treated patients generally develop recurrent disease requiring additional therapy, which can cause worsening immune dysfunction, myelosuppression, and selection for

Incorporation of a recombinant Eimeria maxima IMP1 antigen into nanoparticles confers protective immunity against E. Maxima challenge infection.

Science.gov (United States)

Jenkins, Mark C; Stevens, Laura; O'Brien, Celia; Parker, Carolyn; Miska, Katrzyna; Konjufca, Vjollca

2018-02-14

The purpose of this study was to determine if conjugating a recombinant Eimeria maxima protein, namely EmaxIMP1, into 20 nm polystyrene nanoparticles (NP) could improve the level of protective immunity against E. maxima challenge infection. Recombinant EmaxIMP1 was expressed in Escherichia coli as a poly-His fusion protein, purified by NiNTA chromatography, and conjugated to 20 nm polystyrene NP (NP-EmaxIMP1). NP-EMaxIMP1 or control non-recombinant (NP-NR) protein were delivered per os to newly-hatched broiler chicks with subsequent booster immunizations at 3 and 21 days of age. In battery cage studies (n = 4), chickens immunized with NP-EMaxIMP1 displayed complete protection as measured by weight gain (WG) against E. maxima challenge compared to chickens immunized with NP-NR. WG in the NP-EMaxIMP1-immunized groups was identical to WG in chickens that were not infected with E. maxima infected chickens. In floor pen studies (n = 2), chickens immunized with NP-EMaxIMP1 displayed partial protection as measured by WG against E. maxima challenge compared to chickens immunized with NP-NR. In order to understand the basis for immune stimulation, newly-hatched chicks were inoculated per os with NP-EMaxIMP1 or NP-NR protein, and the small intestine, bursa, and spleen, were examined for NP localization at 1 h and 6 h post-inoculation. Within 1 h, both NP-EMaxIMP1 and NP-NR were observed in all 3 tissues. An increase was observed in the level of NP-EmaxIMP1 and NP-NR in all tissues at 6 h post-inoculation. These data indicate that 20 nm NP-EmaxIMP1 or NP-NR reached deeper tissues within hours of oral inoculation and elicited complete to partial immunity against E. maxima challenge infection. Published by Elsevier Ltd.

CAF01 potentiates immune responses and efficacy of an inactivated influenza vaccine in ferrets.

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Cyril Jean-Marie Martel

Full Text Available Trivalent inactivated vaccines (TIV against influenza are given to 350 million people every year. Most of these are non-adjuvanted vaccines whose immunogenicity and protective efficacy are considered suboptimal. Commercially available non-adjuvanted TIV are known to elicit mainly a humoral immune response, whereas the induction of cell-mediated immune responses is negligible. Recently, a cationic liposomal adjuvant (dimethyldioctadecylammonium/trehalose 6,6'-dibehenate, CAF01 was developed. CAF01 has proven to enhance both humoral and cell-mediated immune responses to a number of different experimental vaccine candidates. In this study, we compared the immune responses in ferrets to a commercially available TIV with the responses to the same vaccine mixed with the CAF01 adjuvant. Two recently circulating H1N1 viruses were used as challenge to test the vaccine efficacy. CAF01 improved the immunogenicity of the vaccine, with increased influenza-specific IgA and IgG levels. Additionally, CAF01 promoted cellular-mediated immunity as indicated by interferon-gamma expressing lymphocytes, measured by flow cytometry. CAF01 also enhanced the protection conferred by the vaccine by reducing the viral load measured in nasal washes by RT-PCR. Finally, CAF01 allowed for dose-reduction and led to higher levels of protection compared to TIV adjuvanted with a squalene emulsion. The data obtained in this human-relevant challenge model supports the potential of CAF01 in future influenza vaccines.

Immunomodulator-based enhancement of anti smallpox immune responses.

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Osmarie Martínez

Full Text Available The current live vaccinia virus vaccine used in the prevention of smallpox is contraindicated for millions of immune-compromised individuals. Although vaccination with the current smallpox vaccine produces protective immunity, it might result in mild to serious health complications for some vaccinees. Thus, there is a critical need for the production of a safe virus-free vaccine against smallpox that is available to everyone. For that reason, we investigated the impact of imiquimod and resiquimod (Toll-like receptors agonists, and the codon-usage optimization of the vaccinia virus A27L gene in the enhancement of the immune response, with intent of producing a safe, virus-free DNA vaccine coding for the A27 vaccinia virus protein.We analyzed the cellular-immune response by measuring the IFN-γ production of splenocytes by ELISPOT, the humoral-immune responses measuring total IgG and IgG2a/IgG1 ratios by ELISA, and the TH1 and TH2 cytokine profiles by ELISA, in mice immunized with our vaccine formulation.The proposed vaccine formulation enhanced the A27L vaccine-mediated production of IFN-γ on mouse spleens, and increased the humoral immunity with a TH1-biased response. Also, our vaccine induced a TH1 cytokine milieu, which is important against viral infections.These results support the efforts to find a new mechanism to enhance an immune response against smallpox, through the implementation of a safe, virus-free DNA vaccination platform.

Immunomodulator-based enhancement of anti smallpox immune responses.

Science.gov (United States)

Martínez, Osmarie; Miranda, Eric; Ramírez, Maite; Santos, Saritza; Rivera, Carlos; Vázquez, Luis; Sánchez, Tomás; Tremblay, Raymond L; Ríos-Olivares, Eddy; Otero, Miguel

2015-01-01

The current live vaccinia virus vaccine used in the prevention of smallpox is contraindicated for millions of immune-compromised individuals. Although vaccination with the current smallpox vaccine produces protective immunity, it might result in mild to serious health complications for some vaccinees. Thus, there is a critical need for the production of a safe virus-free vaccine against smallpox that is available to everyone. For that reason, we investigated the impact of imiquimod and resiquimod (Toll-like receptors agonists), and the codon-usage optimization of the vaccinia virus A27L gene in the enhancement of the immune response, with intent of producing a safe, virus-free DNA vaccine coding for the A27 vaccinia virus protein. We analyzed the cellular-immune response by measuring the IFN-γ production of splenocytes by ELISPOT, the humoral-immune responses measuring total IgG and IgG2a/IgG1 ratios by ELISA, and the TH1 and TH2 cytokine profiles by ELISA, in mice immunized with our vaccine formulation. The proposed vaccine formulation enhanced the A27L vaccine-mediated production of IFN-γ on mouse spleens, and increased the humoral immunity with a TH1-biased response. Also, our vaccine induced a TH1 cytokine milieu, which is important against viral infections. These results support the efforts to find a new mechanism to enhance an immune response against smallpox, through the implementation of a safe, virus-free DNA vaccination platform.

Development of Protective Immunity in New Zealand White Rabbits Challenged with Bacillus anthracis Spores and Treated with Antibiotics and Obiltoxaximab, a Monoclonal Antibody against Protective Antigen.

Science.gov (United States)

Henning, Lisa N; Carpenter, Sarah; Stark, Gregory V; Serbina, Natalya V

2018-02-01

The recommended management of inhalational anthrax, a high-priority bioterrorist threat, includes antibiotics and antitoxins. Obiltoxaximab, a chimeric monoclonal antibody against anthrax protective antigen (PA), is licensed under the U.S. Food and Drug Administration's (FDA's) Animal Rule for the treatment of inhalational anthrax. Because of spore latency, disease reemergence after treatment cessation is a concern, and there is a need to understand the development of endogenous protective immune responses following antitoxin-containing anthrax treatment regimens. Here, acquired protective immunity was examined in New Zealand White (NZW) rabbits challenged with a targeted lethal dose of Bacillus anthracis spores and treated with antibiotics, obiltoxaximab, or a combination of both. Survivors of the primary challenge were rechallenged 9 months later and monitored for survival. Survival rates after primary and rechallenge for controls and animals treated with obiltoxaximab, levofloxacin, or a combination of both were 0, 65, 100, and 95%, and 0, 100, 95, and 89%, respectively. All surviving immune animals had circulating antibodies to PA and serum toxin-neutralizing titers prior to rechallenge. Following rechallenge, systemic bacteremia and toxemia were not detected in most animals, and the levels of circulating anti-PA IgG titers increased starting at 5 days postrechallenge. We conclude that treatment with obiltoxaximab, alone or combined with antibiotics, significantly improves the survival of rabbits that received a lethal inhalation B. anthracis spore challenge dose and does not interfere with the development of immunity. Survivors of primary challenge are protected against reexposure, have rare incidents of systemic bacteremia and toxemia, and have evidence of an anamnestic response. Copyright © 2018 Henning et al.

Development of vaccines against Plasmodium falciparum malaria: taking lessons from naturally acquired protective immunity

DEFF Research Database (Denmark)

Hviid, Lars

2007-01-01

The acquisition of substantial anti-malarial protection in people naturally exposed to P. falciparum is often cited as evidence that malaria vaccines can be developed, but is rarely used to guide the development. We are pursuing the development of vaccines based on antigens and immune responses...

Dynamic Nature of Noncoding RNA Regulation of Adaptive Immune Response

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Franca Citarella

2013-08-01

Full Text Available Immune response plays a fundamental role in protecting the organism from infections; however, dysregulation often occurs and can be detrimental for the organism, leading to a variety of immune-mediated diseases. Recently our understanding of the molecular and cellular networks regulating the immune response, and, in particular, adaptive immunity, has improved dramatically. For many years, much of the focus has been on the study of protein regulators; nevertheless, recent evidence points to a fundamental role for specific classes of noncoding RNAs (ncRNAs in regulating development, activation and homeostasis of the immune system. Although microRNAs (miRNAs are the most comprehensive and well-studied, a number of reports suggest the exciting possibility that long ncRNAs (lncRNAs could mediate host response and immune function. Finally, evidence is also accumulating that suggests a role for miRNAs and other small ncRNAs in autocrine, paracrine and exocrine signaling events, thus highlighting an elaborate network of regulatory interactions mediated by different classes of ncRNAs during immune response. This review will explore the multifaceted roles of ncRNAs in the adaptive immune response. In particular, we will focus on the well-established role of miRNAs and on the emerging role of lncRNAs and circulating ncRNAs, which all make indispensable contributions to the understanding of the multilayered modulation of the adaptive immune response.

A booster vaccine expressing a latency-associated antigen augments BCG induced immunity and confers enhanced protection against tuberculosis.

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Bappaditya Dey

Full Text Available BACKGROUND: In spite of a consistent protection against tuberculosis (TB in children, Mycobacterium bovis Bacille Calmette-Guerin (BCG fails to provide adequate protection against the disease in adults as well as against reactivation of latent infections or exogenous reinfections. It has been speculated that failure to generate adequate memory T cell response, elicitation of inadequate immune response against latency-associated antigens and inability to impart long-term immunity against M. tuberculosis infections are some of the key factors responsible for the limited efficiency of BCG in controlling TB. METHODS/PRINCIPAL FINDINGS: In this study, we evaluated the ability of a DNA vaccine expressing α-crystallin--a key latency antigen of M. tuberculosis to boost the BCG induced immunity. 'BCG prime-DNA boost' regimen (B/D confers robust protection in guinea pigs along with a reduced pathology in comparison to BCG vaccination (1.37 log(10 and 1.96 log(10 fewer bacilli in lungs and spleen, respectively; p<0.01. In addition, B/D regimen also confers enhanced protection in mice. Further, we show that B/D immunization in mice results in a heightened frequency of PPD and antigen specific multi-functional CD4 T cells (3(+ simultaneously producing interferon (IFNγ, tumor necrosis factor (TNFα and interleukin (IL2. CONCLUSIONS/SIGNIFICANCE: These results clearly indicate the superiority of α-crystallin based B/D regimen over BCG. Our study, also demonstrates that protection against TB is predictable by an increased frequency of 3(+ Th1 cells with superior effector functions. We anticipate that this study would significantly contribute towards the development of superior booster vaccines for BCG vaccinated individuals. In addition, this regimen can also be expected to reduce the risk of developing active TB due to reactivation of latent infection.

A prophylactic multivalent vaccine against different filovirus species is immunogenic and provides protection from lethal infections with Ebolavirus and Marburgvirus species in non-human primates.

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Benoit Callendret

Full Text Available The search for a universal filovirus vaccine that provides protection against multiple filovirus species has been prompted by sporadic but highly lethal outbreaks of Ebolavirus and Marburgvirus infections. A good prophylactic vaccine should be able to provide protection to all known filovirus species and as an upside potentially protect from newly emerging virus strains. We investigated the immunogenicity and protection elicited by multivalent vaccines expressing glycoproteins (GP from Ebola virus (EBOV, Sudan virus (SUDV, Taï Forest virus (TAFV and Marburg virus (MARV. Immune responses against filovirus GP have been associated with protection from disease. The GP antigens were expressed by adenovirus serotypes 26 and 35 (Ad26 and Ad35 and modified Vaccinia virus Ankara (MVA vectors, all selected for their strong immunogenicity and good safety profile. Using fully lethal NHP intramuscular challenge models, we assessed different vaccination regimens for immunogenicity and protection from filovirus disease. Heterologous multivalent Ad26-Ad35 prime-boost vaccination regimens could give full protection against MARV (range 75%-100% protection and EBOV (range 50% to 100% challenge, and partial protection (75% against SUDV challenge. Heterologous multivalent Ad26-MVA prime-boost immunization gave full protection against EBOV challenge in a small cohort study. The use of such multivalent vaccines did not show overt immune interference in comparison with monovalent vaccines. Multivalent vaccines induced GP-specific antibody responses and cellular IFNγ responses to each GP expressed by the vaccine, and cross-reactivity to TAFV GP was detected in a trivalent vaccine expressing GP from EBOV, SUDV and MARV. In the EBOV challenge studies, higher humoral EBOV GP-specific immune responses (p = 0.0004 were associated with survival from EBOV challenge and less so for cellular immune responses (p = 0.0320. These results demonstrate that it is feasible to

A prophylactic multivalent vaccine against different filovirus species is immunogenic and provides protection from lethal infections with Ebolavirus and Marburgvirus species in non-human primates.

Science.gov (United States)

Callendret, Benoit; Vellinga, Jort; Wunderlich, Kerstin; Rodriguez, Ariane; Steigerwald, Robin; Dirmeier, Ulrike; Cheminay, Cedric; Volkmann, Ariane; Brasel, Trevor; Carrion, Ricardo; Giavedoni, Luis D; Patterson, Jean L; Mire, Chad E; Geisbert, Thomas W; Hooper, Jay W; Weijtens, Mo; Hartkoorn-Pasma, Jutta; Custers, Jerome; Grazia Pau, Maria; Schuitemaker, Hanneke; Zahn, Roland

2018-01-01

The search for a universal filovirus vaccine that provides protection against multiple filovirus species has been prompted by sporadic but highly lethal outbreaks of Ebolavirus and Marburgvirus infections. A good prophylactic vaccine should be able to provide protection to all known filovirus species and as an upside potentially protect from newly emerging virus strains. We investigated the immunogenicity and protection elicited by multivalent vaccines expressing glycoproteins (GP) from Ebola virus (EBOV), Sudan virus (SUDV), Taï Forest virus (TAFV) and Marburg virus (MARV). Immune responses against filovirus GP have been associated with protection from disease. The GP antigens were expressed by adenovirus serotypes 26 and 35 (Ad26 and Ad35) and modified Vaccinia virus Ankara (MVA) vectors, all selected for their strong immunogenicity and good safety profile. Using fully lethal NHP intramuscular challenge models, we assessed different vaccination regimens for immunogenicity and protection from filovirus disease. Heterologous multivalent Ad26-Ad35 prime-boost vaccination regimens could give full protection against MARV (range 75%-100% protection) and EBOV (range 50% to 100%) challenge, and partial protection (75%) against SUDV challenge. Heterologous multivalent Ad26-MVA prime-boost immunization gave full protection against EBOV challenge in a small cohort study. The use of such multivalent vaccines did not show overt immune interference in comparison with monovalent vaccines. Multivalent vaccines induced GP-specific antibody responses and cellular IFNγ responses to each GP expressed by the vaccine, and cross-reactivity to TAFV GP was detected in a trivalent vaccine expressing GP from EBOV, SUDV and MARV. In the EBOV challenge studies, higher humoral EBOV GP-specific immune responses (p = 0.0004) were associated with survival from EBOV challenge and less so for cellular immune responses (p = 0.0320). These results demonstrate that it is feasible to generate a

Protective effect of yeast β-glucan on immune system of mice irradiated by carbon ions

International Nuclear Information System (INIS)

Wang Ying; Lu Dong; Wei Wei; Jing Xigang; Wang Jufang; Li Wenjian

2012-01-01

Abstract. To detect Yeast β-glucan's protective effect on mice's immune system after C ion beam radiation, mice were used as the test model. We observed the weight, hair color and behavior of mice everyday within a 7 d period of time after irradiation. Meanwhile, the content of white blood cell, on the 2nd and 7th day after irradiation was detected. We detected the thymus and spleen SOD, GSH-PX activity and MDA content of the mice on the 8th day. The results showed that yeast β-glucan could reduce the rapid weight loss of mice, increase white blood cell content, increase thymus and spleen SOD, GSH-PX activity, decrease MDA content of thymus and spleen. These results indicate that yeast 13-glucan can protect mice's immune system against C ion beam radiation damage. (authors)

Competitive inhibitor of cellular alpha-glucosidases protects mice from lethal dengue virus infection

OpenAIRE

Chang, Jinhong; Schul, Wouter; Yip, Andy; Xu, Xiaodong; Guo, Ju-Tao; Block, Timothy M.

2011-01-01

Dengue virus infection causes diseases in people, ranging from the acute febrile illness Dengue fever, to life-threatening Dengue Hemorrhagic Fever/Dengue Shock Syndrome. We previously reported that a host cellular α-glucosidases I and II inhibitor, imino sugar CM-10-18, potently inhibited dengue virus replication in cultured cells, and significantly reduced viremia in dengue virus infected AG129 mice. In this report we show that CM-10-18 also significantly protects mice from death and/or dis...

Salmonella adhesion, invasion and cellular immune responses are differentially affected by iron concentrations in a combined in vitro gut fermentation-cell model.

Science.gov (United States)

Dostal, Alexandra; Gagnon, Mélanie; Chassard, Christophe; Zimmermann, Michael Bruce; O'Mahony, Liam; Lacroix, Christophe

2014-01-01

In regions with a high infectious disease burden, concerns have been raised about the safety of iron supplementation because higher iron concentrations in the gut lumen may increase risk of enteropathogen infection. The aim of this study was to investigate interactions of the enteropathogen Salmonella enterica ssp. enterica Typhimurium with intestinal cells under different iron concentrations encountered in the gut lumen during iron deficiency and supplementation using an in vitro colonic fermentation system inoculated with immobilized child gut microbiota combined with Caco-2/HT29-MTX co-culture monolayers. Colonic fermentation effluents obtained during normal, low (chelation by 2,2'-dipyridyl) and high iron (26.5 mg iron/L) fermentation conditions containing Salmonella or pure Salmonella cultures with similar iron conditions were applied to cellular monolayers. Salmonella adhesion and invasion capacity, cellular integrity and immune response were assessed. Under high iron conditions in pure culture, Salmonella adhesion was 8-fold increased compared to normal iron conditions while invasion was not affected leading to decreased invasion efficiency (-86%). Moreover, cellular cytokines IL-1β, IL-6, IL-8 and TNF-α secretion as well as NF-κB activation in THP-1 cells were attenuated under high iron conditions. Low iron conditions in pure culture increased Salmonella invasion correlating with an increase in IL-8 release. In fermentation effluents, Salmonella adhesion was 12-fold and invasion was 428-fold reduced compared to pure culture. Salmonella in high iron fermentation effluents had decreased invasion efficiency (-77.1%) and cellular TNF-α release compared to normal iron effluent. The presence of commensal microbiota and bacterial metabolites in fermentation effluents reduced adhesion and invasion of Salmonella compared to pure culture highlighting the importance of the gut microbiota as a barrier during pathogen invasion. High iron concentrations as

Neutrophil degranulation and immunosuppression in patients with GBM: restoration of cellular immune function by targeting arginase I.

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Sippel, Trisha R; White, Jason; Nag, Kamalika; Tsvankin, Vadim; Klaassen, Marci; Kleinschmidt-DeMasters, B K; Waziri, Allen

2011-11-15

The source of glioblastoma (GBM)-associated immunosuppression remains multifactorial. We sought to clarify and therapeutically target myeloid cell-derived peripheral immunosuppression in patients with GBM. Direct ex vivo T-cell function, serum Arginase I (ArgI) levels, and circulating myeloid lineage populations were compared between patients with GBM and normal donors or patients with other intracranial tumors. Immunofunctional assays were conducted using bulk and sorted cell populations to explore the potential transfer of myeloid cell-mediated immunosuppression and to identify a potential mechanism for these effects. ArgI-mediated immunosuppression was therapeutically targeted in vitro through pharmacologic inhibition or arginine supplementation. We identified a significantly expanded population of circulating, degranulated neutrophils associated with elevated levels of serum ArgI and decreased T-cell CD3ζ expression within peripheral blood from patients with GBM. Sorted CD11b(+) cells from patients with GBM were found to markedly suppress normal donor T-cell function in coculture, and media harvested from mitogen-stimulated GBM peripheral blood mononuclear cell (PBMC) or GBM-associated mixed lymphoid reactions showed ArgI levels that were significantly higher than controls. Critically, T-cell suppression in both settings could be completely reversed through pharmacologic ArgI inhibition or with arginine supplementation. These data indicate that peripheral cellular immunosuppression in patients with GBM is associated with neutrophil degranulation and elevated levels of circulating ArgI, and that T-cell function can be restored in these individuals by targeting ArgI. These data identify a novel pathway of GBM-mediated suppression of cellular immunity and offer a potential therapeutic window for improving antitumor immunity in affected patients.

Shigella IpaB and IpaD displayed on L. lactis bacterium-like particles induce protective immunity in adult and infant mice.

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Heine, Shannon J; Franco-Mahecha, Olga L; Chen, Xiaotong; Choudhari, Shyamal; Blackwelder, William C; van Roosmalen, Maarten L; Leenhouts, Kees; Picking, Wendy L; Pasetti, Marcela F

2015-08-01

Shigella spp. are among the enteric pathogens with the highest attributable incidence of moderate-to-severe diarrhea in children under 5 years of age living in endemic areas. There are no vaccines available to prevent this disease. In this work, we investigated a new Shigella vaccine concept consisting of nonliving, self-adjuvanted, Lactococcus lactis bacterium-like particles (BLP) displaying Shigella invasion plasmid antigen (Ipa) B and IpaD and examined its immunogenicity and protective efficacy in adult and newborn/infant mice immunized via the nasal route. Unique advantages of this approach include the potential for broad protection due to the highly conserved structure of the Ipas and the safety and practicality of a probiotic-based mucosal/adjuvant delivery platform. Immunization of adult mice with BLP-IpaB and BLP-IpaD (BLP-IpaB/D) induced high levels of Ipa-specific serum IgG and stool IgA in a dose-dependent manner. Immune responses and protection were enhanced by BLP delivery. Vaccine-induced serum antibodies exhibited opsonophagocytic and cytotoxic neutralizing activity, and IpaB/D IgG titers correlated with increased survival post-challenge. Ipa-specific antibody secreting cells were detected in nasal tissue and lungs, as well as IgG in bronchoalveolar lavage. Bone marrow cells produced IpaB/D-specific antibodies and contributed to protection after adoptive transfer. The BLP-IpaB/D vaccine conferred 90% and 80% protection against S. flexneri and S. sonnei, respectively. Mice immunized with BLP-IpaB/D as newborns also developed IpaB and IpaD serum antibodies; 90% were protected against S. flexneri and 44% against S. sonnei. The BLP-IpaB/D vaccine is a promising candidate for safe, practical and potentially effective immunization of children against shigellosis.

Gamma irradiated antigen extracts improves the immune response and protection in experimental toxoplasmosis

Energy Technology Data Exchange (ETDEWEB)

Costa, Andrea da; Galisteo Junior, Andres Jimenez; Andrade Junior, Heitor Franco de, E-mail: andreacosta@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Medicina Tropical; Zorgi, Nahiara Estevez [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Ciencias Biomedicas; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

We aimed to use ionizing radiation on soluble extracts of T. gondii tachyzoites (AgTg) and tested the ability of these extracts to induce immunity in BALB/c mice against a challenge. T. gondii RH strain AgTg was irradiated with Co-60 at 0.25 to 4 kGy and were affected after 1 kGy, as evidenced by a progressive high molecular weight protein aggregates and no loss in antigenicity, as detected by immunoblotting, except after 4kGy. BALB/c mice were immunized with biweekly doses of 03 s.c. native or irradiated AgTg without adjuvants; the anti-T.gondii IgG production was detected by ELISA, and higher levels and avidity were detected in mice immunized with 1.5 kGy AgTg compared to controls (p<0.05). Mice immunized with native AgTg exhibited spleen CD19{sup +} B, CD3{sup +}CD4{sup +} or CD3{sup +}CD8{sup +} T cell proliferation levels of 5%, while 1.5 kGy-immunized mice exhibited spleen cell proliferation levels of 12.2%, primarily for CD19{sup +} or CD3{sup +}CD8{sup +} lymphocytes and less evidently for CD3{sup +}CD4{sup +} (8.8%) helper T lymphocytes. All cells from control mice showed little to no proliferation when stimulated with AgTg. These cells secreted more IFN-γ in the 1.5 kGy AgTg-immunized group (p<0.05). BALB/c mice immunized with 1.5 kGy and challenged with different strains of T. gondii were partially protected, as evidenced by survival after RH virulent strain challenge (p<0.0001) but also after ME-49 strain challenge: the brain cyst numbers (p<0.05) and the levels of T. gondii DNA measured by real-time PCR (p<0.05) decreased compared to non-immunized controls. (author)

Gamma irradiated antigen extracts improves the immune response and protection in experimental toxoplasmosis

International Nuclear Information System (INIS)

Costa, Andrea da; Galisteo Junior, Andres Jimenez; Andrade Junior, Heitor Franco de

2015-01-01

We aimed to use ionizing radiation on soluble extracts of T. gondii tachyzoites (AgTg) and tested the ability of these extracts to induce immunity in BALB/c mice against a challenge. T. gondii RH strain AgTg was irradiated with Co-60 at 0.25 to 4 kGy and were affected after 1 kGy, as evidenced by a progressive high molecular weight protein aggregates and no loss in antigenicity, as detected by immunoblotting, except after 4kGy. BALB/c mice were immunized with biweekly doses of 03 s.c. native or irradiated AgTg without adjuvants; the anti-T.gondii IgG production was detected by ELISA, and higher levels and avidity were detected in mice immunized with 1.5 kGy AgTg compared to controls (p<0.05). Mice immunized with native AgTg exhibited spleen CD19 + B, CD3 + CD4 + or CD3 + CD8 + T cell proliferation levels of 5%, while 1.5 kGy-immunized mice exhibited spleen cell proliferation levels of 12.2%, primarily for CD19 + or CD3 + CD8 + lymphocytes and less evidently for CD3 + CD4 + (8.8%) helper T lymphocytes. All cells from control mice showed little to no proliferation when stimulated with AgTg. These cells secreted more IFN-γ in the 1.5 kGy AgTg-immunized group (p<0.05). BALB/c mice immunized with 1.5 kGy and challenged with different strains of T. gondii were partially protected, as evidenced by survival after RH virulent strain challenge (p<0.0001) but also after ME-49 strain challenge: the brain cyst numbers (p<0.05) and the levels of T. gondii DNA measured by real-time PCR (p<0.05) decreased compared to non-immunized controls. (author)

The role of intestinal microbiota and the immune system.

Science.gov (United States)

Purchiaroni, F; Tortora, A; Gabrielli, M; Bertucci, F; Gigante, G; Ianiro, G; Ojetti, V; Scarpellini, E; Gasbarrini, A

2013-02-01

The human gut is an ecosystem consisting of a great number of commensal bacteria living in symbiosis with the host. Several data confirm that gut microbiota is engaged in a dynamic interaction with the intestinal innate and adaptive immune system, affecting different aspects of its development and function. To review the immunological functions of gut microbiota and improve knowledge of its therapeutic implications for several intestinal and extra-intestinal diseases associated to dysregulation of the immune system. Significant articles were identified by literature search and selected based on content, including atopic diseases, inflammatory bowel diseases and treatment of these conditions with probiotics. Accumulating evidence indicates that intestinal microflora has protective, metabolic, trophic and immunological functions and is able to establish a "cross-talk" with the immune component of mucosal immunity, comprising cellular and soluble elements. When one or more steps in this fine interaction fail, autoimmune or auto-inflammatory diseases may occur. Furthermore, it results from the data that probiotics, used for the treatment of the diseases caused by the dysregulation of the immune system, can have a beneficial effect by different mechanisms. Gut microbiota interacts with both innate and adaptive immune system, playing a pivotal role in maintenance and disruption of gut immune quiescence. A cross talk between the mucosal immune system and endogenous microflora favours a mutual growth, survival and inflammatory control of the intestinal ecosystem. Based on these evidences, probiotics can be used as an ecological therapy in the treatment of immune diseases.  

[Human milk, immune responses and health effects].

Science.gov (United States)

Løland, Beate Fossum; Baerug, Anne B; Nylander, Gro

2007-09-20

Besides providing optimal nutrition to infants, human milk contains a multitude of immunological components. These components are important for protection against infections and also support the development and maturation of the infant's own immune system. This review focuses on the function of some classical immunocomponents of human milk. Relevant studies are presented that describe health benefits of human milk for the child and of lactation for the mother. Relevant articles were found mainly by searching PubMed. Humoral and cellular components of human milk confer protection against infections in the respiratory--, gastrointestinal--and urinary tract. Human milk also protects premature children from neonatal sepsis and necrotizing enterocolitis. There is evidence that human milk may confer long-term benefits such as lower risk of certain autoimmune diseases, inflammatory bowel disease and probably some malignancies. Human milk possibly affects components of the metabolic syndrome. Recent studies demonstrate long-term health benefits of lactation also for the mother. A reduced incidence of breast cancer is best documented. An increasing number of studies indicate protection against ovarian cancer, rheumatoid arthritis and type II diabetes.

Particular Characterisation of an In-Vitro-DTH Test to Monitor Cellular Immunity - Applications for Patient Care and Space Flight

Science.gov (United States)

Feurecker, M.; Mayer, W.; Gruber, M.; Muckenthaler, F.; Draenert, R.; Bogner, J.; Kaufmann, I.; Crucian, B.; Rykova, M.; Morukov, B.;

Immunization of Mice with Anthrax Protective Antigen Limits Cardiotoxicity but Not Hepatotoxicity Following Lethal Toxin Challenge

Directory of Open Access Journals (Sweden)

T. Scott Devera

2015-06-01

Full Text Available Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI, and hepatic alanine aminotransferase (ALT, and aspartate aminotransferase (AST, it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities.

Host immunity in the protective response to vaccination with heat-killed Burkholderia mallei

Directory of Open Access Journals (Sweden)

Paessler Slobodan

2008-09-01

Full Text Available Abstract Background We performed initial cell, cytokine and complement depletion studies to investigate the possible role of these effectors in response to vaccination with heat-killed Burkholderia mallei in a susceptible BALB/c mouse model of infection. Results While protection with heat-killed bacilli did not result in sterilizing immunity, limited protection was afforded against an otherwise lethal infection and provided insight into potential host protective mechanisms. Our results demonstrated that mice depleted of either B cells, TNF-α or IFN-γ exhibited decreased survival rates, indicating a role for these effectors in obtaining partial protection from a lethal challenge by the intraperitoneal route. Additionally, complement depletion had no effect on immunoglobulin production when compared to non-complement depleted controls infected intranasally. Conclusion The data provide a basis for future studies of protection via vaccination using either subunit or whole-organism vaccine preparations from lethal infection in the experimental BALB/c mouse model. The results of this study demonstrate participation of B220+ cells and pro-inflammatory cytokines IFN-γ and TNF-α in protection following HK vaccination.